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Find video protocols related to scientific articles indexed in Pubmed.
A review of neuraminidase inhibitor susceptibility in influenza strains.
Expert Rev Anti Infect Ther
PUBLISHED: 10-11-2014
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Influenza human infections are considered as a persistent global public health issue. Whereas vaccination is important for prevention, given its limitations, antiviral therapy is at the forefront of treatment, while it also plays a significant role in prevention. Currently, two classes of drugs, adamantanes (M2 blockers) and neuraminidase inhibitors (NAIs), are available for treatment and chemoprophylaxis of influenza infections. Given the resistance patterns of circulating influenza strains, adamantanes are not currently recommended. The current review mainly focuses on the development of resistance to NAIs among A and B subtypes of influenza virus strains over the last 5 years. 'Permissive' drift mutations and reassortment of viral gene segments have resulted in NAI oseltamivir-resistant A/(H1N1) variants that rapidly became predominant worldwide in the period 2007-2009. However, the prevalence of antiviral resistance to NAI zanamivir remains relatively low. In addition, the recently developed NAIs, peramivir and laninamivir, while licensed in certain countries, are still under evaluation and only a few reports have described resistance to peramivir. Although in 2014, the majority of circulating human influenza viruses remains susceptible to all NAIs, the emergence of oseltamivir-resistant influenza variants that could retain viral transmissibility, highlights the necessity for enhanced epidemiological and microbiological surveillance and clinical assessment of antiviral resistance.
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Administration of a Triple versus a Standard Double Antimicrobial Regimen for Human Brucellosis More Efficiently Eliminates Bacterial DNA Load.
Antimicrob. Agents Chemother.
PUBLISHED: 09-22-2014
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The effects of doxycycline-streptomycin-rifampin versus a standard doxycycline-streptomycin regimen on residual Brucella DNA were compared in 36 acute brucellosis patients. At admission, all patients given triple (n = 22) and double (n = 14) regimens had detectable Brucella DNA with similar mean loads (P = 0.982). At follow-up, 14 to 20 months postpresentation, significantly more patients receiving triple than double regimens had undetectable Brucella DNA (P = 0.026). The doxycycline-streptomycin-rifampin regimen eliminates Brucella DNA more efficiently than doxycycline-streptomycin, which may result in superior long-term clearance of Brucella.
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Virological and serological analysis of a recent Middle East respiratory syndrome coronavirus infection case on a triple combination antiviral regimen.
Int. J. Antimicrob. Agents
PUBLISHED: 07-25-2014
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Serological, molecular and phylogenetic analyses of a recently imported case of Middle East respiratory syndrome coronavirus (MERS-CoV) in Greece are reported. Although MERS-CoV remained detectable in the respiratory tract secretions of the patient until the fourth week of illness, viraemia was last detected 2 days after initiation of triple combination therapy with pegylated interferon, ribavirin and lopinavir/ritonavir, administered from Day 13 of illness. Phylogenetic analysis of the virus showed close similarity with other human MERS-CoVs from the recent Jeddah outbreak in Saudi Arabia. Immunoglobulin G (IgG) titres peaked 3 weeks after the onset of illness, whilst IgM levels remained constantly elevated during the follow-up period (second to fifth week of illness). Serological testing confirmed by virus neutralisation assay detected an additional case that was a close contact of the patient.
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Linezolid-dependent function and structure adaptation of ribosomes in a Staphylococcus epidermidis strain exhibiting linezolid dependence.
Antimicrob. Agents Chemother.
PUBLISHED: 06-02-2014
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Linezolid-dependent growth was recently reported in Staphylococcus epidermidis clinical strains carrying mutations associated with linezolid resistance. To investigate this unexpected behavior at the molecular level, we isolated active ribosomes from one of the linezolid-dependent strains and we compared them with ribosomes isolated from a wild-type strain. Both strains were grown in the absence and presence of linezolid. Detailed biochemical and structural analyses revealed essential differences in the function and structure of isolated ribosomes which were assembled in the presence of linezolid. The catalytic activity of peptidyltransferase was found to be significantly higher in the ribosomes derived from the linezolid-dependent strain. Interestingly, the same ribosomes exhibited an abnormal ribosomal subunit dissociation profile on a sucrose gradient in the absence of linezolid, but the profile was restored after treatment of the ribosomes with an excess of the antibiotic. Our study suggests that linezolid most likely modified the ribosomal assembly procedure, leading to a new functional ribosomal population active only in the presence of linezolid. Therefore, the higher growth rate of the partially linezolid-dependent strains could be attributed to the functional and structural adaptations of ribosomes to linezolid.
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The Balkan region: NDM-1-producing Klebsiella pneumoniae ST11 clonal strain causing outbreaks in Greece.
J. Antimicrob. Chemother.
PUBLISHED: 04-15-2014
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Despite the fact that the NDM-1 carbapenemase has successfully disseminated worldwide, outbreaks remain uncommon in the European region. We describe the characteristics of the first outbreaks caused by NDM-1-producing Klebsiella pneumoniae clonal isolates in Greece.
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Modified CLSI extended-spectrum ?-lactamase (ESBL) confirmatory test for phenotypic detection of ESBLs among Enterobacteriaceae producing various ?-lactamases.
J. Clin. Microbiol.
PUBLISHED: 02-26-2014
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The worldwide dissemination of Enterobacteriaceae producing AmpC ?-lactamases and carbapenemases makes difficult the phenotypic detection of extended-spectrum ?-lactamases (ESBLs), as they may be masked by these additional enzymes. A modification of the CLSI ESBL confirmatory test was developed and evaluated in a comparative study for its ability to successfully detect ESBLs among Enterobacteriaceae producing various carbapenemases (Klebsiella pneumoniae carbapenemase [KPC], VIM, NDM, and OXA-48) and plasmidic or derepressed AmpCs. The modified CLSI ESBL confirmatory test was performed with cefotaxime and ceftazidime disks with and without clavulanate, on which both boronic acid (BA) and EDTA were dispensed. A total of 162 genotypically confirmed ESBL-positive Enterobacteriaceae isolates (83 carbapenemase/ESBL producers, 25 AmpC/ESBL producers, and 54 ESBL-only producers) were examined. For comparison, 139 genotypically confirmed ESBL-negative Enterobacteriaceae isolates (94 of them possessed carbapenemases and 20 possessed AmpCs) were also tested. The standard CLSI ESBL confirmatory test was positive for 106 of the 162 ESBL producers (sensitivity, 65.4%) and showed false-positive results for 4 of the 139 non-ESBL producers (specificity, 97.1%). The modified CLSI ESBL confirmatory test detected 158 of 162 ESBL producers (sensitivity, 97.5%) and showed no false-positive results for non-ESBL producers (specificity, 100%). The findings of the study demonstrate that the modified CLSI ESBL confirmatory test using antibiotic disks containing both BA and EDTA accurately detects ESBLs in Enterobacteriaceae regardless of the coexistence of additional ?-lactam resistance mechanisms.
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The immune response after stimulation with wall components of gram-positive bacteria and fungi.
Immunol. Lett.
PUBLISHED: 01-15-2014
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Although several components of the microbial wall of gram-positive bacteria and fungi possess immunostimulatory properties, their pathogenetic role remains incompletely evaluated. The purpose of this study was to assess the basic immune status of patients susceptible to infections and their capability for cytokine production after stimulation with wall components of gram-positive bacteria and fungi. We measured serum cytokine levels as well as cytokine production after ex vivo lipoteichoic acid (LTA) and mannan stimulation of whole blood. The blood was taken from 10 healthy volunteers, 10 patients with end-stage renal disease (ESRD), 10 patients with diabetes mellitus (DM), and 10 patients on their 2nd day of stay in the Intensive Care Unit (ICU), who suffered from non septic systemic inflammatory response syndrome (SIRS) and had an APACHE II score ?25. We used 1 ?g/ml LTA and 100 ?g/ml mannan for an incubation period of 8 h to stimulate 100 ?l aliquots of whole blood. All patient groups had higher baseline values of TNF-?, IL-6, IL-1?, and IL-10 compared to the control group, but only for ICU patients the difference was statistically significant. The ratio IL-10/IL-6 was found 0.33, 0.22, and 0.96 in healthy persons, ESRD, and DM patients respectively, and 1.32 in ICU patients. In all examined groups, the levels of cytokines significantly increased after stimulation by LTA and mannan, although in severely ill patients this change was considerably smaller, possibly reflecting a state of monocytes' depression and relative hyporesponsiveness. No significant differences between the LTA and the mannan stimulation were observed.
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Synthetic peptides for efficient discrimination of anti-enterovirus antibodies at the serotype level.
Peptides
PUBLISHED: 01-04-2014
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Enteroviruses are important human pathogens, causing a broad spectrum of diseases from minor common colds to fatal myocarditis. However, certain disease syndromes are caused by one or few serotypes. Serotype identification is difficult due to the laborious neutralization tests that lack of sensitivity, while in commercial ELISAs homotypic antibodies' activities are largely masked by the recognition of genera-specific epitopes by heterotypic antibodies. In the present study homotypic assays were developed with the ability to discriminate different enterovirus serotypes. Seventy-three children sera, positive for IgM antibodies against enterovirus genus and 49 healthy children were examined for the presence of antibodies against 14 synthetic peptides derived from a non-conserved region of the VP1 protein of coxsackieviruses B2, B3, B4, B5, A9, A16, A24, echoviruses 6, 7, 9, 11, 30, enterovirus 71 and parechovirus 1. 50% of the anti-enterovirus IgM positive sera (>150 BU) reacted with the peptides with the majority of them to preferentially recognize one of them, supporting the homotypic nature of our assay. Inhibition studies yielded homologous inhibition rates 67-95% suggesting that specific peptide recognition actually occurred. The diagnostic value of our assay was tested in blood samples drawn over a 1.5-year period from a 5-year old patient. The anti-enterovirus reactivity was clearly attributed to echovirus serotype 11. The IgM/IgG antibody ratio was reversed 4 months later and subsequently IgM antibodies dropped below the cutoff point. In this paper we demonstrate that our assay can be used to discriminate between antibodies targeting different enterovirus serotypes.
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Laboratory and Clinical Characteristics of Human West Nile Virus Infections during 2011 Outbreak in Southern Greece.
Vector Borne Zoonotic Dis.
PUBLISHED: 12-20-2013
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Abstract During the summer-autumn of 2011, a human outbreak of West Nile virus (WNV) infection occurred in southern Greece, following the first outbreak during 2010 in northern Greece. An investigation was performed to analyze laboratory diagnosis, geographic distribution, and clinical features of WNV cases in southern Greece. Serum and cerebrospinal fluid (CSF) specimens from all patients seeking laboratory diagnosis for suspected WNV infection were tested for the presence of specific WNV immunoglobulin M (IgM) and IgG antibodies. Detection of WNV RNA in CSF and whole blood samples was accomplished by real-time PCR. During August-October of 2011, 31 confirmed or probable cases of WNV infection were identified. In 25 of them, individuals experienced severe neurological manifestations and were classified as WNV neuroinvasive disease cases. Risk factors such as advanced age, hypertension, and diabetes mellitus were identified in most cases with neurological complications. As many as 25 of the WNV cases occurred in the broader region of Athens; the majority of them (17 cases) were identified in municipalities of Eastern Attica, located almost 40?km from the metropolitan area of Athens and 500?km from Central Macedonia, where the 2010 WNV outbreak occurred. The spread of the virus in a newly affected area of the country suggests that WNV has been established in Greece and disease transmission will be continued in the future.
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Growth Retardation, Reduced Invasiveness and Impaired Colistin-Mediated Cell Death Associated with Colistin Resistance Development in Acinetobacter baumannii.
Antimicrob. Agents Chemother.
PUBLISHED: 11-18-2013
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Two colistin-susceptible/colistin-resistant (ColS/ColR) pairs of Acinetobacter baumannii strains assigned to the worldwide prevalent international clone 2 were sequentially recovered from two patients after prolonged colistin administration. Compared with the respective ColS isolates (Ab248 and Ab299, both having colistin MIC 0.5 ?g/ml), both ColR isolates (Ab249 and Ab347, colistin MICs 128 and 32 ?g/ml, respectively) overexpressed significantly pmrCAB genes, had single aminoacid shifts in PmrB protein and exhibited significantly slower growth. The ColR isolate Ab347, tested by proteomic analysis in comparison with its ColS counterpart Ab299, underexpressed the proteins CsuA/B and C from the csu operon (necessary for biofilm formation). This isolate also underexpressed aconitase B and different enzymes involved in the oxidative stress response (KatE catalase, superoxide dismutase, alkyl hydroperoxide reductase), suggesting reduced response to reactive oxygen species (ROS) and, consequently, impaired colistin-mediated cell death through hydroxyl radical production. ColS isolates that were indistinguishable by macrorestriction analysis to Ab299 caused six sequential bloodstream infections and isolates indistinguishable to Ab248 severe soft tissue infection, while ColR isolates indistinguishable to Ab347 and Ab249 were mainly colonizers. In particular, a ColS isolate identical to Ab299 was still invading the bloodstream 90 days after the colonization of this patient by ColR isolates. These observations indicate considerably lower invasiveness of A. baumannii clinical isolates following the development of colistin resistance.
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West Nile Virus State of the Art Report of MALWEST Project.
Andriani Marka, Alexandros Diamantidis, Anna Papa, George Valiakos, Serafeim C Chaintoutis, Dimitrios Doukas, Persefoni Tserkezou, Alexios Giannakopoulos, Konstantinos Papaspyropoulos, Eleni Patsoula, Evangelos Badieritakis, Agoritsa Baka, Maria Tseroni, Danai Pervanidou, Nikos T Papadopoulos, George Koliopoulos, Dimitrios Tontis, Chrysostomos I Dovas, Charalambos Billinis, Athanassios Tsakris, Jenny Kremastinou, Christos Hadjichristodoulou, , Nikolaos Vakalis, Evdokia Vassalou, Spyridoula Zarzani, Athanassios Zounos, Katerina Komata, Georgios Balatsos, Stavroula Beleri, Anastasia Mpimpa, Vasilios Papavasilopoulos, Ioannis Rodis, Grigorios Spanakos, Nikolaos Tegos, Vasiliki Spyrou, Zisis Dalabiras, Periklis Birtsas, Labrini Athanasiou, Maria Papanastassopoulou, Charalambos Ioannou, Christos Athanasiou, Christos Gerofotis, Elpida Papadopoulou, Theodolinta Testa, Ourania Tsakalidou, George Rachiotis, Nikolaos Bitsolas, Zissis Mamouris, Katerina Moutou, Theologia Sarafidou, Konstantinos Stamatis, Konstantina Sarri, Sotirios Tsiodras, Theano Georgakopoulou, Marios Detsis, Maria Mavrouli, Anastasia Stavropoulou, Lida Politi, Georgia Mageira, Varvara Christopoulou, Georgia Diamantopoulou, Nikolaos Spanakis, Georgia Vrioni, Evangelia-Theofano Piperaki, Kornilia Mitsopoulou, Ilias Kioulos, Antonios Michaelakis, Ioannis Stathis, Ioannis Tselentis, Anna Psaroulaki, Maria Keramarou, Dimosthenis Chochlakis, Yeorgios Photis, Maria Konstantinou, Panagiotis Manetos, Stylianos Tsobanoglou, Spyros Mourelatos, Vasilis Antalis, Panagiotis Pergantas, Georgios Eleftheriou.
Int J Environ Res Public Health
PUBLISHED: 07-30-2013
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During the last three years Greece is experiencing the emergence of West Nile virus (WNV) epidemics. Within this framework, an integrated surveillance and control programme (MALWEST project) with thirteen associate partners was launched aiming to investigate the disease and suggest appropriate interventions. One out of seven work packages of the project is dedicated to the State of the Art report for WNV. Three expert working groups on humans, animals and mosquitoes were established. Medical databases (PubMed, Scopus) were searched together with websites: e.g., WHO, CDC, ECDC. In total, 1,092 relevant articles were initially identified and 258 of them were finally included as references regarding the current knowledge about WNV, along with 36 additional sources (conference papers, reports, book chapters). The review is divided in three sections according to the fields of interest: (1) WNV in humans (epidemiology, molecular characteristics, transmission, diagnosis, treatment, prevention, surveillance); (2) WNV in animals (epidemiological and transmission characteristics concerning birds, horses, reptiles and other animal species) and (3) WNV in mosquitoes (control, surveillance). Finally, some examples of integrated surveillance programmes are presented. The introduction and establishment of the disease in Greece and other European countries further emphasizes the need for thorough research and broadening of our knowledge on this viral pathogen.
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Amphotericin B- and voriconazole-echinocandin combinations against Aspergillus spp.: Effect of serum on inhibitory and fungicidal interactions.
Antimicrob. Agents Chemother.
PUBLISHED: 07-15-2013
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Antifungal combination therapy with voriconazole or amphotericin B and an echinocandin is often employed as primary or salvage therapy for management particularly of refractory aspergillosis. The pharmacodynamic interactions of amphotericin B- and voriconazole-based combinations with the three echinocandins caspofungin, micafungin, and anidulafungin in the presence of serum were tested against 15 Aspergillus fumigatus complex, A. flavus complex, and A. terreus complex isolates to assess both their growth-inhibitory and fungicidal activities. The in vitro activity of each drug alone and in combination at a 1:1 fixed concentration ratio was tested with a broth microdilution colorimetric method, and interactions were assessed by isobolographic analysis. Synergy was found for all amphotericin B- and voriconazole-based combinations, with amphotericin B-based combinations showing strong inhibitory synergistic interactions (interaction indices of 0.20 to 0.52) and with voriconazole-based combinations demonstrating strong fungicidal synergistic interactions (interaction indices of 0.10 to 0.29) (P < 0.001). Drug- and species-specific differences were found, with caspofungin and the A. fumigatus complex exhibiting the weakest synergistic interactions. In the presence of serum, the synergistic interactions were reduced in the order (from largest to smallest decrease) micafungin > anidulafungin > caspofungin, and A. flavus complex > A. fumigatus complex > A. terreus complex, resulting in additive interactions, particularly for inhibitory activities of amphotericin B-echinocandin combinations and fungicidal activities of voriconazole-echinocandin combinations. Drug- and species-specific differences were found in the presence of serum for inhibitory activities of antifungal drugs, with the lowest interaction indices being observed for amphotericin B-caspofungin (median, 0.77) and for the A. terreus complex (median, 0.56). The present in vitro data showed that serum had a major impact on synergistic interactions of amphotericin B-echinocandin and voriconazole-echinocandin combinations, resulting in additive interactions and explaining the indifferent outcomes usually observed in vivo.
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Outbreak caused by an ertapenem-resistant, CTX-M-15-producing Klebsiella pneumoniae sequence type 101 clone carrying an OmpK36 porin variant.
J. Clin. Microbiol.
PUBLISHED: 07-12-2013
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Although numerous studies have documented outbreaks of carbapenem-resistant Klebsiella pneumoniae (CRKP) possessing various carbapenemases, reports on outbreaks due to CRKP possessing extended-spectrum ?-lactamases (ESBLs) and/or AmpCs with porin lesions have been limited. Here, we describe an outbreak caused by an ertapenem-resistant, CTX-M-15-producing clonal K. pneumoniae strain expressing an OmpK36 porin variant. From May 2012 to November 2012, 37 ertapenem-resistant K. pneumoniae isolates phenotypically negative for carbapenemase production were recovered from 19 patients hospitalized in the intensive care unit of a Greek hospital. The isolates were either susceptible or intermediate to other carbapenems and resistant to all remaining ?-lactams but cefotetan. Phenotypic and molecular analysis revealed the presence in all isolates of the blaCTX-M-15 gene on a conjugative 100-kb plasmid, disruption in the expression of the ompK35 gene, and the production of an Ompk36 porin variant. The index case was a patient admitted from another hospital. Active surveillance upon admission and on a weekly basis was immediately initiated; environmental samples were also periodically tested. Molecular typing showed that all clinical isolates as well as two ertapenem-resistant environmental K. pneumoniae isolates belonged to the same clonal type and were assigned to multilocus sequence typing (MLST) sequence type 101 (ST101). As all colonized/infected patients were hospitalized during overlapping periods, cross-infection was considered the main route for the dissemination of the outbreak strain. Despite reinforcement of infection control measures and active surveillance, the outbreak lasted approximately 7 months. Identification of hidden carriers upon admission and by screening on a weekly basis was found valuable for early recognition and subsequent successful management of the outbreak.
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A combined disk test for direct differentiation of carbapenemase-producing enterobacteriaceae in surveillance rectal swabs.
J. Clin. Microbiol.
PUBLISHED: 07-10-2013
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Carbapenemase-producing Enterobacteriaceae (CPE) are rapidly spreading worldwide. Early detection of fecal CPE carriers is essential for effective infection control. Here, we evaluated the performance of a meropenem combined disk test (CDT) for rapidly differentiating CPE isolates directly from rectal swabs. The screening method was applied for 189 rectal swabs from hospitalized patients at high risk for CPE carriage. Swabs were suspended in 1 ml saline and cultured for confluent growth onto a MacConkey agar plate with a meropenem (MER) disk alone, a MER disk plus phenyl boronic acid (PBA), a MER disk plus EDTA, and a MER disk plus PBA and EDTA. An inhibition zone of ? 25 mm around the MER disk alone indicated carriage of carbapenem-resistant organisms. Furthermore, ? 5-mm differences in the inhibition zone between MER disks without and with the inhibitors (PBA, EDTA, or both) were considered positive results for detecting Klebsiella pneumoniae carbapenemase (KPC), metallo-?-lactamase (MBL), or both carbapenemases, respectively. For comparison, rectal suspensions were tested using MacConkey plates with ertapenem (MacERT) disks and PCR (PCR-S) for carbapenemase genes. Of the 189 samples, 97 were genotypically confirmed as CPE positive by one of the three protocols tested. The CDT, MacERT disks, and PCR-S assays exhibited sensitivities of 94.8%, 96.9%, and 94.8% and specificities of 100%, 98.9%, and 100%, respectively, for detecting CPE-positive swabs. Moreover, the CDT correctly differentiated the production of KPC, MBL, or both carbapenemases in 78 of the 97 (80.4%) CPE-positive rectal swabs. Our results demonstrate that the CDT may provide a simple and inexpensive method for detecting and differentiating the carbapenemase type within a single day without requiring further testing and additional delay, supporting the timely implementation of infection control measures.
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Carbapenemase-producing Enterobacteriaceae: now that the storm is finally here, how will timely detection help us fight back?
Future Microbiol
PUBLISHED: 06-08-2013
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Acquired carbapenemases of the Ambler Classes A, B and D have gradually disseminated over the past decade among isolates of the Enterobacteriaceae family. Located on highly mobile genetic elements, these enzymes have established their presence in successful bacterial clones, signaling the prelude to a novel endemic era in the hospital setting. In such a context, prompt detection of carbapenemase-producing microorganisms seems warranted, not only for the selection of an appropriate antibiotic regimen, but also for organizing and implementing effective surveillance and infection control measures. However, issues regarding detection, confirmatory testing and characterization persist. Determination of carbapenemase production via susceptibility pattern interpretation may not always be feasible, confirmatory testing remains debatable and precise characterization is a challenge for the clinical laboratory. We aim to review the current situation from a laboratory point of view, highlighting the tools that have been proposed in an effort to help outline reliable screening and detection procedures, with inhibitor-based phenotypic testing as the cornerstone of these strategies, and discuss the necessity for implementing identification of possible producers in the everyday workflow.
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Linezolid dependence in Staphylococcus epidermidis bloodstream isolates.
Emerging Infect. Dis.
PUBLISHED: 06-05-2013
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We document linezolid dependence among 5 highly linezolid-resistant (LRSE) Staphylococcus epidermidis bloodstream isolates that grew substantially faster at 32 µg/mL linezolid presence. These isolates carried the mutations T2504A and C2534T in multiple 23S rRNA copies and 2 mutations leading to relevant amino acid substitutions in L3 protein. Linezolid dependence could account for increasing LRSE emergence.
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Successful short-term cryopreservation of volume-reduced cord blood units in a cryogenic mechanical freezer: effects on cell recovery, viability, and clonogenic potential.
Transfusion
PUBLISHED: 03-28-2013
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BACKGROUND: Cord blood (CB) units are stored from weeks to years in liquid- or vapor-phase nitrogen until they are used for transplantation. We examined the effects of cryostorage in a mechanical freezer at -150°C on critical quality control variables of CB collections to investigate the possible use of mechanical freezers at -150°C as an alternative to storage in liquid- (or vapor-) phase nitrogen. STUDY DESIGN AND METHODS: A total of 105 CB units were thawed and washed at different time intervals (6, 12, 24, and 36 months). For every thawed CB unit, samples were removed and cell enumeration (total nucleated cells [TNCs], mononuclear cells [MNCs], CD34+, CD133+) was performed. In addition, viability was obtained with the use of flow cytometry, and recoveries were calculated. Also, total absolute colony-forming unit counts were performed and progenitor cell recoveries were studied by clonogenic assays. RESULTS: Significant differences (p?
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The history of the Greek Anti-Malaria League and the influence of the Italian School of Malariology.
Infez Med
PUBLISHED: 03-26-2013
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In 1905, a group of eminent Greek physicians led by Professor of Hygiene and Microbiology Constantinos Savvas and the pediatrician Dr. Ioannis Kardamatis founded the Greek Anti-Malaria League. The League assumed a role that the State would not, and for the next 25 years organized the countrys anti-malaria campaign. During its first steps, the Greek Anti-Malaria League adopted the principles of Professor Angelo Cellis Italian Anti-Malaria League. The Leagues accomplishments include a decrease in malarial prevalence, due to mass treatment with quinine, new legislation ensuring the provision of quinine, State monopoly and the collection of epidemiologic data. However, defeat in the Greek-Turkish War (1922) and the massive influx of one million Greek refugees that ensued, led to a change in malarial epidemiology. In 1928, following a visit to Italy, the Greek League adopted the organization and knowledge of the Italian Malaria Schools in Rome and in Nettuno, and this experience served as the basis of their proposal to the State for the development of the anti-malaria services infrastructure. The State adopted many of Professor Savvas proposals and modified his plan according to Greek needs. The Leagues experience, accumulated during its 25 years of struggle against malaria, was its legacy to the campaigns that eventually accomplished the eradication of malaria from Greece after World War II.
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Comparative evaluation of conventional and real-time PCR assays for detecting Bacteroides fragilis in clinical samples.
J. Clin. Microbiol.
PUBLISHED: 02-27-2013
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A conventional PCR and a real-time PCR for detecting Bacteroides fragilis were evaluated against clinical specimens. Analytical sensitivities were 100 and 40 fg of DNA, respectively. Detection limits were 100 and 10 CFU/ml, respectively. A total of six culture-negative specimens were positive by PCR. Altering the gold standard from "positive culture" to "positive culture or both PCR assays positive" resulted in sensitivities of 91.7% and 100%, respectively, and in specificities of 100% and 98.6%, respectively.
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Clinical evaluation of the endothelial tie-2 crossmatch in ABO compatible and ABO incompatible renal transplants.
Hum. Immunol.
PUBLISHED: 02-20-2013
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The necessity of detection of other than the classical major histocompatibility complex (MHC) and MHC class I-related chain A (MICA) directed antibodies prior to organ transplantation has already been repeatedly reported. A commercial flow cytometric endothelial crossmatch (CM) using isolated peripheral blood tie-2 positive cells provides a tool to detect non-MHC antibodies in addition to antibodies directed to MHC class I and II. The vast majority of circulating tie-2 positive cells expresses HLA-DR but not the A, B blood group antigens. Tie-2 cells are circulating surrogate endothelial cells. In this retrospective study we evaluated the endothelial CM in 51 renal transplantations, 30 with ABO compatible grafts and 21 with ABO incompatible grafts. Fifteen of the ABO compatible recipients (group A) developed unexplained rejection episodes (RE) while the remaining 15 had no RE (group B). Five cases of group A and none of group B had a positive tie-2 CM before transplantation (p=0.042). A positive tie-2 CM was also correlated with graft failure in ABO compatible transplants (p=0.02). No significant correlation was found between a positive pre-transplant tie-2 CM and RE in the ABO incompatible group. This study strongly suggest that a positive tie-2 CM may predict post-transplantation complications in ABO compatible grafts while negative reactions are not predictive. The test is not significantly correlated with RE in ABO incompatible grafts possibly due to applied desensitization.
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Inflammatory bowel disease exacerbation associated with Epstein-Barr virus infection.
Dis. Colon Rectum
PUBLISHED: 02-09-2013
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Epstein-Barr virus infection is associated with inflammatory bowel disease, but its role as a pathogenetic or exacerbating factor remains unclear.
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Susceptibility patterns to extended-spectrum cephalosporins among Enterobacteriaceae harbouring extended-spectrum ?-lactamases using the updated Clinical and Laboratory Standards Institute interpretive criteria.
Int. J. Antimicrob. Agents
PUBLISHED: 02-01-2013
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We examined the effect of applying the updated 2010 Clinical and Laboratory Standards Institute (CLSI) susceptibility breakpoints for extended-spectrum cephalosporins (ESCs) to detect extended-spectrum ?-lactamase (ESBL)-producing Enterobacteriaceae. In total, 202 ESBL-producing, plasmidic AmpC- and carbapenemase-negative isolates derived from separate patients were collected from three Greek hospitals during 2007-2011, including 150 Escherichia coli, 43 Klebsiella pneumoniae and 9 Enterobacter cloacae clinical isolates. ESBLs were detected using the ESBL CLSI confirmatory test and PCR assays. Sequencing analysis showed that 91 (45.0%) of the ESBL-producers carried the bla(CTX-M-3) gene, 66 (32.7%) carried the bla(CTX-M-15) gene and the remaining 45 (22.3%) carried the bla(SHV-5) gene. Minimum inhibitory concentrations for cefotaxime, ceftazidime and cefepime were determined by the agar dilution method. Based on the new CLSI breakpoints, 13 (6.4%) of the ESBL-producers were susceptible to cefotaxime, 90 (44.6%) to ceftazidime and 112 (55.4%) to cefepime; as many as 145 (71.8%) were susceptible to at least one ESC. Among the 150 E. coli, 12 (8.0%), 87 (58.0%) and 79 (52.7%) were susceptible to cefotaxime, ceftazidime and cefepime, respectively, whilst among the 43 K. pneumoniae, 1 (2.3%), 3 (7.0%) and 25 (58.1%) were susceptible to the above ESCs, respectively. None of the nine E. cloacae were susceptible to cefotaxime and ceftazidime, but all except one were susceptible to cefepime. By implementation of the new 2010 CLSI breakpoints, a considerable proportion of ESBL-possessing Enterobacteriaceae would be reported as susceptible, mostly to ceftazidime and cefepime, leading to possible infection control and therapeutic implications.
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Risk factors for carbapenem-resistant Gram-negative bacteremia in intensive care unit patients.
Intensive Care Med
PUBLISHED: 01-22-2013
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Carbapenem-resistant (CR) Gram-negative pathogens have increased substantially. This study was performed to identify the risk factors for development of CR Gram-negative bacteremia (GNB) in intensive care unit (ICU) patients.
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Detection of a phylogenetically distinct IMP-type metallo-?-lactamase, IMP-35, in a CC235 Pseudomonas aeruginosa from the Dutch-German border region (Euregio).
J. Antimicrob. Chemother.
PUBLISHED: 01-22-2013
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To characterize a highly divergent IMP-type metallo-?-lactamase (MBL) variant detected in a multidrug-resistant Pseudomonas aeruginosa clinical isolate.
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Granulomatous infection of the hand and wrist due to Azospirillum spp.
Diagn. Microbiol. Infect. Dis.
PUBLISHED: 01-18-2013
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We report a case of Azospirillum infection manifestating as granulomatous tenosynovitis of the right hand, in an immunocompetent middle-aged female. We highlight the unusual source of the infection, the diagnostic workup, as well as the treatment approach.
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Two cases of severe sepsis caused by Bacillus pumilus in neonatal infants.
J. Med. Microbiol.
PUBLISHED: 12-15-2011
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Bacillus pumilus is an environmental contaminant that has been rarely associated with clinical infections. Here, two cases of severe sepsis caused by B. pumilus are described in two full-term neonates; one in a female infant with no factors predisposing her to infection and the other in a male infant requiring mechanical ventilation and an intravenous catheter. In both cases, the micro-organism was recovered from repeated blood cultures and was identified using biochemical assays and 16S rRNA gene sequencing. Both infants were successfully treated with vancomycin. This report reveals the potential role of B. pumilus as a bloodstream pathogen during infancy.
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Detection of Pseudomonas aeruginosa isolates of the international clonal complex 11 carrying the blaPER-1 extended-spectrum ?-lactamase gene in Greece.
J. Antimicrob. Chemother.
PUBLISHED: 11-08-2011
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The extended-spectrum ?-lactamase (ESBL) PER-1 initially disseminated among Pseudomonas aeruginosa strains in Turkey. Despite reports from other European countries, such strains have not been detected in Greece until now. We describe the first bla(PER-1)-positive P. aeruginosa isolates from Greece and their genetic environment.
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Epidemic waves of the Black Death in the Byzantine Empire (1347-1453 AD).
Infez Med
PUBLISHED: 11-01-2011
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The lack of valid demographic data and the literary ambiguities of the Byzantine chroniclers raise questions about the actual size and mortality rate of the Black Death in the Byzantine Empire. This study presents for the first time a quantitative overview of the Black Death in Byzantium for the period 1347-1453. Our data were obtained from descriptions of the plague, by prominent Byzantine historians and scholars, grouped by time of appearance and geographical spread. During the period 1347-1453, a total of 61 plague reports were noted, which can be distinguished in nine major epidemic waves, 11 local outbreaks and 16 disease-free periods. The capital Constantinople and the Venetian colonies of the Ionian and Aegean Sea were the areas most affected by the plague. The epidemic waves of the Black Death in Byzantium had a total average duration of 3.2 years. Scientific ignorance of the nature of the disease, a turbulent period of warfare and an organized maritime network seem to have contributed to the spread of the disease. Employing quantitative analysis, our multidisciplinary study sheds light from various standpoints on the evolution and dynamic of the plague in the South-eastern Mediterranean during the 14th and 15th centuries, despite the lack of sound morbidity and mortality data.
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Evolution of multidrug-resistant Acinetobacter baumannii clonal lineages: a 10 year study in Greece (2000-09).
J. Antimicrob. Chemother.
PUBLISHED: 09-19-2011
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To analyse the evolution and genetic relatedness of Acinetobacter baumannii clonal lineages in Greece during a 10 year period.
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Containment of an outbreak of KPC-3-producing Klebsiella pneumoniae in Italy.
J. Clin. Microbiol.
PUBLISHED: 09-07-2011
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From March 2009 to May 2009, 24 carbapenem-resistant Klebsiella pneumoniae isolates were recovered from 16 patients hospitalized in an Italian intensive care unit (ICU). All isolates contained KPC-3 carbapenemase and belonged to a single pulsed-field gel electrophoresis (PFGE) clone of multilocus sequence type 258 (designated as ST258). A multimodal infection control program was put into effect, and the spread of the KPC-3-producing K. pneumoniae clone was ultimately controlled without closing the ICU to new admissions. Reinforced infection control measures and strict monitoring of the staff adherence were necessary for the control of the outbreak.
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The challenges of antimicrobial drug resistance in Greece.
Clin. Infect. Dis.
PUBLISHED: 06-22-2011
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Antimicrobial drug resistance rates in Greece are among the highest in Europe. The prevalence of carbapenem-resistant Gram-negative species has increased considerably, including endemic strains in intensive care units. Pandrug-resistant Klebsiella pneumoniae, Acinetobacter baumannii, and Pseudomonas aeruginosa are sporadically reported. Methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus rates are also high in Greek hospitals. Multidrug resistance increases risk of mortality, hospitalization duration and costs, and undermines the medical system. Administrative responses initiated include action plans, monitoring systems, and guidelines. Common terminology among involved parties for defining and grading resistance is required. Multidrug-resistant microorganisms challenge clinical laboratories; uniform recommendations towards detection of resistance mechanisms need to be established. Prospective multicenter outcome studies comparing antibiotic regimens and containment methods are needed. Because new antimicrobials against Gram-negative pathogens are not foreseeable, judicious use of the existing and strict adherence to infection control best practice might restrain resistance spread. Awareness of resistance patterns and organisms prevailing locally by reporting laboratories and treating physicians is important.
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Estimation of seroprevalence of the pandemic H1N1 2009 influenza virus using a novel virus-free ELISA assay for the detection of specific antibodies.
Viral Immunol.
PUBLISHED: 06-15-2011
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The pandemic H1N1 2009 influenza A emerged in April 2009 and spread rapidly all over the world. In Greece, the first case of the pandemic H1N1 was reported on May 18, 2009, while a considerable increase in the number of cases was noticed at the beginning of July 2009. The need for surveillance of the immune status of the Greek population led us to develop a virus-free ELISA that specifically recognizes pandemic H1N1 2009 influenza virus antibodies in human sera. The method is based on the use of synthetic peptides (H1-pep and N1-pep) that are derived from the hemagglutinin and neuraminidase of the 2009 pandemic strain, respectively, and differentiate the swine-origin influenza A/California/14/2009 (H1N1) from the seasonal influenza A viruses. Serum samples were obtained from 271 healthy blood donors during May, November, and December 2009. Among sera collected during May, November, and December, IgG antibodies against the peptide H1-pep were detected in 7.4, 13.8, and 19.3% of the donors, respectively, while IgG antibodies against the peptide N1-pep were detected in 5.3, 9.6, and 16.9% of the donors, respectively. The application of the immunoassay indicated a time-dependent increase of the prevalence of anti-H1-pep and anti-N1-pep IgG antibodies during the pandemic H1N1 outbreak in Greece. The method could be also indicative for the discrimination of immune persons from those susceptible to infection with the pandemic H1N1 strain, as well as for the establishment of effective vaccination programs.
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Comparative evaluation of combined-disk tests using different boronic acid compounds for detection of klebsiella pneumoniae carbapenemase-producing enterobacteriaceae clinical isolates.
J. Clin. Microbiol.
PUBLISHED: 06-01-2011
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The accurate phenotypic detection of Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae is an increasing necessity worldwide. We evaluated the performance of boronic acid combined-disk tests using as substrate imipenem or meropenem and as inhibitor of KPC production 300 ?g aminophenylboronic acid (APBA), 600 ?g APBA, or 400 ?g phenylboronic acid (PBA). Tests were considered positive when an increase in the growth-inhibitory zone around a carbapenem disk with KPC inhibitor was 5 mm or greater of the growth-inhibitory zone diameter around the disk containing carbapenem alone. The comparison of the combined-disk tests was performed with 112 genotypically confirmed KPC-possessing Enterobacteriaceae isolates. To measure the specificity of the tests, 127 genotypically confirmed KPC-negative Enterobacteriaceae isolates that were nonsusceptible to at least one carbapenem were chosen for testing. Using disks containing imipenem without and with 300 ?g APBA, 600 ?g APBA, or 400 ?g PBA, 72, 92, and 112 of the KPC producers, respectively, gave positive results (sensitivities, 64.3%, 82.1%, and 100%, respectively). Using disks containing meropenem without and with 300 ?g APBA, 600 ?g APBA, or 400 ?g PBA, 87, 108, and 112 of the KPC producers, respectively, gave positive results (sensitivities, 77.7%, 96.4%, and 100%, respectively). Among KPC producers, the disk potentiation tests using meropenem and PBA demonstrated the largest differences in inhibition zones (P < 0.001). All combined-disk tests correctly identified 124 of the 127 non-KPC producers (specificity, 97.6%). This comparative study showed that PBA is the most effective inhibitor of KPC enzymes, and its use in combined-disk tests with meropenem may give the most easily interpreted results.
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Dissemination of clinical isolates of Klebsiella oxytoca harboring CMY-31, VIM-1, and a New OXY-2-type variant in the community.
Antimicrob. Agents Chemother.
PUBLISHED: 05-09-2011
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The aim of the present study was to investigate the epidemiological link of multidrug-resistant Klebsiella oxytoca isolates causing community-onset infections among patients attending our outpatient department and to investigate the underlying resistance mechanisms. The isolates were tested by agar dilution MICs, phenotypic carbapenemase testing, enterobacterial repetitive intergenic consensus-PCR, and pulsed-field gel electrophoresis (PFGE). PCR assays and nucleotide sequencing were employed for the identification of bla gene types and the mapping of the integron-containing metallo-?-lactamase (MBL) gene. During the study period (January 2005 to April 2007), nine broad-spectrum cephalosporin-resistant K. oxytoca clinical isolates were prospectively collected from separate outpatients with urinary tract infections. In all cases, the patients had been hospitalized or exposed to health care facilities during the preceding year. Molecular typing revealed that all isolates belonged to the same K. oxytoca clonal type, which contained five PFGE subtypes. A novel chromosomal OXY-2 ?-lactamase type variant (OXY-2-9) was detected in all isolates, but no mutations in the promoter region justifying bla(OXY) gene overproduction were detected. In addition, all isolates harbored the plasmidic CMY-31 (LAT-4) AmpC cephalosporinase, while three of them harbored VIM-1 MBL in a class 1 integron structure. This is the first study to present the dissemination in the community of multidrug-resistant K. oxytoca isolates causing extrahospital infections.
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Characterization of Enterobius vermicularis in a human population, employing a molecular-based method from adhesive tape samples.
Mol. Cell. Probes
PUBLISHED: 03-23-2011
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Human infection with the parasitic nematode Enterobius vermicularis occurs worldwide, particularly in children. Although its prevalence may exceed 35% in some parts of the world, molecular studies of E. vermicularis in humans are limited. The aim of the present study was to investigate the genetic variation within E. vermicularis in a human population. For this purpose, 77 adhesive tape samples taken from Greek children infested with E. vermicularis were tested. New primers were designed to amplify a segment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene of E. vermicularis from adhesive tape samples. Thirty-six amplicons were sequenced and eleven different haplotypes were identified. All sequences clustered within the type previously characterized (type B), only reported to date from captive chimpanzees. To the best of our knowledge, this is the first study of E. vermicularis genotypes from a human population.
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Vaccination of health-care workers against influenza: our obligation to protect patients.
Influenza Other Respir Viruses
PUBLISHED: 03-21-2011
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Nosocomial influenza poses a threat for specific groups of patients and is associated not only with the disruption of health-care services but also excess costs. Although vaccination of health-care workers (HCWs) has been recommended for almost three decades and constitutes the most convenient and effective means to prevent nosocomial transmission, vaccine uptake within this group remains unacceptably low worldwide. In regard to the pandemic influenza A H1N1, HCWs constitute a priority group for immunization. Nevertheless, low vaccination rates have been documented regarding the influenza pandemic and associated with the onset of nosocomial cases and outbreaks. HCWs, health-care institutions, and public health bodies have the moral obligation to protect vulnerable patients and therefore weigh the benefits of mandatory vaccination. Key effective interventions, such as the education of HCWs concerning the benefits and safety of influenza vaccination, the reinforcement of on-site, free of charge vaccinations, and the use of mobile vaccination teams in conjunction with incentives, should be widely implemented.
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Epidemiological characteristics of infections caused by Bacteroides, Prevotella and Fusobacterium species: a prospective observational study.
Anaerobe
PUBLISHED: 03-07-2011
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In order to investigate differences among infections due to Gram-negative anaerobic bacteria (Bacteroides, Prevotella and Fusobacterium spp.), clinical, epidemiological, and microbiological data were collected and evaluated from 206 anaerobic infections. The most frequently isolated species was Bacteroides fragilis. The majority of the cases were intra-abdominal infections (49%) followed by skin and soft tissue infections (24.7%). Logistic regression analysis showed that Bacteroides spp. strains were more often isolated from intra-abdominal infections (p = 0.002), whereas Prevotella spp. were isolated more frequently from cases with shorter duration of hospitalization (p = 0.026), and less frequently from bloodstream infections (p = 0.049). In addition, Bacteroides spp. were associated with coinfection due to Enterobacteriaceae species (p = 0.007), whereas Prevotella spp. were associated with coinfection due to Staphylococcus spp. (p = 0.002). Patients with an infection due to B. fragilis, were more frequently admitted in a general surgical ward (p = 0.017), or have been treated with a 2nd generation cephalosporin before anaerobic infection onset (p = 0.05). Total mortality was 10.9% and was associated with bacteremia (p = 0.026), and hematological (p = 0.028), or solid organ malignancy (p = 0.007). Metronidazole resistance was detected only among Prevotella spp. (16.2%) and B. fragilis group (0.8%) isolates. In conclusion, this study indicated differences between infections due to the most frequently isolated Gram-negative anaerobic species, differences that may affect the design and implementation of empirical antimicrobial chemotherapy guidelines.
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Treatment of viral conjunctivitis with antiviral drugs.
Drugs
PUBLISHED: 02-16-2011
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Viral conjunctivitis is one of the most common disorders observed in ophthalmic emergency departments, yet no established treatment exists. Lately, antiviral medications have been introduced into clinical practice; however, a systematic review focusing on their use and effectiveness in the treatment of viral conjunctivitis has not been previously reported. We systemically reviewed the literature to identify studies where antiviral drugs were used to treat viral conjunctivitis. Currently, aciclovir, trifluridine and valaciclovir are commonly used as antiviral agents to treat herpesvirus infections. Cidofovir has been used successfully to treat some cases of adenoviral conjunctivitis, although toxicity has also been reported. The use of other medications, such as idoxuridine, has been minimized in clinical practice due to their high toxicity. Interestingly, most of the antiviral drugs developed are used to treat herpesvirus infections, while less progress has been made in the field of adenoviral infections. For other viral causes of conjunctivitis, no effective remedy is currently available, and treatment focuses on the relief of symptoms. Caution should be exercised when coadministering other pharmacological agents, such as corticosteroids, because of emerging adverse effects.
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Seroepidemiological study of pandemic influenza H1N1 following the 2009-2010 wave in Greece.
Vaccine
PUBLISHED: 02-04-2011
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Knowledge of seroprevalence rates against 2009 pandemic H1N1 virus will assist vaccination recommendations and the preparation of the health-care system during subsequent years. This study was conducted in Greece during June-August 2010 to estimate the seroprevalence rate against pandemic H1N1 virus. Persons presenting in 29 health-care facilities across the country were studied. Seroprevalence was estimated employing a virus-free ELISA that specifically recognizes 2009 H1N1 virus antibodies in human sera. Sera collected from 2005 to April 2009 were also used to estimate pre-pandemic seroprevalence rates. A total of 954 persons were studied. The overall seroprevalence rate was 28.5% (95% confidence interval=25.6-31.3%). Age-specific rates were 34.2% in persons 0-4 years, 36.3% in persons 5-19 years, 25.0% in persons 20-39 years, 23.4% in persons 40-59 years, and 31.8% in persons ? 60 years. The highest rates were recorded in the Regions of Ionian Islands (67%) and Epirus (42.9%), while the lowest (8.4%) in the Region of Thessaly. Age-specific attack rates of infection during 2009-2010 were 28.8% in persons 0-4 years, 32.5% in persons 5-19 years, 14.3% in persons 20-39 years, 19.1% in persons 40-59 years, and 14.4% in persons ? 60 years. Multivariate analysis revealed that Region of residence and caring for children <5 years were associated with increased risk for seropositivity. Urbanity, personal and family characteristics, working in a health-care facility or in a school, history of pandemic H1N1 vaccination or history of influenza-like illness during 2009-2010 were not associated with increased risk for seropositivity.
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Detection of bacillus Galmette-Guérin (Mycobacterium bovis BCG) DNA in urine and blood specimens after intravesical immunotherapy for bladder carcinoma.
J. Clin. Microbiol.
PUBLISHED: 01-26-2011
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A real-time PCR targeting IS6110 was employed for the detection of Mycobacterium tuberculosis DNA in specimens collected from 10 patients treated with intravesical M. bovis bacillus Galmette-Guérin (BCG) immunotherapy for bladder malignancy. BCG DNA was detected in all urine specimens taken 24 h after the instillations, as well as in 24% of the specimens collected 7 days after the instillations; it was also detected in a single specimen taken 6 weeks after the last instillation. BCG DNA was detected in 8.3% of the blood specimens taken 1 day after instillation, and its amplification was associated with cases of self-limiting fever. These findings give indications that this real-time PCR is helpful to recognize BCG bacteremic cases, which may lead to mycobacterial infection.
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Activity of tigecycline alone and in combination with colistin and meropenem against Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae strains by time-kill assay.
Int. J. Antimicrob. Agents
PUBLISHED: 01-13-2011
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Antibiotic combinations including tigecycline have not been studied against Klebsiella pneumoniae carbapenemase (KPC)-producing pathogens. Tigecycline alone and combined with colistin and meropenem was tested against eight genetically unrelated KPC-producing clinical strains of Enterobacteriaceae (four K. pneumoniae, two Escherichia coli, one Enterobacter cloacae and one Serratia marcescens) by time-kill assay. Tigecycline displayed a concentration-independent bacteriostatic activity in seven strains and bactericidal activity in one strain. Colistin showed bactericidal activity at 4× the minimum inhibitory concentration (MIC) in three strains and was bacteriostatic for the remaining strains and concentrations. Meropenem was bactericidal in three strains and bacteriostatic in five strains. The tigecycline+meropenem combination was not bactericidal against the four K. pneumoniae strains and was non-synergistic against all eight strains. Tigecycline+colistin was bactericidal against all strains at most time intervals and concentrations and was also synergistic at 1× and 2× MIC against most strains up to 4-8h and at 4× MIC up to 24 h against all strains. These findings suggest that, at most drug concentrations, tigecycline, colistin and meropenem as single agents do not exhibit efficient bactericidal activity against most of the KPC-producing strains. Tigecycline alone might be a therapeutic option for infections caused by KPC-producers when bacteriostatic activity is adequate or combined with colistin when bactericidal activity is necessary. Additional in vivo tests are warranted to assess better the killing kinetics of tigecycline combinations against KPC-producers.
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Emergence of VIM-1 metallo-?-lactamase-producing Escherichia coli in a neonatal intensive care unit.
Microb. Drug Resist.
PUBLISHED: 11-30-2010
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A carbapenem-resistant Escherichia coli isolate was recovered from rectal swab of a 12-day-old female neonate, which was admitted to a Greek neonatal intensive care unit (NICU). Phenotypic testing, polymerase chain reaction assays with sequencing, and plasmid analysis revealed that the isolate harbored a plasmid-mediated bla(VIM-1) metallo-?-lactamase gene. The appearance of a metallo-?-lactamase-producing E. coli in NICU is worrisome. Further surveys are needed to determine whether such Enterobacteriaceae may also be spreading in other NICUs.
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Recurrent healthcare-associated community-onset infections due to Klebsiella pneumoniae producing VIM-1 metallo-beta-lactamase.
J. Antimicrob. Chemother.
PUBLISHED: 09-28-2010
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To investigate the extrahospital dissemination of carbapenem-resistant Klebsiella pneumoniae isolates and the mechanisms of acquired resistance.
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Adenovirus genome in the placenta: association with histological chorioamnionitis and preterm birth.
J. Med. Virol.
PUBLISHED: 06-24-2010
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Adenovirus is isolated frequently from the amniotic fluid and has been implicated in severe neonatal infections. A case control study was carried out to examine the association of detection of adenovirus in placentas with preterm birth and histological chorioamnionitis. Placentas from preterm and full term deliveries were collected prospectively. Preterm cases were divided into three subgroups according to the gestational age. PCR was carried out on placental tissues for the detection of adenovirus genome. Placentas were evaluated histologically for the presence of chorioamnionitis. Chi-square and odds ratios (OR) were used to determine if detection of adenovirus is associated with preterm birth and histological evidence of inflammation. Seventy-one preterm and 122 full term placentas were studied. Adenovirus genome was detected in 29 (40.8%) of preterm cases and in 25 (20.5%) of the full term controls (OR = 2.6; 95% CI, 1.4-5.1; P = 0.002). Detection of adenovirus in preterm placentas was significantly higher compared to full term particularly in the lower gestational age. Detection of adenovirus in placenta followed the seasonal variation of adenovirus infections. Thirty-seven preterm and 21 full term placentas were also selected for paraffin inclusion and histological examination. Chorioamnionitis was present more frequently in preterm adenovirus-positive placentas compared to preterm adenovirus-negative placentas (75% vs. 36%; P = 0.026) as well as compared to term adenovirus-positive placentas (75% vs. 19%; P = 0.003). This study demonstrates that adenovirus infection of the placenta is associated strongly with histological chorioamnionitis and preterm birth.
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A simple phenotypic method for the differentiation of metallo-beta-lactamases and class A KPC carbapenemases in Enterobacteriaceae clinical isolates.
J. Antimicrob. Chemother.
PUBLISHED: 06-11-2010
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The increasing frequency of class A KPC enzymes and class B metallo-beta-lactamases (MBLs) among Enterobacteriaceae as well as their possible co-production makes their early differentiation urgent.
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Detection of the new metallo-beta-lactamase VIM-19 along with KPC-2, CMY-2 and CTX-M-15 in Klebsiella pneumoniae.
J. Antimicrob. Chemother.
PUBLISHED: 06-03-2010
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To report the identification of the metallo-beta-lactamase (MBL) variant VIM-19 in a Klebsiella pneumoniae clinical strain co-producing KPC-2 carbapenemase, CMY-2 cephalosporinase and CTX-M-15 extended-spectrum beta-lactamase.
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Characteristics of meropenem heteroresistance in Klebsiella pneumoniae carbapenemase (KPC)-producing clinical isolates of K. pneumoniae.
J. Clin. Microbiol.
PUBLISHED: 05-26-2010
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Meropenem heteroresistance was investigated in six apparently meropenem-susceptible, Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-KP) clinical isolates, compared with that in carbapenemase-negative, meropenem-susceptible controls. In population analyses, the KPC-KP isolates grew at meropenem concentrations of 64 to 256 microg/ml. Heteroresistant colonies had significantly elevated expression of the bla(KPC) gene compared with the native populations but did not retain heteroresistance when subcultured in drug-free media. Time-kill assays indicated that meropenem alone was not bactericidal against KPC-KP but efficiently killed the control strains.
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In vivo acquisition of a plasmid-mediated bla(KPC-2) gene among clonal isolates of Serratia marcescens.
J. Clin. Microbiol.
PUBLISHED: 05-12-2010
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Three patients admitted to a Greek hospital were infected with Serratia marcescens isolates that exhibited reduced susceptibility to carbapenems and harbored Klebsiella pneumoniae carbapenemase (KPC) enzymes. In two of these cases, the patients were initially infected by carbapenem-susceptible S. marcescens isolates. Molecular typing and plasmid analysis suggested that all three patients had clonally indistinguishable isolates of S. marcescens that acquired a plasmid-mediated bla(KPC-2) gene during the hospitalization.
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In vitro bactericidal activity of human beta-defensin 2 against nosocomial strains.
Peptides
PUBLISHED: 05-03-2010
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Human beta-defensin 2 (hBD-2) is a 41-amino acid cationic peptide of the innate immune system that serves as antimicrobial molecule. We determined the bactericidal activity of synthetic hBD-2 against nosocomial strains belonging to eight different bacterial species and exhibiting various antimicrobial resistance phenotypes. The native disulfide connectivity was found essential for the bactericidal activity of hBD-2, while sodium chloride concentration was reversely associated with its potency. hBD-2 exhibited high bactericidal activity against Acinetobacter baumannii, Pseudomonas aeruginosa, Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus clinical strains. Characteristically, A. baumannii strains that exhibited multi-drug resistant (MDR) phenotypes were susceptible to lower concentrations of hBD-2 (vLD(90)=3.25-4.5 microg/ml) in comparison with non-MDR (wild-type) A. baumannii strains (vLD(90)=3.90-9.35 microg/ml). Bactericidal activity of hBD-2 was less pronounced against Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis strains but was significantly enhanced against strains of these species that exhibited resistance to several beta-lactam antibiotics. These observations give indications that the natural hBD-2 has a potential therapeutic role against bacterial pathogens and particularly against those exhibiting MDR phenotypes.
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Inhibitor-based methods for the detection of KPC carbapenemase-producing Enterobacteriaceae in clinical practice by using boronic acid compounds.
J. Antimicrob. Chemother.
PUBLISHED: 04-15-2010
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Enterobacteriaceae clinical strains that produce the class A carbapenem-hydrolysing enzyme KPC (Klebsiella pneumoniae carbapenemase) are increasingly reported worldwide, and are already endemic in North and South America, China, Israel and Greece. The accurate detection of KPC enzymes is of utmost importance for containing the global spread of KPC producers. Currently, the detection of putative carbapenemase production is based on an initial phenotypic screen for carbapenem resistance followed by the modified Hodge test (MHT) as a confirmatory test. However, the MHT is often difficult to interpret, is not specific for carbapenemase activity due to KPC and there are reports of false-positive results with CTX-M-positive or AmpC-hyperproducing Enterobacteriaceae. Boronic acid compounds are serine-type beta-lactamase inhibitors that were employed originally for the detection of class C plasmidic AmpCs in Enterobacteriaceae. Recently, they have also been evaluated for the differentiation of KPC-producing Enterobacteriaceae. In that respect, combined-disc tests using carbapenems with and without phenylboronic acid (PBA) have been proposed as the most accurate phenotypic tests for detecting KPC production. When these disc tests are extended to include carbapenem discs with EDTA or both PBA and EDTA on the same plate, the production of metallo-beta-lactamase (MBL) or both KPC and MBL, respectively, can also be accurately detected. Phenotypic tests based on the inhibitory activity of boronic acid compounds are very easy to perform and interpret, and may be applied from the first day of isolation of the suspected resistant Enterobacteriaceae. We think that they could effectively replace MHT for the convenient and early detection of KPC carbapenemases in regions where these enzymes are common.
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Risk factors and outcomes associated with acquisition of colistin-resistant KPC-producing Klebsiella pneumoniae: a matched case-control study.
J. Clin. Microbiol.
PUBLISHED: 04-07-2010
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A matched 1:3 case-control study investigated factors predicting colistin-resistant versus colistin-susceptible KPC-producing Klebsiella pneumoniae acquisition and its impact on patient outcomes. Case patients were more often admitted from other institutions (P = 0.019) and had longer therapy with beta-lactam/beta-lactamase inhibitors (P = 0.002) and higher overall mortality (P = 0.05). All 52 study isolates were clonally related, suggesting horizontal dissemination. None of these parameters independently predicted colistin resistance, which probably occurred in a susceptible KPC-KP strain that was subsequently disseminated horizontally.
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Chlamydia trachomatis serovar distribution and Neisseria gonorrhoeae coinfection in male patients with urethritis in Greece.
J. Clin. Microbiol.
PUBLISHED: 03-31-2010
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The distribution of Chlamydia trachomatis serovars and Neisseria gonorrhoeae coinfection was studied in a group of 100 C. trachomatis-positive males with urethritis in Greece. The serovar distribution revealed that apart from the predominant worldwide types E and F, the relatively uncommon type G is also prevalent. Gonococcal coinfection was frequent (30%) and was associated with genovariant Ja (75%, P = 0.008).
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Prevalence of Trichomonas vaginalis infection in women attending a major gynaecological hospital in Greece: a cross-sectional study.
J. Clin. Pathol.
PUBLISHED: 03-06-2010
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The prevalence of Trichomonas vaginalis is not accurately estimated, since it is not a reportable disease.
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Detection of mutations in the FemXAB protein family in oxacillin-susceptible mecA-positive Staphylococcus aureus clinical isolates.
J. Antimicrob. Chemother.
PUBLISHED: 02-14-2010
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Objectives Methicillin-resistant Staphylococcus aureus (MRSA) strains that express the mecA gene but are oxacillin susceptible (OS-MRSA; oxacillin MIC
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Heteroresistance to meropenem in carbapenem-susceptible Acinetobacter baumannii.
J. Clin. Microbiol.
PUBLISHED: 10-14-2009
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The characteristics of carbapenem heteroresistance were studied in 14 apparently carbapenem-susceptible Acinetobacter baumannii isolates. The MICs for carbapenems were determined, and the isolates were genotyped by pulsed-field gel electrophoresis (PFGE) and sequence typing (ST). Population analysis, testing of the stability of the heteroresistant subpopulations, and time-killing assays were performed. The agar dilution MICs of both imipenem and meropenem for the native isolates ranged from 0.25 to 4 mg/liter. The isolates belonged to nine PFGE types and exhibited seven ST allelic profiles. Population analysis revealed subpopulations that grew in the presence of imipenem at concentrations of up to 8 mg/liter and meropenem at concentrations of up to 32 mg/liter. The meropenem-heteroresistant subpopulations of 11 isolates exhibited stable resistance with MICs that ranged from 16 to >32 mg/liter; their PFGE profiles were identical to those of the native isolates. Time-kill assays with meropenem revealed less pronounced killing for 10 isolates. These findings indicate that meropenem pressure can produce meropenem-heteroresistant subpopulations that might subsequently select for highly resistant strains.
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Large dissemination of VIM-2-metallo-{beta}-lactamase-producing pseudomonas aeruginosa strains causing health care-associated community-onset infections.
J. Clin. Microbiol.
PUBLISHED: 09-23-2009
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During a 3-year period (May 2005 to April 2008), a series of 45 outpatients presented with community-onset urinary tract infections due to carbapenem-resistant Pseudomonas aeruginosa isolates. Forty of them had a history of previous hospitalization or exposure to healthcare facilities, while the remaining five had not been previously admitted to our healthcare facilities or elsewhere within the preceding 12 months. In 18 outpatients, the carbapenem-resistant organisms caused recurrent community-onset urinary tract infections, while in three outpatients the organisms were also implicated in bacteremic episodes. All 45 single-patient P. aeruginosa isolates harbored the bla(VIM-2) metallo-beta-lactamase (MBL) gene in a common class 1 integron structure. They belonged to one predominant pulsed-field gel electrophoresis type and three sporadically detected types; two of the sporadic clonal types were identified among outpatients without previous exposure to healthcare facilities, while the predominant clonal type was also identified to cause infections in hospitalized patients. This is the first study documenting that MBL-producing P. aeruginosa isolates cause community-onset infections that are related or not with exposure to healthcare facilities. Community-onset infections in our patients most likely resulted from the nosocomial acquisition of MBL producers, followed by a prolonged digestive carriage. The high rate of recurrent infections in the community underlies the difficulty of constraining infections caused by such microorganisms in the extrahospital setting.
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Use of boronic acid disk tests to detect extended- spectrum beta-lactamases in clinical isolates of KPC carbapenemase-possessing enterobacteriaceae.
J. Clin. Microbiol.
PUBLISHED: 09-02-2009
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We evaluated boronic acid (BA)-based methods for their ability to detect extended-spectrum beta-lactamases (ESBLs) among clinical isolates of KPC-producing members of the Enterobacteriaceae family. A total of 155 isolates of Klebsiella pneumoniae (n = 141), Escherichia coli (n = 6), Enterobacter aerogenes (n = 6), and Klebsiella oxytoca (n = 2) genotypically confirmed to be KPC producers were analyzed. As many as 118 isolates harbored ESBLs (103 harbored SHV-type ESBLs, 13 harbored CTX-M-type ESBLs, and 2 harbored both SHV- and CTX-M-type ESBLs); the remaining 37 isolates were genotypically negative for ESBL production. The CLSI ESBL confirmatory test was positive for 79 of the 118 ESBL producers (sensitivity, 66.9%), while all 37 non-ESBL producers were negative (specificity, 100%). When a > or =5-mm increase in the zone diameter of either the cefotaxime (CTX)-clavulanate (CA) or the ceftazidime (CAZ)-CA disks containing BA compared with the zone diameter of the CTX or CAZ disks containing BA was considered to be a positive result for ESBL production, the method detected all 118 ESBL producers (sensitivity, 100%) and showed no false-positive results for non-ESBL producers (specificity, 100%). Double-disk synergy tests, in which disks of CTX, CAZ, aztreonam, or cefepime in combination with BA were placed at distances of 20, 25, and 30 mm (center to center) from a disk containing amoxicillin (amoxicilline)-clavulanate-BA, were able to detect 116 (98.3%), 101 (85.6%), and 28 (23.7%) of the ESBL-positive isolates, respectively; no false-positive results for non-ESBL-producing isolates were detected. Our results demonstrate that the modified CLSI ESBL confirmatory test with antibiotic disks containing BA is the most accurate phenotypic method for the detection of ESBLs in Enterobacteriaceae producing KPC carbapenemases.
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Clonal spread of KPC-2 carbapenemase-producing Klebsiella pneumoniae strains in Greece.
J. Antimicrob. Chemother.
PUBLISHED: 06-13-2009
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KPC-possessing Klebsiella pneumoniae have been found to be widespread in several regions but are still rarely detected in Europe. We describe the characteristics of an outbreak caused by KPC producers in a tertiary care Greek hospital.
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Association of biofilm formation and methicillin-resistance with accessory gene regulator (agr) loci in Greek Staphylococcus aureus clones.
Microb. Pathog.
PUBLISHED: 06-12-2009
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Pathogenicity of Staphylococcus aureus is coordinated by the accessory gene regulator (agr) system. Previous studies suggested that agr Group II methicillin-resistant S. aureus (MRSA), a polymorphism that has been associated with moderate response to vancomycin, may also be related with overproduction of biofilm. In a hospital environment with endemic occurrence of MRSA, the distribution of agr groups and their association with biofilm formation was investigated. Forty-two MRSA and 32 methicillin-susceptible S. aureus (MSSA) isolates were tested and had derived from 10 genotypes and 8 clonal complexes. agr Groups I, II and IV were evenly distributed among MRSAs and MSSAs but agr Group III was not detected. agr Group II MRSAs showed significantly higher levels of biofilm production in comparison with MRSAs of the remaining agr groups as well as with all three agr groups of MSSAs. These findings suggest that agr Group II is simultaneously associated with methicillin-resistance and biofilm overproduction in a region with endemic MRSA.
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Carbapenem resistance in Acinetobacter baumannii: the molecular epidemic features of an emerging problem in health care facilities.
J Infect Dev Ctries
PUBLISHED: 03-25-2009
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Acinetobacter baumannii is an opportunistic gram-negative pathogen with increasing relevance in a variety of nosocomial infections especially among intensive-care-unit (ICU) patients. Carbapenems have been widely used to treat serious multidrug-resistant A. baumannii infections; however, incidences of carbapenem-resistant A. baumannii are rising in several parts of the world and large and sustained outbreaks caused by such bacteria have been described. Carbapenem-resistant A. baumannii epidemics are sustained by clusters of highly similar strains that successfully spread among different cities and countries; their resistance phenotype is mainly due to the acquisition of carbapenem-hydrolyzing class D beta-lactamase (CHDL) genes flanked by insertion sequence (IS) elements. Multi-facility outbreaks can be also sustained by inter-hospital transfer of colonized patients. Here, we review the global epidemiology of carbapenem-resistant A. baumannii, with the emphasis on the molecular epidemiology and genetic characterization of carbapenem resistance in epidemic strains.
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Evaluation of boronic acid disk tests for differentiating KPC-possessing Klebsiella pneumoniae isolates in the clinical laboratory.
J. Clin. Microbiol.
PUBLISHED: 02-28-2009
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The worldwide increase in the occurrence and dissemination of KPC beta-lactamases among gram-negative pathogens makes critical the early detection of these enzymes. Boronic acid disk tests using different antibiotic substrates were evaluated for detection of KPC-possessing Klebsiella pneumoniae isolates. A total of 57 genotypically confirmed KPC-possessing K. pneumoniae isolates with varying carbapenem MICs were examined. To measure the specificity of the tests, 106 non-KPC-possessing isolates (89 K. pneumoniae and 17 Escherichia coli isolates) were randomly selected among those exhibiting reduced susceptibility to cefoxitin, expanded-spectrum cephalosporins, or carbapenems. As many as 56, 53, and 40 of the non-KPC-possessing isolates harbored extended-spectrum beta-lactamases, metallo-beta-lactamases, and plasmid-mediated AmpC beta-lactamases, respectively. By use of CLSI methodology and disks containing imipenem, meropenem, or cefepime, either alone or in combination with 400 microg of boronic acid, all 57 KPC producers gave positive results (sensitivity, 100%) whereas all 106 non-KPC producers were negative (specificity, 100%). The meropenem duplicate disk with or without boronic acid demonstrated the largest differences in inhibition zone diameters between KPC producers and non-KPC producers. By use of disks containing ertapenem, all isolates were correctly differentiated except for five AmpC producers that gave false-positive results (sensitivity, 100%; specificity, 95.3%). These practical and simple boronic acid disk tests promise to be very helpful for the accurate differentiation of KPC-possessing K. pneumoniae isolates, even in regions where different broad-spectrum beta-lactamases are widespread.
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Global evolution of multidrug-resistant Acinetobacter baumannii clonal lineages.
Int. J. Antimicrob. Agents
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The rapid expansion of Acinetobacter baumannii clinical isolates exhibiting resistance to carbapenems and most or all available antibiotics during the last decade is a worrying evolution. The apparent predominance of a few successful multidrug-resistant lineages worldwide underlines the importance of elucidating the mode of spread and the epidemiology of A. baumannii isolates in single hospitals, at a country-wide level and on a global scale. The evolutionary advantage of the dominant clonal lineages relies on the capability of the A. baumannii pangenome to incorporate resistance determinants. In particular, the simultaneous presence of divergent strains of the international clone II and their increasing prevalence in international hospitals further support the ongoing adaptation of this lineage to the hospital environment. Indeed, genomic and genetic studies have elucidated the role of mobile genetic elements in the transfer of antibiotic resistance genes and substantiate the rate of genetic alterations associated with acquisition in A. baumannii of various resistance genes, including OXA- and metallo-?-lactamase-type carbapenemase genes. The significance of single nucleotide polymorphisms and transposon mutagenesis in the evolution of A. baumannii has been also documented. Establishment of a network of reference laboratories in different countries would generate a more complete picture and a fuller understanding of the importance of high-risk A. baumannii clones in the international dissemination of antibiotic resistance.
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Outbreak of OXA-48 carbapenemase-producing Klebsiella pneumoniae in Greece involving an ST11 clone.
J. Antimicrob. Chemother.
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First detected in Enterobacteriaceae isolates in Turkey, the OXA-48 carbapenemase has gradually disseminated in the wider Mediterranean area and Europe. Despite reports from other European regions, until now no such isolates have been detected in Greece. We describe the characteristics of the first outbreak caused by OXA-48-producing Klebsiella pneumoniae in Greece.
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Comparative evaluation of tigecycline susceptibility testing methods for expanded-spectrum cephalosporin- and carbapenem-resistant gram-negative pathogens.
J. Clin. Microbiol.
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We evaluated the Vitek2, Etest, and MIC Test Strip (MTS) methods of tigecycline susceptibility testing with 241 expanded-spectrum cephalosporin-resistant and/or carbapenem-resistant Enterobacteriaceae and Acinetobacter baumannii clinical isolates by using dry-form broth microdilution (BMD) as the reference method. The MIC(50/90)s were as follows: BMD, 1/4 ?g/ml; Vitek2, 4/?8 ?g/ml; Etest, 2/4 ?g/ml; MTS, 0.5/2 ?g/ml. Vitek2 produced 9.1/21.2% major errors, Etest produced 0.4/0.8% major errors, and MTS produced no major errors but 0.4/3.3% very major errors (FDA/EUCAST breakpoints). Vitek2 tigecycline results require confirmation by BMD or Etest for multidrug-resistant pathogens.
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High level of heterogeneity among Listeria monocytogenes isolates from clinical and food origin specimens in Greece.
Foodborne Pathog. Dis.
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In order to examine the genetic variation of clinical and food isolates of Listeria monocytogenes in Greece, a total of 61 L. monocytogenes non-duplicate isolates, recovered from clinical specimens (n=19) and food (n=42), were serotyped and genotyped using two different Random Amplification of Polymorphic DNA (RAPD) protocols and Multiple Locus Variable Number Tandem Repeat Analysis (MLVA). Serotype group 4b, 4d, 4e prevailed (39.4%), among both clinical and food isolates, followed by serotype group 1/2a, 3a (23.0%), which nevertheless was detected only among food isolates. The most discriminatory typing protocol was MLVA, which grouped four isolates into two pairs, while the remaining isolates produced unique fingerprints. Similar results were obtained when taking into account the combination of the two RAPD protocols (Simpson index 0.999); six isolates were grouped into three pairs, two of which were the pairs that were identified also by MLVA. Single use of each RAPD protocol resulted in inferior discrimination (Simpson index 0.978 and 0.997, respectively). In conclusion, the two molecular procedures, MLVA, and the combined RAPD protocols, produced similar results, showing that L. monocytogenes isolates from clinical and food specimens were highly heterogenous and that clustering was very uncommon.
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Pharmacokinetics of inhaled colistimethate sodium (CMS) in mechanically ventilated critically ill patients.
Intensive Care Med
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The purpose of this study was to describe inhaled colistin pharmacokinetics in patients with ventilator-associated tracheobronchitis (VAT) due to polymyxin-only susceptible Gram-negative bacteria (GNB).
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Imported Klebsiella pneumoniae carbapenemase-producing K. pneumoniae clones in a Greek hospital: impact of infection control measures for restraining their dissemination.
J. Clin. Microbiol.
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The recent emergence of carbapenemase-producing Enterobacteriaceae strains represents a major threat for hospitalized patients. We document the dissemination and control of carbapenemase-producing Klebsiella pneumoniae clones in a Greek hospital. During a 3-year study period (January 2009 to December 2011), carbapenemase-producing K. pneumoniae strains were isolated from clinical samples from 73 individual patients. Phenotyping and molecular testing confirmed that 52 patients were infected with K. pneumoniae carbapenemase 2 (KPC-2) producers, 12 were infected with VIM-1 producers, and the remaining 9 were infected with isolates producing both KPC-2 and VIM-1 enzymes. Twenty-eight of these clinical cases were characterized as imported health care associated, and 23 of these were attributed to KPC producers and 5 were attributed to KPC and VIM producers. The remaining 45 cases were deemed hospital acquired. In the second year of the study, intensified infection control intervention was implemented, followed by active surveillance and carrier isolation in the third year. The incidence of carbapenemase-producing K. pneumoniae patient cases decreased from 0.52/1,000 patient days in 2009 to 0.32/1,000 patient days in 2010 (P = 0.075). Following these additional infection control measures, the incidence fell to 0.21/1,000 patient days in 2011 and differed significantly from that in 2009 (P = 0.0028). Despite the fact that the imported cases of carbapenemase-producing K. pneumoniae were equally distributed over this 3-year period, the incidence of hospital-acquired cases decreased from 0.36/1,000 patient days in 2009 to 0.19/1,000 patient days in 2010 (P = 0.058) and to 0.1/1,000 patient days in 2011 (P = 0.0012). Our findings suggest that rigorous infection control measures and active surveillance can effectively reduce the incidence of secondary transmission due to KPC-producing pathogens.
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Oseltamivir-resistant influenza A(H1N1) 2009 virus in Greece during the post-pandemic 2010-2011 season.
Int. J. Antimicrob. Agents
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Information on the drug susceptibility of influenza epidemic strains is important for antiviral resistance monitoring. In Greece, the 2009-2010 pandemic waves were very mild and seroprevalence rates remained low after this influenza season, resulting in exclusive detection of the pandemic strain during the 2010-2011 influenza season. In the present study during the post-pandemic 2010-2011 season, 50 consecutive influenza A(H1N1) 2009 virus-positive samples from patients hospitalised in Greek hospitals were analysed for resistance to the neuraminidase inhibitor oseltamivir. All patients were hospitalised with severe influenza complications and had previously received oseltamivir. Influenza A(H1N1) 2009 virus detection and testing for oseltamivir resistance were performed with real-time PCR amplification assays. The H275Y substitution associated with resistance to oseltamivir was identified in two immunocompetent patients who received oseltamivir treatment for 3 days and 5 days, respectively. In both cases, patients were discharged in good condition despite development of resistance to antiviral treatment.
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In vitro antifungal susceptibility of filamentous fungi causing rare infections: synergy testing of amphotericin B, posaconazole and anidulafungin in pairs.
J. Antimicrob. Chemother.
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Mucormycetes (formerly known as zygomycetes of the order Mucorales) and hyaline moulds such as those of the genus Fusarium or Paecilomyces are emerging as significant human pathogens. The aim of the study was to determine the in vitro antifungal susceptibility of these fungi to older and newer antifungals and to investigate the antifungal activity of amphotericin B, posaconazole and anidulafungin in dual combinations.
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