continuous-manual-exchange-transfusion-for-patients-with-sickle-cell

Continuous Manual Exchange Transfusion for Patients with Sickle Cell Disease: An Efficient Method to Avoid Iron Overload

Children with sickle cell anemia (SCA) may be at risk of cerebral vasculopathy and strokes, which can be prevented by chronic transfusion programs. ...

Robert Debré Hospital, AP-HP

Bacterial infection is frequent in patients with sickle cell disease. Pneumococcal bacteremia is particularly severe in young children. The risk persists in adults, especially for nosocomial infections. Prevention is directed against pneumococcal disease and includes both vaccination and prophylactic antibiotics.

[Infection in sickle cell disease].

Cerebral arteriopathy can be detected in children with sickle cell disease (SCD) by transcranial Doppler (TCD). Abnormally high velocities are predictive of high stroke risk, which can be reduced by transfusion therapy. We report the results of the screening of 291 SCD children followed in our center, including the clinical and imaging follow-up of 35 children with abnormal TCDs who were placed on transfusion therapy. We postulated that patients with normal MRA findings and abnormal TCD velocities that normalized on a transfusion program could be safely treated with hydroxyurea (HU). We report their outcome (median follow-up of 4.4 years). Of 13 patients with normalized velocities on transfusion, 10 had normal MRAs, and transfusion therapy was stopped and HU begun. Four of these ten patients redeveloped high velocities off transfusion, so currently only six remain transfusion-free. Six other transplanted patients remain transfusion-free. Abnormal TCD velocities detect a high-risk group, justifying the research for suitable transplant donors. Multicenter studies comparing HU therapy to long-term transfusion might help identify which patients can avoid transfusion and its complications while avoiding vasculopathy.

Long-term follow-up of pediatric sickle cell disease patients with abnormal high velocities on transcranial Doppler.

To evaluate safety and immunogenicity of the pneumococcal 7-valent conjugate vaccine (PCV7) when administered to infants with sickle cell disease (SCD) at 2, 3, and 4 months of age with a booster dose of a 23-valent pneumococcal polysaccharide vaccine (PS-23) at 15 to 18 months of age.

Immunogenicity and safety of a pneumococcal conjugate 7-valent vaccine in infants with sickle cell disease.

Pediatricians taking care of sickle cell children in France are concerned about giving travel advice. Very few articles are published and no study has been done about it. A lot of pediatricians are using their own experience to decide if sickle cell children can travel abroad. Studying the consequences of such travel for sickle cell children is important to discuss common recommendations.

Sickle cell children traveling abroad: primary risk is infection.

Transcranial Doppler (TCD) is used to detect children with sickle cell anemia (SCA) who are at risk for stroke, and transfusion programs significantly reduce stroke risk in patients with abnormal TCD. We describe the predictive factors and outcomes of cerebral vasculopathy in the Créteil newborn SCA cohort (n = 217 SS/Sβ(0)), who were early and yearly screened with TCD since 1992. Magnetic resonance imaging/magnetic resonance angiography was performed every 2 years after age 5 (or earlier in case of abnormal TCD). A transfusion program was recommended to patients with abnormal TCD and/or stenoses, hydroxyurea to symptomatic patients in absence of macrovasculopathy, and stem cell transplantation to those with human leukocyte antigen-genoidentical donor. Mean follow-up was 7.7 years (1609 patient-years). The cumulative risks by age 18 years were 1.9% (95% confidence interval [95% CI] 0.6%-5.9%) for overt stroke, 29.6% (95% CI 22.8%-38%) for abnormal TCD, which reached a plateau at age 9, whereas they were 22.6% (95% CI 15.0%-33.2%) for stenosis and 37.1% (95% CI 26.3%-50.7%) for silent stroke by age 14. Cumulating all events (stroke, abnormal TCD, stenoses, silent strokes), the cerebral risk by age 14 was 49.9% (95% CI 40.5%-59.3%); the independent predictive factors for cerebral risk were baseline reticulocytes count (hazard ratio 1.003/L × 10(9)/L increase, 95% CI 1.000-1.006; P = .04) and lactate dehydrogenase level (hazard ratio 2.78/1 IU/mL increase, 95% CI1.33-5.81; P = .007). Thus, early TCD screening and intensification therapy allowed the reduction of stroke-risk by age 18 from the previously reported 11% to 1.9%. In contrast, the 50% cumulative cerebral risk suggests the need for more preventive intervention.

Impact of early transcranial Doppler screening and intensive therapy on cerebral vasculopathy outcome in a newborn sickle cell anemia cohort.

Acute splenic sequestration crisis (ASSC) is an unpredictable life-threatening complication of sickle cell disease (SCD) in infants. Here, our objective was to update available clinical information on ASSC. We retrospectively studied the 190 patients who were diagnosed at birth with SS or Sbeta(0) in the Paris conurbation between 2000 and 2009 and who experienced ASSC. They had 437 ASSC episodes (0.06/patient-year). Median age at the first episode was 1.4 years (0.1-7) and 67% of patients had more than one episode. Age was the only factor predicting recurrence: the risk was lower when the first episode occurred after 2 years versus before 1 year of age (hazard ratio, 0.60; 95% confidence interval, 0.41-0.88; P=0.025). A concomitant clinical event was found in 57% of episodes. The mortality rate was 0.53%. The treatment consisted in watchful waiting without prophylactic blood transfusions or splenectomy in 103 (54%) patients and in a blood transfusion programme in 55 (29%) patients. Overall, splenectomy was performed in 71 (37%) patients, at a median age of 4.5 years (range, 1.9-9.4). In conclusion, aggressive treatment may be warranted in patients experiencing ASSC before 2 years of age. Randomized controlled trials are needed to define the best treatment modalities.

Acute splenic sequestration crisis in sickle cell disease: cohort study of 190 paediatric patients.

We conducted a retrospective study on newborns with sickle-cell disease (SCD), born 1995-2009, followed in a multicentre hospital-based network. We assessed patient outcomes, medical care and compliance with the national guidelines published in December 2005. Data from 1033 patients (742 SS/Sβ°-thalassaemia) with 6776 patient-years of follow-up were analysed (mean age 7·1 ± 3·9 years). SCD-related deaths (n = 13) occurred only in SS-genotype patients at a median age of 23·1 months, mainly due to acute anaemia (n = 5, including 2 acute splenic sequestrations) and infection (n = 3). Treatment non-compliance was associated with a 10-fold higher risk of SCD-related death (P = 0·01). Therapeutic intensification was provided for all stroke patients (n = 12), almost all patients with abnormal transcranial Doppler (TCD) (n = 76) or with >1 acute chest syndrome/lifetime (n = 64) and/or ≥3 severe vaso-occlusive crises/year (n = 100). Only 2/3 of patients with baseline haemoglobin <70 g/l received intensification, mainly for other severity criteria. Overall, hydroxycarbamide was under-prescribed, given to 2/3 of severe vaso-occlusive patients and 1/3 of severely anaemic patients. Nevertheless, introduction of the on-line guidelines was concomitant with an improvement in medical care in the 2006-2009 cohort with a trend towards increased survival at 5 years, from 98·3% to 99·2%, significantly increased TCD coverage (P = 0·004) and earlier initiation of intensification of therapy (P ≤ 0·01).

Article	Year
[Infection in sickle cell disease]. La Revue du praticien\| PubMed ID: 15558970	2004
Long-term follow-up of pediatric sickle cell disease patients with abnormal high velocities on transcranial Doppler. Pediatric radiology\| PubMed ID: 15703901	2005
Immunogenicity and safety of a pneumococcal conjugate 7-valent vaccine in infants with sickle cell disease. The Pediatric infectious disease journal\| PubMed ID: 18043446	2007
Sickle cell children traveling abroad: primary risk is infection. Journal of travel medicine\| PubMed ID: 19674265	2009
Impact of early transcranial Doppler screening and intensive therapy on cerebral vasculopathy outcome in a newborn sickle cell anemia cohort. Blood\| PubMed ID: 21068435	2011
Acute splenic sequestration crisis in sickle cell disease: cohort study of 190 paediatric patients. British journal of haematology\| PubMed ID: 22224796	2012
Improvement of medical care in a cohort of newborns with sickle-cell disease in North Paris: impact of national guidelines. British journal of haematology\| PubMed ID: 27062606	2016

Emmanuelle Lesprit

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