Hierarchical Management of Chronic Infectious Diabetic Foot Wounds During the COVID-19 Pandemic: A Single-Center Retrospective Observational Study

Summary

Hierarchical management that combined telemedicine, risk stratification, multidisciplinary care, and infection-control measures enabled the continuous treatment of patients with diabetic foot during the COVID-19 pandemic, with no observed COVID-19 cases in this retrospective cohort.

Abstract

Coronavirus disease 2019 (COVID-19) has placed considerable pressure on healthcare systems worldwide and has disrupted the routine management of chronic diseases. Patients with diabetic foot often require repeated outpatient visits, hospitalization, and surgical intervention, making continuous wound care particularly challenging during the pandemic. This study aimed to describe the clinical characteristics of patients with diabetic foot treated during the COVID-19 pandemic and to summarize the hierarchical management strategy adopted at our institution. This single-center retrospective observational study included all consecutive patients with diabetic foot treated at our hospital between January 23 and March 27, 2020. Patient attendance during the study period was compared with that during the corresponding period in 2019. Demographic characteristics, comorbidities, Wagner classification, treatment strategies, and clinical outcomes were collected from electronic medical records and analyzed retrospectively. A total of 12 patients were treated during the study period, representing a marked reduction in hospital attendance compared with the corresponding period in 2019 (P < 0.0001). Most patients were older adults with multiple comorbidities, and 58% had Wagner grade 4–5 lesions. Surgical treatment was performed in eight patients, and the mean hospital stay was 27.5 days ± 20.2 days. No patient developed laboratory-confirmed COVID-19 during hospitalization or follow-up. One patient died of infectious shock secondary to diabetic foot infection, and the death was unrelated to COVID-19. Patients with diabetic foot often have advanced age, diabetes, multiple comorbidities, and chronic wounds that require ongoing medical care, which may increase their vulnerability during infectious disease outbreaks. The hierarchical management strategy described in this study allowed essential diabetic foot care to be maintained throughout the COVID-19 pandemic and was associated with no observed COVID-19 cases in this small retrospective cohort. Further studies involving larger populations are needed to evaluate its effectiveness and generalizability.

Introduction

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), rapidly evolved into a global pandemic and placed unprecedented pressure on healthcare systems worldwide¹. During the early stages of the pandemic, many healthcare resources were redirected toward infection control, resulting in reduced access to routine medical services for patients with chronic diseases². Although the acute phase of the pandemic has passed, the challenges encountered during this period have highlighted the importance of developing practical clinical workflows that ensure continuity of care during future public health emergencies. Lessons learned from COVID-19, therefore, remain relevant for emergency preparedness and healthcare system resilience^3,4.

Diabetic foot is one of the most serious complications of diabetes mellitus and is associated with chronic infection, peripheral neuropathy, peripheral arterial disease, and impaired wound healing^5,6. Patients frequently require regular wound assessment, debridement, vascular evaluation, antibiotic therapy, and, in severe cases, hospitalization or surgical intervention⁷. Delayed treatment may lead to progressive infection, major amputation, or death⁶. During the COVID-19 pandemic, routine outpatient services were substantially restricted, while travel limitations and concerns about hospital exposure further reduced patients' access to medical care⁸. Consequently, balancing infection prevention with the timely management of diabetic foot complications became a major challenge for clinicians worldwide. Recent international guidelines have emphasized the value of telemedicine, risk stratification, and multidisciplinary management to maintain essential diabetic foot services during infectious disease outbreaks^5,8.

Several studies have described the clinical characteristics and outcomes of patients with COVID-19 or diabetes during the pandemic^9,10. However, relatively few reports have provided a detailed, reproducible clinical workflow for managing diabetic foot patients who continued to require treatment under strict infection-control measures¹¹. Practical information regarding remote triage, hospital admission criteria, multidisciplinary decision-making, perioperative management, and follow-up has been limited. Because these procedures may be valuable for future infectious disease outbreaks or other situations in which healthcare resources are constrained, documenting an effective management pathway remains clinically relevant beyond the COVID-19 pandemic¹².

In this study, we retrospectively reviewed patients with diabetic foot treated at a designated COVID-19 hospital during the first epidemic wave in Zhejiang Province, China. We describe the hierarchical management strategy adopted at our institution, including telemedicine consultation, patient triage, hospital admission, multidisciplinary treatment, and follow-up. In addition, we summarize the clinical characteristics and short-term outcomes of this patient cohort. Rather than evaluating the effectiveness of the management strategy in preventing COVID-19 infection, this study aims to provide a practical, reproducible clinical workflow to assist healthcare providers in maintaining essential diabetic foot care during future public health emergencies.

Protocol

The study was conducted in accordance with the Declaration of Helsinki and was approved by the Medical Ethics Committee of the First Affiliated Hospital, Zhejiang University School of Medicine (Approval No. 2024-0844). Written informed consent was obtained from all patients for the use of clinical information and publication of clinical images.

Study design
This was a single-center retrospective observational study performed at the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China, which served as a designated COVID-19 treatment center during the first epidemic wave in Zhejiang Province. All consecutive patients with diabetic foot admitted between January 23 and March 27, 2020, were included. Patient attendance during this period was compared with that during the corresponding period in 2019.

Patient selection
Patients were eligible if they had a diagnosis of diabetic foot, were admitted during the study period, and had complete clinical records available for review. Patients were excluded if the diagnosis of diabetic foot could not be confirmed, if the medical records were incomplete, or if they received only online consultation without subsequent clinical evaluation. Clinical information was obtained from electronic medical records, nursing records, laboratory reports, imaging studies, and outpatient documentation.

Remote triage and hospital admission
During the COVID-19 pandemic, patients were encouraged to seek an initial consultation through the hospital telemedicine service or a secure a secure instant-messaging platform-based communication platform before visiting the hospital. The complete hierarchical management workflow is shown in Figure 1. Patients or their caregivers were instructed to submit standardized wound photographs, including dorsal, plantar, and lateral views of the affected foot, together with information regarding wound duration, drainage, odor, pain, fever, blood glucose control, current medications, and relevant medical history. When image quality or clinical information was insufficient, additional photographs or clarification were requested before further assessment.

All remotely submitted information was reviewed by the attending orthopedic surgeon and documented in the electronic outpatient medical record. Remote consultation records were used to support clinical triage; however, only information that was subsequently confirmed during in-person examination and recorded in the hospital electronic medical record was included in the retrospective study dataset. Patients who received online consultation alone without subsequent hospital evaluation were excluded from the present analysis.

Triage decisions were made by the attending orthopedic surgeon in accordance with institutional diabetic foot management protocols. Patients with superficial ulcers, stable wounds, no evidence of progressive infection, and Wagner grade 0–2 disease were advised to continue dressing changes, pressure offloading, glycemic control, and scheduled follow-up under remote guidance. Patients were referred for hospital assessment if they had suspected deep infection, rapidly progressive tissue necrosis, abscess formation, osteomyelitis, limb-threatening ischemia, systemic signs of infection, failure of outpatient treatment, or Wagner grade 3–5 disease.

Before hospital admission, all patients underwent institutional COVID-19 screening that included epidemiological history, body temperature measurement, symptom assessment, and routine laboratory evaluation. Chest computed tomography (CT) and/or SARS-CoV-2 reverse transcription polymerase chain reaction (RT-PCR) testing were performed according to the institutional screening protocol when patients had epidemiological risk factors, respiratory symptoms, fever of uncertain origin, or when admission or emergency surgery was planned.

Clinical assessment and treatment
After hospital admission, all patients underwent multidisciplinary evaluation involving orthopedic surgeons, endocrinologists, vascular surgeons, infectious disease specialists, rehabilitation physicians, and other specialists when clinically indicated. Clinical assessment included wound examination, Wagner classification, vascular assessment, laboratory investigations, microbiological testing when appropriate, and imaging studies, including radiography, ultrasonography, CT, or magnetic resonance imaging (MRI) according to clinical requirements. Treatment decisions were individualized according to wound severity, vascular status, and the patient's overall condition. Management options included conservative wound care, antibiotic therapy, surgical debridement, negative-pressure wound therapy, vascular intervention, minor or major amputation, and reconstructive procedures when limb salvage remained feasible. Standard infection-control precautions were maintained throughout hospitalization and all operative procedures.

Follow-up and outcome assessment
Patients were followed until April 1, 2020. Clinical outcomes were obtained from hospital records, outpatient follow-up, and telephone interviews with patients or their family members when necessary. The recorded outcomes included treatment modality, duration of hospitalization, laboratory-confirmed COVID-19 infection, wound status at discharge, and survival status. One patient died of infectious shock caused by diabetic foot infection, and the death was unrelated to COVID-19.

Statistical analysis
Continuous variables were presented as mean ± standard deviation (SD), and categorical variables were presented as number (percentage). The unit of analysis for the comparison of hospital activity was the daily number of hospitalized patients with diabetic foot. Daily inpatient counts recorded during the study period (January 23 to March 27, 2020) were compared with those recorded during the corresponding calendar period in 2019. Because February contained 29 days in 2020, the corresponding study period in 2019 extended from January 23 to March 28, resulting in 66 daily observations for each year.

Before parametric analysis, the distribution of daily inpatient counts was assessed using the Shapiro–Wilk test, and homogeneity of variances between the two study periods was evaluated using Levene's test. As the assumptions of approximate normality and equal variances were satisfied, an independent two-sample t-test was used to compare the mean daily number of hospitalized patients between the two study periods. Daily inpatient data were complete for both years, and no missing values were identified. Statistical analyses were performed using statistical analysis software. All statistical tests were two-sided, and P < 0.05 was considered statistically significant.

Results

Patient attendance during the COVID-19 pandemic
Between January 23 and March 27, 2020, a total of 12 patients with diabetic foot were hospitalized, compared with 35 patients during the corresponding period in 2019. The mean daily number of hospitalized patients was significantly lower during the COVID-19 pandemic than during the corresponding period in 2019 (Figure 2, P < 0.0001). The temporal distribution of daily hospitalized patients during the two study periods is shown in Figure 3.

Patient characteristics
The demographic and clinical characteristics of the patients are summarized in Table 1. The mean age was 72.5 ± 10.5 years, and ten patients (83%) were older than 60 years (Figure 4). Seven patients (58%) were women, and six (50%) required insulin therapy for glycemic control. Most patients had advanced disease at presentation. Seven patients (58%) had Wagner grade 4–5 lesions, and unilateral involvement was observed in nine patients (75%). Eight patients underwent surgery, including debridement, vascular intervention, or amputation, whereas four were managed conservatively (Figure 5). The mean length of hospital stay was 27.5 days ± 20.2 days. Hypertension and cardiovascular disease were each present in seven patients (58%). Other accompanying conditions included renal insufficiency, chronic pulmonary disease, cerebrovascular disease, and malignancy. The de-identified raw clinical data supporting the analyses presented in this study are provided in Supplementary File 1.

Clinical outcomes
No patient developed laboratory-confirmed COVID-19 during hospitalization or follow-up. During the same period, 17 patients hospitalized with COVID-19 also had diabetes mellitus. These patients were not included in the present study because none had diabetic foot disease. One patient died of infectious shock secondary to diabetic foot infection. No deaths were related to COVID-19.

Representative case
Figure 6A–C, Figure 7A–F, and Figure 8A,B show the treatment course of a representative patient and are intended to illustrate the clinical management pathway rather than the outcomes of the entire cohort. An 88-year-old woman with a Wagner grade 4 diabetic foot ulcer presented with gangrene of the fourth toe and extensive soft tissue infection. After COVID-19 had been excluded, she underwent staged surgical treatment consisting of repeated debridement, negative-pressure wound therapy, implantation of antibiotic-loaded bone cement, and local flap reconstruction. The wound gradually improved, and she was discharged without evidence of COVID-19 infection.

DATA AVAILABILITY:
The de-identified raw data supporting the findings of this study are provided as Supplementary File 1. All patient identifiers have been removed to protect participant privacy in accordance with institutional ethical requirements.

Figure 1: Workflow of the hierarchical management strategy for diabetic foot patients during the COVID-19 pandemic. Patients were initially evaluated through telemedicine consultation. Following remote assessment and Wagner classification, patients with Wagner grade 0–2 disease were managed at home with remote guidance and follow-up whenever appropriate. Patients with Wagner grade 3–5 disease or suspected deep infection were referred for hospital admission after COVID-19 screening. Hospitalized patients underwent multidisciplinary evaluation and individualized treatment, including wound debridement, vascular intervention, antibiotic therapy, or other surgical procedures as indicated. After discharge, all patients received outpatient or telephone follow-up. Please click here to view a larger version of this figure.

Figure 2: Comparison of the mean daily number of hospitalized patients with diabetic foot during the study periods in 2019 and 2020. The 2020 study period extended from January 23 to March 27. Because February had 29 days in 2020, the corresponding period in 2019 ran from January 23 to March 28, yielding 66 daily observations in each year. Error bars represent the standard deviation (SD). An independent two-sample t-test was used for comparison (P < 0.0001). Please click here to view a larger version of this figure.

Figure 3: Daily number of hospitalized patients with diabetic foot during the study periods in 2019 and 2020. The 2020 study period ran from January 23 to March 27, and the corresponding 2019 period ran from January 23 to March 28 to account for the leap year. The date axis represents the 2020 study period, with corresponding 2019 dates aligned for comparison. Please click here to view a larger version of this figure.

Figure 4: Age distribution of the study population. The bar chart shows the number of patients in each age group among the 12 patients included in the study. Please click here to view a larger version of this figure.

Figure 5: Distribution of treatment modalities among the study patients. The chart shows the number of patients who received conservative treatment or surgical treatment during hospitalization according to clinical assessment and multidisciplinary decision-making. Please click here to view a larger version of this figure.

Figure 6: Representative patient before surgical treatment. Clinical photographs show a representative 88-year-old woman with a Wagner grade 4 diabetic foot ulcer at the initial stage of treatment. (A) Dorsal view of the right foot obtained at the first outpatient evaluation, demonstrating gangrene of the fourth toe and surrounding soft tissue swelling. (B) Lateral view obtained immediately before the initial surgical debridement, showing progressive tissue necrosis. (C) Plantar view obtained before surgery, demonstrating plantar soft tissue involvement. This patient is presented as a representative case to illustrate the management protocol and does not represent the outcomes of the entire study cohort. Please click here to view a larger version of this figure.

Figure 7: Representative patient during staged surgical treatment. Serial intraoperative photographs show the different stages of limb-salvage treatment. (A,B) Wound appearance following the first surgical debridement with negative-pressure wound therapy. (C,D) Wound appearance after repeat debridement and placement of antibiotic-loaded bone cement for local infection control. (E,F) Wound appearance after local flap reconstruction before definitive wound healing. These images illustrate the sequential surgical procedures performed during hospitalization. Please click here to view a larger version of this figure.

Figure 8: Representative patient at hospital discharge. Clinical photographs were obtained at the completion of inpatient treatment. (A) Lateral view of the right foot demonstrating satisfactory wound healing after staged reconstruction. (B) Plantar view at discharge showing stable soft tissue coverage without evidence of recurrent infection. The patient was discharged in stable condition, and no laboratory-confirmed COVID-19 infection occurred during hospitalization. Please click here to view a larger version of this figure.

Characteristics		Total (n = 12)
Age, years		72.5 ± 10.5
	50–59	2 (17%)
Age range, years	60–69	2 (17%)
	70–79	5 (41%)
	≥80	3 (25%)
Sex	Male	5 (42%）
	Female	7 (58%）
Blood glucose control method	Diet	1 (8%)
	Oral medication	5 (42%)
	Insulin injection	6 (50%)
	Hypertension	7 (58%)
	Cardiovascular disease	7 (58%)
Comorbidity	renal insufficiency	3 (25%)
	Smoking	2 (17%)
	Others	4 (33%)
	0–1	2 (17%)
Wagner Grade	2–3	3(25%)
	4–5	7(58%)
	Single	9(75%)
Foot affected lesion	Bilateral	3(25%)
Treatment	Conservative treatment	4 (33%)
	vascular intervention	1 (8%)
	Debridement	2 (17%)
	Amputation	5 (42%)
Length of hospital stay (days)	27.5 ± 20.2
COVID-19 infection	0
Death	1 (8%)

Table 1: Demographics and clinical characteristics of patients with diabetic foot（Data are presented as mean ± SD or n (%)¹. As for comorbidities, cardiovascular disease included coronary heart disease(2 cases), cardiac insufficiency(2 cases), cerebral infarction(3 cases), and pulmonary heart disease(1 case), while other diseases include chronic obstructive pulmonary disease(2 cases), colon cancer(1 case), and rheumatoid arthritis(1 case). One patient died from infectious shock.

Supplementary File 1: De-identified raw clinical data of all patients included in the study. Patient identifiers have been removed to protect privacy.Please click here to download this file.

Discussion

The COVID-19 pandemic profoundly affected the delivery of routine medical care, particularly for patients with chronic diseases requiring continuous follow-up. Diabetic foot is a severe complication of diabetes mellitus that often requires regular wound assessment, infection control, vascular evaluation, and timely surgical intervention⁷. Delayed treatment has been associated with an increased risk of wound progression, major amputation, and mortality⁵. During the pandemic, ensuring access to essential diabetic foot care while minimizing the risk of SARS-CoV-2 exposure became a major challenge for clinicians¹³.

To address these challenges, the institution adopted a hierarchical management strategy incorporating telemedicine, risk stratification, multidisciplinary assessment, and strict infection-control measures^8,13. Although the number of hospitalized patients decreased during the study period, patients with severe infection or limb-threatening disease continued to receive timely inpatient care. No patient in the present cohort developed laboratory-confirmed COVID-19. However, because this was a retrospective observational study without a control group, these findings do not establish that the management strategy itself prevented SARS-CoV-2 infection. Instead, they indicate that essential diabetic foot services were maintained, with no observed COVID-19 cases in this small cohort.

Our experience is consistent with recommendations from the International Working Group on the Diabetic Foot (IWGDF), which emphasized remote consultation, patient triage, and maintaining essential diabetic foot services while prioritizing hospital resources for patients requiring urgent assessment⁵. Similar recommendations were also reported by other expert groups during the COVID-19 pandemic, highlighting telemedicine as an effective approach for follow-up and early clinical assessment while reserving hospital resources for patients requiring urgent intervention⁸. These principles remain applicable beyond the COVID-19 pandemic and may help maintain continuity of care during future public health emergencies or other situations in which healthcare resources are limited¹³.

Several limitations should be considered. First, this was a single-center retrospective study with a relatively small sample size, which limits the generalizability of the findings. Second, no comparison group was available, making it impossible to determine whether the management strategy improved clinical outcomes or reduced the risk of COVID-19 infection. Third, follow-up was limited to hospitalization and the early recovery period; long-term outcomes, such as wound healing, limb salvage, functional recovery, and quality of life, were not evaluated. Finally, the hospital was designated as a COVID-19 treatment center in Zhejiang Province, where the epidemiological situation differed from that in areas with a higher disease burden, such as Wuhan. These factors should be considered when interpreting the findings.

Patients with diabetic foot frequently require continuous wound care, repeated clinical assessment, and multidisciplinary management, making the maintenance of essential medical services particularly important during public health emergencies. In this single-center retrospective cohort study, the hierarchical management pathway, incorporating telemedicine, risk stratification, multidisciplinary assessment, and infection control measures, enabled the continuation of diabetic foot care throughout the COVID-19 pandemic. No laboratory-confirmed COVID-19 cases were observed among the patients included in this study.

However, these findings should be interpreted with caution. Because this was a retrospective observational study with a small sample size and no control group, the present study cannot determine whether the management strategy reduced SARS-CoV-2 infection, prevented exposure, or improved clinical outcomes. Rather, it describes a practical clinical workflow that supported continuity of diabetic foot care during the pandemic. Further prospective multicenter studies with larger patient populations are required to evaluate the effectiveness and generalizability of this management pathway during future public health emergencies.

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Personal protective equipment (PPE)	3M, St. Paul, MN, USA	Various	Used by healthcare personnel during patient evaluation and surgery.
Surgical gloves	Ansell Healthcare, Melbourne, Australia	Various	Sterile disposable gloves for surgical procedures.
Sterile surgical drapes	Molnlycke Health Care, Gothenburg, Sweden	Various	Used to maintain a sterile operative field.
Surgical instrument set	Local hospital supply	N/A	Standard instruments for wound debridement and soft tissue surgery.
Negative-pressure wound therapy (NPWT) system	3M + KCI, San Antonio, TX, USA	V.A.C. Therapy System	Applied after surgical debridement when indicated.
Antibiotic-loaded bone cement	Heraeus Medical, Wehrheim, Germany	PALACOS® R+G	Used for local infection control in selected patients.
Normal saline (0.9%)	Baxter Healthcare, Deerfield, IL, USA	Various	Used for wound irrigation.
Sterile gauze dressing	3M, St. Paul, MN, USA	Various	Routine wound dressing after debridement.
Chest computed tomography (CT) scanner	Siemens Healthineers, Erlangen, Germany	N/A	Performed for COVID-19 screening when clinically indicated.
SARS-CoV-2 RT-PCR assay	Local clinical laboratory	N/A	Laboratory confirmation of COVID-19 according to institutional protocols.
Electronic medical record (EMR) system	Hospital Information System	N/A	Source of demographic, laboratory, imaging, and follow-up data.
Smartphone or telemedicine platform	WeChat (Tencent, Shenzhen, China)	N/A	Used for remote consultation, wound image transmission, and follow-up.
Digital camera	Canon Inc., Tokyo, Japan	Various	Documentation of wound progression and representative clinical images.
SPSS Statistics Version 23.0	IBM Corp., Armonk, NY, USA	Version 23.0	Statistical analysis.