2025 Southeastern Residency Conference

Title: Dalbavancin Compared to Standard of Care for Acute Bacterial Skin and Skin Structure Infections in the Emergency Department
 
Authors: Liam Richardson, Katherine Weller, Christopher M. Bland, Jamie L. Wagner, Bruce M. Jones
 
Objective: By the end of this presentation participants will be able to describe the use of dalbavancin in the ED for ABSSSI admission avoidance, and discuss the clinical outcomes of dalbavancin compared to oral SOC antibiotics for treatment of ABSSSI in the ED
 
Self Assessment Question: Was there a significant difference in 30-day treatment failure between non-admitted patients treated with dalbavancin or oral SOC antibiotics for ABSSSI in the ED?
 
Background: Dalbavancin is a long-acting lipoglycopeptide antibiotic with broad gram-positive activity and is currently used per-protocol for admission avoidance and treatment of acute bacterial skin and skin structure infections (ABSSSIs) in both St. Joseph’s and Candler Hospital emergency departments (ED). There are limited data comparing clinical outcomes of dalbavancin and oral antibiotics for treatment of ABSSSIs in the ED. The aim of this study is to evaluate clinical outcomes of patients with ABSSSIs treated in the ED and not admitted with dalbavancin compared to oral antibiotics.
 
Methods: This retrospective quasi-experimental study evaluated clinical outcomes in ED patients treated with dalbavancin or oral antibiotics for cellulitis or abscess. The primary outcome was treatment failure, with a secondary outcome of adverse events reported. Patients who received oral antibiotics (the standard-of-care (SOC) group) (June 1, 2020–May 31, 2022) were identified using structured query language with ICD-10 codes for cellulitis (L03.XXX) and abscess (L02.XXX). Patients who received dalbavancin (June 1, 2022–September 1, 2024) were identified via a computer-generated list. Subjects were screened via random sampling for inclusion (ED visit for cellulitis/abscess without admission) and were matched 1:1 based on ICD-10 diagnoses. Demographics, infectious diagnosis, organism(s) isolated, infection-related labs, comorbidities, renal function, financial information, and antibiotics received were collected. Adverse events and culture/susceptibility data, if available, were recorded. Treatment failure was defined as hospital admission within 30 days or antimicrobial change due to the index infection. Data were collected and analyzed in Microsoft Excel. Categorical data were assessed using Chi-square or Fisher’s exact test, and continuous data with Student’s t-test or Mann-Whitney U, as appropriate. An alpha of 0.05 was deemed statistically significant.
 
Results: One hundred fifty patients (75 per group) were included. The median age was 56.5 years, and 50% were male. Most patients had cellulitis (136/150), with only 14 presenting with abscess as the primary diagnosis. Overall, 17 (22.7%) dalbavancin patients experienced treatment failure compared to 10 (13.3%) SOC patients (p = 0.137). Among those who failed treatment, the mean time to return was 4.8 days for dalbavancin patients versus 8.5 days for SOC patients (p=0.135). Prior oral antibiotic failure occurred in 54 (72%) dalbavancin patients and 15 (20%) SOC patients (p=<0.00001). Among SOC patients, cephalexin was the most prescribed discharge antibiotic (45%), followed by clindamycin (29.3%). A history of methicillin-resistant Staphylococcus aureus (MRSA) was present in 12 (16%) SOC patients and 7 (9.3%) dalbavancin patients. Positive cultures occurred in 10 (13.3%) dalbavancin patients (6 Staphylococcus aureus; 2 MRSA) versus 4 (5.3%) in the SOC group (3 Staphylococcus aureus; all MRSA). There were overall zero adverse events related to antibiotic therapy reported amongst both dalbavancin and SOC patients. Ten (13.3%) dalbavancin patients were un-insured compared to 22 (29.3%) SOC patients (p=0.0168). Mean inflation-adjusted reimbursement per patient was $4,478 for dalbavancin patients and $274 for the SOC patients. Additionally, 45/75 (60%) of dalbavancin patients had zero patient copay after insurance compared to 63/75 (84%) of SOC patients.
 
Conclusion: While dalbavancin had a numerically higher failure rate than SOC, more dalbavancin patients had failed prior SOC therapy, suggesting greater baseline infection severity; however, this study found no statistically significant difference in failure rates between the groups. Future studies controlling for other confounding variables, including prior treatment failures and more diverse infectious diagnoses should be performed to further evaluate these initial findings.