Necrotizing Fasciitis Within the First 72 Hours After Presentation With Skin and Skin Structure Infection

Abstract

Background. A small percentage of patients with serious skin infections later develop life‐threatening necrotizing fasciitis (NF), requiring prompt surgical debridement. Adjunctive diagnostic testing is needed to triage patients with skin infections at low risk of NF who could be safely discharged from the emergency department (ED) after antibiotic initiation. Elevated lactate has been associated with NF and mortality (lactate >2 or ≥6 mmol/L) and septic shock (≥2 mmol/L). Existing estimates of the frequency of NF are based on retrospective reviews and cases often lack testing for lactate. Methods. In 4 Phase 3 trials, 2883 adults with complicated (cSSSI) or acute bacterial (ABSSSI) skin and skin structure infections were randomized to dalbavancin or comparator, with multiple early and late follow up visits through Day 28. Baseline plasma lactates were prospectively collected in DUR001‐303 to assess an association with NF. We present the incidence of patients who later developed NF and their associated lactates. Results. NF was diagnosed in 3/2883 (0.1%) patients and all 3 survived (table). In the study with available baseline lactates (n = 623), 13/623 (2.1%) of patients had a lactate >4 mmol/L; 3/623 (0.5%) had a lactate ≥7 mmol/L, of whom one developed NF. NF was not seen in patients with a lactate ≤4 mmol/L, was seen in 1/13 (7.7%) with a level >4 mmol/L and 1/3 of those ≥7 mmol/L. Conclusion. NF incidence within 72 h of antibiotic initiation in cSSSI or ABSSSI patients was extremely low (0.1%) and occurred in 7.7% of those with lactate >4 mmol/ L. Lactate ≤4 mmol/L can be used to identify cSSSI or ABSSSI patients at low risk of NF, who could be safely discharged from the ED after antibiotic initiation.