Cave canem: HBO2 therapy efficacy on Capnocytophaga canimorsus infections: a case series.

BACKGROUND: Dog bites are a frequent injury, but the incidence and type of lesions vary across countries. Although only few patients develop complications, the treatment of advanced injuries has a considerable medical, social and economic impact. A frequently isolated pathogen in dog bite wounds is Capnocytophaga canimorsus, a bacterium that can cause sepsis or meningitis. Hyperbaric oxygen (HBO2) therapy has been shown to be useful in treating anaerobic infections, most likely because it creates an inhospitable environment for the bacterium and enhances the patient's immune response. AIM: We present a case series of C. canimorsus infections treated with HBO2 in adjunction to antibiotic therapy. Furthermore, we tested the in vitro activity of ceftaroline against C. canimorsus, alone and in association with hyperbaric oxygen therapy. METHODS: We included nine (9) patients admitted to the surgery department of "A. Cardarelli" Hospital (Naples) after dog bite, from 2010 to 2016. All were initially treated with antibiotics and required transfer to the intensive care unit due to worsening conditions. C. canimorsus was isolated from wounds, and HBO2 therapy was administered in adjunction to antibiotics, until clinical improvement and microbiological test negativity. We tested the activity of hyperbaric oxygen therapy in adjunction to ceftaroline on cultured plates with C. canimorsus versus ceftaroline alone. Minimal inhibitory concentration was evaluated. CONCLUSIONS: Our findings confirm the utility of HBO2 therapy after biting injuries. Indeed, increased oxygen supply to the wound (as well as in vitro) may be toxic for bacteria, can improve healing and may improve the effectiveness of antibiotics.

Hyperbaric oxygen therapy reduces mortality in patients with Fournier's Gangrene. Results from a multi-institutional observational study.

BACKGROUND: Evidence about the clinical benefits of Hyperbaric Oxygen Therapy (HBOT) in patients with Fournier's Gangrene (FG) is controversial and inconclusive. We aimed to compare the mortality related to FG between patients undergoing surgical debridement and/or standard antibiotic therapy alone or in combination with HBOT. METHODS: We performed a retrospective multi-institutional observational case-control study. All patients admitted with diagnosis of FG from June 2009 to June 2019 were included into the study. Patients received surgical debridement and/or standard antibiotic therapy alone or in combination with HBOT. Factors associated with FG related mortality were assessed with uni-and multivariate analyses. The main outcome measure was FG related mortality. RESULTS: A total of 161 patients with diagnosis of FG were identified. Mean FG Severity Index was 8.6±4.5. All patients had broad-spectrum parenteral antibiotic therapy. An aggressive debridement was performed in 139 (86.3%) patients. A total of 72 patients (44.7%) underwent HBOT. Mortality due to FG was observed in 32 (36.0%) of patients who do not underwent HBOT and in 14 (19.4%) of patients who underwent HBOT (P=0.01). At the multivariate analysis, surgical debridement and HBOT were independent predictors of lower mortality while higher FG Severity Index was independent predictor of higher mortality. CONCLUSIONS: HBOT and surgical debridement are independent predictors of reduced FG related mortality.