Microbiological aspects of Fournier's gangrene

Fournier's gangrene (FG) is a devastating disease that is characterized by necrotizing fasciitis of the perineal, genital, or perianal region. Broad-spectrum antibiotics are the key component of its treatment. However, there is paucity of data regarding the optimal empirical antibiotherapy for FG.

Data from patients who underwent surgery for FG between January 2007 and December 2012 were retrieved from a prospectively collected departmental FG database. Demographics, clinical characteristics, causative pathogens and drug susceptibility/resistance were evaluated.

Fifty patients with a median age of 58.5 (22-83) years were included. The perianal origin (58%) was most commonly affected. A positive growth was found in specimen cultures of 48 (96%) patients. The median number of bacterial strains that grew in the cultures was 3 (0-10). Amikacin was the antibiotic with the highest frequency of sensitivity (74%), while the highest resistance was observed against ampicillin-sulbactam (64%). Escherichia coli was the most common microorganism (72%). Acinetobacter baumannii and Klebsiella pneumonia were significantly more common in patients who required mechanical ventilation. The mortality rate was 26%. An Uludag Fournier's Gangrene Severity Index (UFGSI) score of >9.5 and ventilatory support requirement were factors associated with an increased rate of mortality. Acinetobacter baumannii was the only microorganism which was associated with an increased mortality rate.

Causative pathogens in FG appeared to be shifting; thus, empirical antibiotic treatment for this disease should be modified. We recommend 3rd-generation cephalosporin, metronidazole and amikacin for empirical therapy.