Wound infection secondary to snakebite

Snakebites can produce severe local and systemic septic complications as well as being associated with significant overall morbidity and even mortality.

A prospective audit was undertaken to determine the bacterial causation of wound infection secondary to snakebite, and attempt to quantify the burden of disease.

The audit was undertaken at Ngwelezane Hospital, which provides both regional and tertiary services for north-eastern KwaZulu-Natal Province, South Africa, over a 4-month period. Records of patients who required surgical debridement for extensive skin and soft-tissue necrosis were analysed. At the time of debridement, tissue samples of necrotic or infected tissue were sent for bacteriological analysis as standard of care. Microbiology results were analysed.

A total of 164 patients were admitted to hospital for management of snakebite, of whom 57 required surgical debridement and 42 were included in the final microbiological analysis. Children were found to be the most frequent victims of snakebite; 57.8% of patients in this study were aged ≤10 years and 73.7% ≤15 years. Culture showed a single organism in 32/42 cases, two organisms in 8 and no growth in 2. Eight different types of organisms were cultured, five of them more than once. Thirty-five specimens (83.3%) grew Gram-negative Enterobacteriaceae, the most frequent being Morganella morganii and Proteus species. Thirteen specimens (31.0%) grew Enterococcus faecalis. Gram-negative Enterobacteriaceae showed 31.4% sensitivity to ampicillin, 40.0% sensitivity to amoxicillin plus clavulanic acid, 34.3% sensitivity to cefuroxime, 97.1% sensitivity to ceftriaxone, and 100% sensitivity to ciprofloxacin, gentamicin and amikacin. E. faecalis was 92.3% sensitive to amoxicillin, 92.3% sensitive to amoxicillin plus clavulanic acid, 100% sensitive to ciprofloxacin, 92.3% resistant to erythromycin and 100% resistant to ceftriaxone.

Children are particularly vulnerable to snakebite, and the consequences can be devastating. While the majority of patients in this study were shown to have secondary bacterial infection, debridement and subsequent wound management is considered the mainstay of treatment. Common organisms are Enterobacteriaceae and enterococci. There appears to be a role for antibiotics in the management of these patients. A good antibiotic policy is strongly advocated.