Bacteriological studies of gas gangrene and related infections

Gas gangrene, a life threatening condition is predominantly caused by Clostridium spp. Over a five year period (1996-2000), 580 wound swabs were processed from patients who had vehicular accidents with crush injury. The specimens were processed for anaerobic and aerobic organisms by standard laboratory techniques. Of the 580 swabs, 55(9.48%) were primary smear positive for spore bearing bacteria, of which 48 grew Clostridium spp. They were the sole anaerobic isolates in 30 patients (62.5%) whereas Clostridium spp. along with nonsporing anaerobes were isolated in 18 patients. Clostridium perfringens was the predominant isolate in 39 out of 48 cases (81.3%). However, 16 wound swabs which were primarily smear negative for spore bearers, grew Bacteriodes fragilis (11) and Fusobacterium species (5). All these 16 patients had foul smelling discharge with crepitation in the tissues. Our study highlights that apart from Clostridium spp., non-clostridial crepitant infections may present as myonecrosis simulating gas gangrene.