Gas gangrene due to Clostridium perfringens in two injecting drug users in Vienna, Austria.

We describe two cases of severe myonecrotic infections caused by Clostridium perfringens in injecting drug users (IDUs) in Vienna, Austria. Clostridial myonecrosis, or gas gangrene, is a clostridial infection primarily of muscle tissue. C. perfringens is isolated in 90% of these infections. Other clostridial species isolated are C. novyi, C. septicum, C. histolyticum, C. fallax, and C. bifermentans. Classically, clostridial myonecrosis has an acute presentation and a fulminant clinical course. It is diagnosed mainly on a clinical basis. The infection may be so rapidly progressive that any delay in recognition or treatment may be fatal. The onset is sudden, often within 4 to 6 hours after an injury. An early clinical finding is sudden severe pain in the area of infection. Swelling and edema in the area of infection is pronounced. At surgery, the infected muscle is dark-red to black, is noncontractile, and does not bleed when cut. Crepitus, although not prominent, is sometimes detected. We were able to demonstrate spores that were morphologically indistinguishable from spores of C. perfringens in a drug sample obtained from case 2. General practitioners and accident and emergency staff should be aware of the possibility of C. perfringens infection in IDUs, especially if injection into soft tissue is suspected.