Traumatic rectal perforation presenting as necrotising fasciitis of the lower limb

Necrotising fasciitis is a life-threatening soft tissue infection that is associated with high mortality and morbidity. It has been described in the form of Fournier's gangrene following rectal perforations related to colorectal cancer. In these rare instances, spontaneous perforation of locally-advanced rectal carcinoma provides an entry point for bacterial seeding to the surrounding soft tissues, resulting in Gram-negative sepsis of the perineum. To our knowledge, necrotising fasciitis extending beyond the perineum due to rectal perforation has not been previously described. We report an unusual self-induced traumatic rectal perforation presenting with severe necrotising fasciitis of the lower limb in a 73-year-old Chinese man. Our patient was successfully treated with a multidisciplinary approach that involved a defunctioning colostomy as well as prompt and rigorous debridement of the affected limb. We also review the literature on the management of retroperitoneal rectal perforations and their sequela, as well as discuss the various surgical options commonly applied and their outcomes.