A Rare Case of Severe Post-operative Pyoderma Gangrenosum After Surgery for Perforated Diverticulitis at the Sigmoid Colon.

Pyoderma gangrenosum (PG) is a nonbacterial ulcerating skin condition. It is typically associated with other systemic disorders. However, approximately 20%-30% of cases are idiopathic. Post-operative PG (PPG) is a rare type of PG with a rapidly expanding cutaneous ulcer at a surgical site and is often misdiagnosed as a wound infection. The difficulty in diagnosis can lead to unnecessary surgical interventions and delay in the treatment of PG. Herein, we present the case of a 68-year-old patient with severe PPG with no underlying diseases. He underwent an emergency laparotomy (Hartmann's procedure) for perforated diverticulitis. After the operation, systemic inflammatory response syndrome (SIRS) developed and the skin around the incisional wound, stoma, injection venous lines, and electrocardiogram monitoring pads gradually became erythematous. Skin biopsy and the absence of a source of infection confirmed the diagnosis of PG. Drug therapy for PG with steroids, and tumor necrosis factor-α inhibitors improved SIRS and the patient recovered.