Perineal Pyoderma Gangrenosum in a Patient with Inflammatory Bowel Disease: 1279

Purpose: Pyoderma gangrenosum (PG) is a neutrophilic dermatosis characterized by necrotic, violaceous ulcers that follow an aggressive, painful, and debilitating course. Lesions usually affect the lower extremities, but often involve other cutaneous regions, such as peristomal tissues. Identifying atypical PG in unusual locations is difficult as the diagnosis is one of exclusion. The differential diagnosis for perineal ulcers includes hidradenitis suppurativa, ecthyma gangrenosum, herpes simplex, cutaneous Crohn's disease, cutaneous tuberculosis, cutaneous lymphoma, vasculitis, lichen planus, and autoimmune blistering conditions. We describe a 60-year-old man with ulcerative colitis (UC) without prior extraintestinal manifestations who was post-colectomy for dysplasia and presented with perineal dermatosis 5 months after ileostomy closure. His post-operative course was marked by frequent bowel movements with urgency, tenesmus and subsequent perineal irritation. Despite local therapy and oral antibiotics, his perineal irritation progressed to excoriations, and then exquisitely painful ulcerations. He was then admitted and evaluated by a multidisciplinary team including gastroenterology, dermatology, infectious diseases and colorectal surgery. Minimal enteric inflammation limited to the pouch was seen on endoscopy and histopathology. Perineal biopsy showed non-specific neutrophilic inflammatory infiltrate. Wound cultures grew Pseudomonas aeruginosa. He was placed on IV antibiotics for possible ecthyma gangrenosum. After five days of nonresponse, it was felt that his lesions represented PG despite the indolent perineal disease course. IV steroids were added with no effect, and IV cyclosporine was then started with dramatic improvement over the next 2 weeks and resolution after 2 months on oral cyclosporine. Interestingly, the patient's gastrointestinal symptoms also began to subside. An outpatient pouchoscopy for recurrent diarrhea with pain on defecation revealed deep stellate lesions in the distal pouch, and the patient's IBD diagnosis was changed to Crohn's disease. The PG remained quiescent. He was transitioned from cyclosporine to infliximab. Atypical presentations of PG are a diagnostic dilemma for clinicians, and a broad differential diagnosis must be entertained, especially in IBD patients. We report here the first case in the literature of perineal PG in an adult IBD patient.Figure: No Caption available.