RT Journal Article SR Electronic T1 Case to highlight a rare differential diagnosis of necrotising fasciitis in the presence of a stoma: peristomal pyoderma gangrenosum JF BMJ Case Reports JO BMJ Case Reports FD BMJ Publishing Group Ltd SP e237534 DO 10.1136/bcr-2020-237534 VO 14 IS 5 A1 Cheryl Chong A1 Prasad Palanisamy A1 Eugene Shen-Ann Yeo YR 2021 UL http://casereports.bmj.com/content/14/5/e237534.abstract AB Peristomal pyoderma gangrenosum (PPG) is a rare clinical entity, which can masquerade as the more common and lethal necrotising fasciitis. The authors present a case of PPG in a 65-year-old woman who underwent robotic abdominoperineal resection for low rectal carcinoma and returned 8 days postoperation for peristomal skin ulcerations and pain, accompanied by leucocytosis; thus, she was treated as per necrotising fasciitis and underwent surgical debridement. Thereafter, her wound continued to worsen despite conventional wound care with vacuum-assisted closure and demonstrated signs of pathergy. The case was referred to dermatology where a diagnosis of PPG was made. This case report presents a cautionary tale for fellow clinicians, highlights the diagnostic challenge, and presents an updated literature review on diagnosis and management of this unique condition.