Isolated Cutaneous Perianal Crohn Disease With Rare Perineal Involvement

We present a rare case of isolated perianal Crohn disease (iPCD) with perineal involvement in a 28-year-old woman who remained free of luminal gastrointestinal symptoms for more than 10 years. The diagnosis was significantly delayed due to clinical overlap with hidradenitis suppurativa and pilonidal disease. The patient had multiple unsuccessful treatments, including antibiotics, immunosuppressants, and biological agents. Complete remission was ultimately achieved with combination therapy using infliximab and azathioprine. This case underscores the importance of early recognition, accurate differentiation from mimicking conditions, and a multidisciplinary approach to managing iPCD.