S4986 Cronkhite-Canada Syndrome: An Inflammatory Bowel Disease Mimic

Introduction: Cronkhite-Canada syndrome (CCS) is an extremely rare, non-hereditary polyposis syndrome, characterized by diffuse gastrointestinal hamartomatous polyps, along with ectodermal abnormalities such as alopecia, onychodystrophy, and skin hyperpigmentation. There are fewer than 500 cases reported worldwide since it was first described in 1955. We present a case of CCS initially diagnosed as Crohn’s disease highlighting its unique clinical and endoscopic features. Case Description/Methods: A 60-year-old African American woman presented with a 2-year history of watery diarrhea, abdominal pain, as well as progressive weight loss and malnutrition requiring enteral feeding. She was diagnosed as having Sjogren’s syndrome as well as Crohn’s disease and was treated with adalimumab and azathioprine following evaluation by multiple specialists but failed to improve and subsequently sought a second opinion at our institution. Her symptoms were also associated with alopecia, nail loosening, and hyperpigmentation. Laboratory markers and stool studies were unremarkable except for marked eosinophilia. Esophagogastroduodenoscopy revealed a normal esophagus, and markedly edematous, erythematous, and nodular gastric mucosa, most prominent in the body and antrum, along with diffuse nodular mucosa throughout the duodenum. Sigmoidoscopy showed similar findings in the rectum and sigmoid colon. Gastric, duodenal, and colonic biopsies confirmed the presence of hamartomatous polyps. Discussion: CCS is most commonly reported in middle-aged adults. Its etiology remains unclear, though an autoimmune component has been suggested given its association with other autoimmune conditions and increased levels of IgG-4 positive plasma cells in polyps. Recent transcriptomic analyses of CCS polyps have also shown upregulation of innate immune pathways. Early recognition is critical, as delayed diagnosis can lead to significant nutritional deficiencies and increased gastrointestinal malignancy risk and morbidity. Treatment entails nutritional support as well as corticosteroids, with gradual tapering based on clinical response, and steroid-spearing agents like azathioprine. Most patients experience improvement in both gastrointestinal symptoms and ectodermal abnormalities with treatment. Our case underscores the importance of considering CCS in patients presenting with gastrointestinal symptoms suspicious for Crohn’s disease. The presence of typical dermatologic features can lead to an earlier diagnosis.