Encapsulating Peritoneal Sclerosis Mimicking Intra-abdominal Malignancy: A Case Report

Encapsulating peritoneal sclerosis (EPS) is an uncommon fibroinflammatory disorder characterized by extensive peritoneal fibrosis and, in characteristic cases, partial or complete encasement of bowel loops.We report a 62-year-old male with cirrhosis, hypertension, and type 2 diabetes mellitus who developed progressive severe abdominal pain, diarrhea, and reduced oral intake while undergoing investigation for weight loss and suspected gastrointestinal malignancy.Physical examination revealed a rigid, distended, and tender abdomen.Recovered laboratory findings included a C-reactive protein level of 62.2 mg/L, hemoglobin of 9.1 g/dL, platelet count of 85,000/µL, and serum creatinine of 2.9 mg/dL.Preoperative contrast-enhanced computed tomography demonstrated mesogastric peritoneal thickening, an adjacent 14.0 × 6.5 cm fluid collection, bowel distention, and indeterminate rectal wall thickening.Exploratory laparotomy revealed extensive dense adhesions, marked visceral and parietal peritoneal thickening, and severe fixation of intra-abdominal structures.Limited adhesiolysis and loop ileostomy were performed.Histopathological examination of tissue submitted as peritoneal thickening demonstrated nonspecific smooth-muscle fibrosis without neoplastic features in the sampled tissue.A distinct encapsulating membrane was not definitively documented, and the rectal abnormality remained incompletely evaluated in the available records.The integrated findings supported a working diagnosis of EPS-like fibroadhesive peritoneal disease.This case illustrates the diagnostic overlap between extensive peritoneal fibrosis and suspected intra-abdominal malignancy, emphasizing the importance of integrating clinical, radiological, operative, and histopathological findings while acknowledging diagnostic limitations.