Silent Megacolon: Fulminant Clostridioides Difficile Infection Without Diarrhea Mimicking Acute Colonic Pseudo-Obstruction

ABSTRACT Clostridioides difficile infection (CDI) typically presents with diarrhea in elderly or antibiotic-exposed patients. We report a 40-year-old immunocompetent man with alcohol use disorder who presented with abdominal pain and jaundice, rapidly progressing to refractory constipation and colonic dilation (14.7 cm) mimicking acute colonic pseudo-obstruction. Conservative management including bowel regimens and neostigmine (generally contraindicated in suspected toxic megacolon) were attempted. Colonoscopic decompression revealed cecal pseudomembranes whereas rest of colon was grossly normal. Stool testing showed discordant results that is, negative toxin enzyme immunoassay but positive stool polymerase chain reaction (Nucleic Acid Amplification Testing), supporting CDI in appropriate clinical context. Despite appropriate broad-spectrum antibiotics and emergent subtotal colectomy for fulminant disease with ischemic changes, he developed septic shock and multiorgan failure. This atypical, fulminant CDI presentation without diarrhea, initially mimicking acute colonic pseudo-obstruction, with isolated cecum and ileum involvement, underscores diagnostic pitfalls and need for early polymerase chain reaction/endoscopy in unexplained megacolon.