Concurrent Collagenous Gastritis and Collagenous Colitis: A Case Presentation and Review of the Literature.

Collagenous gastritis is a rare gastrointestinal condition, and its presence with collagenous colitis may be an exception. We describe a 31-year-old man with simultaneous collagenous gastritis and collagenous colitis. The patient initially presented with dyspepsia, anemia, and weight loss. Endoscopy assessment revealed irregular gastric atrophy with the normal colon. Gastric biopsies illustrated increased thickness and subepithelial collagen band.