Collagenous gastritis: a case report and review.

In this article, we report a case of collagenous gastritis in a child and review the paediatric cases reported to date. Collagenous gastritis is a rare entity, with only less than 30 cases reported so far, including 12 children, since the first description of this entity by Colletti and Trainer in 1989. This is a histological diagnosis characterised by a dramatically thickened subepithelial collagen band in the gastric mucosa associated with an inflammatory infiltrate. Children with this condition often present with epigastric pain and severe anaemia, with no evidence of extragastric involvement, in contrast to the adult patients, where chronic watery diarrhoea is the main presentation due to associated collagenous colitis. A macroscopic pattern of gastritis with nodularity of gastric mucosa, erythema and erosions are characteristic endoscopic findings in paediatric patients. Specific therapy has not been established and resolution of the abnormalities, either endoscopic or histological, has not been documented. In conclusion, collagenous gastritis is a rare entity of unknown aetiology, pathogenesis and prognosis. Gastroenterologists and pathologists need to be aware of this condition when evaluating a child with epigastric pain, anaemia and upper gastrointestinal bleeding, particularly when endoscopy reveals the nodularity of gastric mucosa. The identification, reporting and long-term follow-up of cases will shed more light on this puzzling condition.