A 15-year-old, previously healthy boy without a history of smoking or drug abuse, admitted to the hospital with acute epigastric pain without dyspnea or heartburn. On physical examination the boy was pale with tachycardia (110/min), but normal blood pressure (110/70 mmHg) and normal capillary oxygen saturation in room air (SPO2 99%). Tenderness in the upper abdomen was present. Laboratory investigations showed mild iron deficiency anemia (haemoglobin concentration 7.1 mmol/l, mean cellular volume 65 fl, serum iron 4 mmol/l, serum ferritin 3 g/l) with normal infection parameters. X-ray revealed free air under the right diaphragm. Abdominal ultrasound and CT scan were performed in search of underlying abnormalities, but none could be detected. At laparotomy, gastric perforation was found, which was repaired after refreshing the margins and tissue was sent for histopathology. Histopathology of the fragments showed ulceration without demonstrable Helicobacter pylori; recognizable mucosa was lacking. Subsequent gastro-duodenoscopy showed macroscopically a nodular aspect of the corpus with remarkably coarse gastric folds and pseudo-polyps (Fig. 1). Histological examination of gastric biopsies showed active chronic inflammation with lympho-plasma-cellular infiltration and a thickened sub-epithelial collagenous band, up to 23 mum, consistent with the diagnosis collagenous gastritis; the duodenal mucosa was normal.
The patient was treated with iron supplementation because of persistent anemia. Repeated gastroscopies over the years yielded similar results with collagen bands of up to 22-29 m (Fig. 2,3); colonoscopy revealed normal colonic mucosa, both macroscopically and on histological examination. At the age of 18 year, the patient is asymptomatic, but needed frequent courses of iron replacement therapy.