2760 A Case of Collagenous Gastritis: A Rare Entity

Abstract

INTRODUCTION: Collagenous gastritis (CG) is a rare histopathologic entity that involves marked subepithelial collagen deposition in the gastric mucosa. Endoscopic findings can be diverse such as mucosal erythema, nodularity and ulceration. The presentation is very diverse such as abdominal pain, weight loss, gastrointestinal bleeding and dyspepsia. Its treatment remains unclear. CASE DESCRIPTION/METHODS: 71-year-old with long history of dyspepsia was referred to our institution due to a 6-month history of epigastric discomfort, profound weight loss (50 lb) and early satiety. Symptoms were mildly improved with sucralfate and smaller and more frequent meals. Tissue transglutaminase antibody was negative. Endoscopy at other institution suggested collagenous gastritis but biopsies were not conclusive. Endoscopic ultrasound at our institution was done for further characterization of the stomach layers and revealed a tubular J-shape stomach deformity with diffuse atrophic mucosa in the gastric body. Localized submucosal wall thickening was visualized endosonographically in the entire body of the stomach which measure up to 5 mm in thickness in the gastric wall. Random gastric biopsies could not confirm CG diagnosis. Persistent symptoms led to further work up including MRI enterography and gastric emptying study, all negative. Eight months later, “well type” biopsies were taken from the gastric body and antrum. Pathology report revealed antral glands atrophy with pyloric hyperplasia, prominent smooth muscle hyperplasia in the lamina propia, along with gastric corpus and antrum with thickened subepithelial collagen layer on hematoxylin and eosin, confirmed on trichrome stain. These features were consistent with a diagnosis of collagenous gastritis. Although limited evidence on the treatment of this disease, patient was started on budesonide therapy (9 mg/day). Future endoscopic surveillance and clinical follow up is planned to assess symptomatic improvement. DISCUSSION: Collagenous gastritis is a rare entity as only 60 cases have been reported in the literature. We need more awareness of this disease for early recognition and reduction of unnecessary work up. Clinical presentation is very diverse and endoscopic findings can be very subtle. High clinical suspicion is necessary to allow proper biopsy techniques. The well technique permits deep tissue sampling by taking multiple samples from the same site and has been advocated for use in subepithelial lesions, avoiding the need for full thickness biopsy or surgery.