This is the first case to be reported of collagenous gastritis with an underlying history of systemic lupus erythromatosis. The patient’s clinical presentation was probably consistent with type 1 disease with anemia but with no associated colonic involvement, although at her age, it is more common to have type 2 disease with an associated collagenous colitis. Due to the frequent association with immune-related disorders, including celiac disease, collagenous colitis, inflammatory bowel disease and a variety of systemic autoimmune disease, collectively these associations support the hypothesis that collagenous gastroenteritides have an immune activation, including the overexpression of HLA-DR by epithelial cells and CD25-positive cells in the lamina propria seen in the gastric biopsy [
5]. Those activated immune cells produce cytokines and growth factors that stimulate the production of the extracellular matrix leading to collagen deposition. Collagenous gastritis usually presents with anemia from upper gastrointestinal bleeding and epigastric pain [
6]. On endoscopy, the involved mucosa appears thickened and nodular with a diffuse cobblestone appearance. In the stomach the nodularity mainly involves the gastric body, but it is not seen in all cases [
7]. Other reported findings include gastric mucosal erythema, erosions, hemorrhages, ulcerations and exudates [
1]. The diagnosis of collagenous gastritis is made by histology, which shows distinctive findings. The etiology of collagenous gastritis is unclear. In general, it is considered a chronic persistent histologic disease characterized by a chronic intermittent clinical course in the majority of adult patients [
8]. There is no significant mortality risk or periods of severe deterioration [
8]. Collagen thickness has been associated with disease duration but not with disease severity. There have been no reports of carcinoma, lymphoma, or definitive dysplasia developing in association with collagenous gastritis [
9]. There are no established treatment protocols for collagenous gastroenteritides, including collagenous gastritis, and resolution of the abnormalities either endoscopic or histologic has not been documented. Various therapies have been tried for collagenous gastritis including corticosteroids, ranitidine, omeprazole, misoprostol, sucralfate, aminosalicylates, sulfasalazine, cholysteramine and a hypoallergenic diet with marginal results [
2,
6,
7,
10].