Collagenous Gastritis Presenting as Chronic Nausea and Vomiting

Collagenous gastritis (CoG) is a rare disorder characterized by subepithelial collagen band deposition in the gastric mucosa. In this report, we describe a case of a 33-year-old woman presenting with chronic, episodic, postprandial nausea and vomiting later found to have biopsy proven CoG. She symptomatically improved following proton pump inhibitor and budesonide initiation and cessation of nonsteroidal anti-inflammatory drugs. This case underscores the insidious nature of CoG; it should be considered in functional or undifferentiated nausea and vomiting. Moreover, it demonstrates associations between CoG, nonsteroidal anti-inflammatory drug use, and isolated immunoglobulin A deficiency.