Collagenous Gastritis in a Patient Treated with Venlaflaxine

Abstract

Purpose: Collagenous colitis, subtype of microscopic colitis, is a diagnosis made via assessment of typically normal appearing colonic mucosa biopsies. Collagen deposition is seen in the sub-epithelial layer. Symptoms include loose, watery diarrhea; abdominal pain; weight loss; and dehydration. Although collagenous colitis is a well-known entity, etiology is still unknown with medications as possible triggers. Successful treatment and symptom resolution has been shown with corticosteroids, specifically budesonide. Case reports have documented the spread of collagenous colitis to the small bowel, however, extent to gastric mucosa is extremely rare. A 62-year-old Caucasian female presented to clinic for chronic diarrhea and moderate epigastric cramping for the past 3 months. Patient's medical history included anxiety and depression treated with venlafaxine that was started 7 months prior to presentation. Patient described the diarrhea as watery with mucus, non-bloody and occurring up to 30 times per day with intermittent epigastric discomfort. No other symptoms were reported and weight loss was not experienced. Patient denied any recent illness, antibiotic use, sick contacts or travel. Treatment with over the counter anti-diarrheal medications and prescribed oral ciprofloxacin were unsuccessful. An extensive investigation that included routine blood tests, serologic markers, stool studies, urine collection were within normal limits. An EGD and colonoscopy were performed with biopsies taken from normal appearing stomach, small and large intestine, and rectal mucosa. Samples taken from the ascending, transverse and sigmoid colon along with the rectum showed collagen deposition compatible with collagenous colitis. Surprisingly, gastric antrum samples also showed collagen deposition. The patient was treated with an oral course of budesonide, which resolved symptoms 2 weeks after initiation. Although collagenous colitis symptoms, complications and treatment options are widely reported, collagenous gastritis appears to be a rare entity. To our knowledge, few cases of collagenous gastritis have been reported in adults and children with young women being the major group associated with the disease. Even less data is available on treatment with few reported successes with corticosteroid therapy. Possible trippers include anti-depressants such as venlafaxine in our patient. Clinicians should be cognizant of collagenous gastritis to be a cause of symptoms in patients with epigastric pain or discomfort with diffuse watery diarrhea. A thorough colonoscopy and EGD with multiple biopsies of normal appearing mucosa is justified in these patients and close follow-up is mandatory as relapse of the disease state may recur.