A 48–year–old woman in generally good health presented with two months of profuse, large volume watery diarrhea. She was initially diagnosed with Clostridium difficile colitis and symptoms resolved with oral metronidazole. Five days after treatment, she developed nausea and >20 loose watery stools daily including diarrhea when she was not eating, nocturnal diarrhea and fecal incontinence. She had no melena or hematochezia but had a 50 pound weight loss. Extensive inpatient workup was unrevealing and she was transferred for evaluation. The patient denied recent travel or sick contacts. She lived on a farm with goats but denied animal health issues. She had not changed her diet; symptoms did not improve with elimination of dairy or gluten. She had no family history of gastrointestinal or autoimmune disease. The patient was afebrile with normal vitals. Exam was remarkable only for mild diffuse abdominal tenderness without peritoneal signs. White cell count was normal; hematocrit 51. Chemistries and liver tests were normal except for a CO2 of 20. Multiple infectious stool studies were normal. She had 3+ fecal leukocytes. Stool electrolytes were consistent with an osmotic diarrhea. Laxative screening, somatostatin, chromogranin, serum anti–tissue transglutaminase and anti–enterocyte IgG, IgM, and IgA were negative. HIV, hepatitis serologies, and thyroid studies were negative. Esophagogastroduodenoscopy and colonoscopy with biopsy revealed complete flattening of villi throughout with crypt drop–out and areas of fibrosis, severe inflammation with erosions and severe neutrophilic infiltration with numerous crypt apoptotic bodies in the duodenum, terminal ileum, right colon, left colon, and rectum. High dose intravenous steroids for 7 days and multiple antidiarrheal agents as well as parenteral nutrition and bowel rest had no effect. On HD#28, she was started on Inflixamab for treatment of presumed Adult Autoimmune Gastroenteropathy. After 5 days, she had only 2–3 formed stools daily and she tolerated a regular diet. She was discharged to home on HD#35.
Adult autoimmune enteropathy (AE) is a rare cause of severe intractable diarrhea with <25 cases in the literature. The disorder is associated with immune–mediated disruption of the intestinal mucosa and often results in significant weight loss and malnutrition. In a Mayo Clinic series, 87% were Causcasian, 47% female with a median age of 55 years. The majority of patients are predisposed to autoimmune disease. Symptoms are usually not responsive to bowel rest or gluten–free diets. Antienterocyte antibodies have been found but are not pathognomonic. Small bowel biopsy demonstrating villous atrophy is the diagnostic gold standard. Immunosuppressive therapy is required in most cases with clinical improvement in 60% after 1–8 weeks.
Autoimmune Enteropathy remains a rare disorder in adults but should be in the differential of severe protracted diarrhea requiring hospitalization.