2590 Autoimmune Enteropathy: A Rare Cause of Chronic Diarrhea

Abstract

INTRODUCTION: Autoimmune enteropathy (AIE) is a rare condition that may be easily missed without careful review of the patient's history and laboratory values. It is characterized by intractable diarrhea, malabsorption, abdominal pain, and anorexia. CASE DESCRIPTION/METHODS: A 74-year-old female with history of hypertension presented with 5 weeks of persistent nausea, vomiting, and diarrhea. These symptoms occurred while traveling. She denied consumption of unusual foods, drinking water from lakes, or fevers. Following her trip, she went to Boston. There, she had 8 non-bloody, watery bowel movements. She also noted abdominal distention and pain. She was given a 5-day course of ciprofloxacin without improvement. Once home, she presented again with weakness and dehydration. Infectious stool studies proved negative. She was treated with supportive care once again. On follow up, she was noted to have an 8-pound weight loss. She continued to have persistent diarrhea, leading to presentation to her third hospital. Repeat stool studies were positive for rotavirus. CT was consistent with enterocolitis. Labs were notable for fecal calprotectin 934, hypoalbuminemia 1.5 g/dL, and elevated CRP (44.2 mg/L). The patient underwent upper endoscopy and colonoscopy. Findings included diffuse granular mucosa with flattened villi in the gastric antrum, duodenum, and terminal ileum. Pathology revealed patchy chronic enteritis with crypt loss. The patient was started on IV solumedrol with improvement in symptoms. She was discharged on a prednisone taper for autoimmune enteritis. DISCUSSION: AIE is a rare disease among adults. AIE is diagnosed histologically by villous atrophy of the small intestine, as seen in our patient. The significance of anti-enterocyte and anti-goblet cell antibodies in AIE is unclear. A recent case series has shown no association between the clinical course and the type of gut epithelial cell antibodies. Treatment of AIE continues to evolve. Steroids are typically first used in order to control active disease. However, steroid-sparing therapies are preferred for long-term maintenance as this is a disease that typically requires ongoing immunosuppression. Use of TNF alpha-inhibitors has been trialed in a small number of patients. A recent case study studied the use of vedolizumab, an integrin-binding antibody, on a patient with good response. Overall, more cases are needed in order to improve understanding of AIE and to discover improved therapies for this rare disease.