S4546 Beyond IBS: An Unusual Case of Eosinophilic Gastroenteritis

Introduction: Eosinophilic gastroenteritis is a rare form of eosinophilic gastrointestinal disorders (EGID) that occurs in about 6–7/100,000 people. It results from the buildup of eosinophils leading to inflammation and damage to the gastrointestinal (GI) tract. According to Klein’s classification, it can affect the mucosal, muscular and serosal layers. Herein, we present an interesting case of EGID following travel to the Dominican Republic with GI symptoms in the setting of a negative infectious workup, and highlight the utility of steroids in the treatment course. Case Description/Methods: A 23-year-old woman presented to the hospital with abdominal pain, nausea, vomiting, and constipation. These symptoms began 3 weeks after a 5-day trip to the Dominican Republic. On review of her pertinent history, she denied sexual activity and drug use. However, she reported oral intake of uncooked fish and recreational activities such as swimming in the ocean, multiple mosquito bites and use of tap water. On arrival, she was hemodynamically stable. Initial labs showed eosinophilia at 9.23 × 10⁹/L, prompting an extensive infectious workup, primarily targeting Strongyloides, Toxocara, and hookworm. Hematology was consulted and performed an extensive workup, a peripheral blood smear confirmed eosinophilia. Computed tomography (CT) of the abdomen revealed multifocal mucosal thickening and hyperenhancement involving the stomach, small bowel, and colon. Conservative management was started, infectious disease recommended treatment with a dose of oral albendazole 400 mg and ivermectin 200 mcg/kg. She initially improved and was discharged but eventually returned with worsening symptoms. The GI team was consulted due to progression of CT findings and concern for inflammatory bowel syndrome. EGD and colonoscopy were grossly unremarkable, but biopsies showed >50 eosinophils/hpf in the duodenal mucosa, antral mucosa, and colonic mucosa. Given the negative infectious workup, we initiated prednisone 20 mg with a taper over 4 weeks. She experienced symptom relief at outpatient GI follow-up. Discussion: EGID is a rare disorder that presents with symptoms such as nausea, vomiting, and constipation. The literature confirms that eosinophilic infiltration can cause bowel wall thickening, resulting in constipation that may mimic small bowel obstruction. This represents an important functional cause of obstruction. We highlight how corticosteroids can be beneficial after completing a hematology-oncology workup and ruling out infectious causes.