S4778 A Rare Cause of Gastrointestinal Hemorrhage: Trichuris trichiura Infection

Introduction: Trichuris Trichiura(T. Trichuris) is a common nematode infection globally, especially in tropical regions. While most cases are asymptomatic or present with mild gastrointestinal symptoms such as loose stools, severe manifestations are rare. We report an unusual case of T. trichiura infection presenting as severe gastrointestinal hemorrhage. Case Description/Methods: A 79-year-old Filipino woman residing in Hawai’i with a history of osteoarthritis with recent 3-week use of diclofenac twice daily presented with exertional dyspnea and melena. She reported the onset of dyspnea 3 days prior to admission, accompanied by melena and occasional fresh hematochezia, though she did not routinely inspect her stool. Patient had a travel history to Philippines 3 months prior to the presentation for 3 weeks. Her vital signs were stable on presentation. Laboratory evaluation revealed significant anemia, with hemoglobin decreased to 7.0 g/dL from a baseline of 14.6 g/dL 10 months earlier, requiring transfusion of 2 units of packed red blood cells and a leukocytosis with normal eosinophil count (191/μL). Esophagogastroduodenoscopy advancing to the second portion of the duodenum showed no evidence of bleeding. Subsequent colonoscopy demonstrated patchy non-bleeding granular mucosa in the ascending colon with a worm adherent to the mucosal surface. The terminal ileum appeared normal. Biopsies from the small aphthous appearing ulcer in the ascending colon showed focal active colitis with increased eosinophils and parasitic structures consistent with T. Trichuris infection. Stool oval and parasite test was negative. Patient was discharged after resolution of melena and stabilized hemoglobin level. At follow-up clinic, patient reported no recurrent bleeding, and her hemoglobin almost returned to her baseline. Discussion: Overt gastrointestinal bleeding due to T. Trichiura is exceedingly rare. While stool ova and parasite examination is a standard diagnostic tool, it may yield false negatives, especially in the setting of bowel preparation. Colonoscopy may help in the diagnosis of T. Trichiura infection in patients with negative stool examination. Additionally, peripheral eosinophilia may be absent, as seen in up to 50% of T. trichiura infections which is lower than with other helminths. T. trichiura may cause unexplained gastrointestinal bleeding, particularly in patients from endemic areas.