Gastrointestinal histoplasmosis.

Three cases are reported of gastrointestinal histoplasmosis in patients who came from the Caribbean or South America and had lymphoma, acquired immunodeficiency syndrome, and prior local radiation therapy. The patients had small-bowel obstruction with ileal involvement, mucosal erythema, and friability on colonoscopy with colonic involvement and an exophytic rectal mass with rectal involvement. Review of the 77 reported cases of gastrointestinal histoplasmosis shows that this is a clinical subset of disseminated histoplasmosis. With gastrointestinal involvement, pulmonary symptoms are uncommon and gastrointestinal symptoms predominate. Fever is less common than in other forms of dissemination. The most common lesions are a mass or ulcers, which often mimic inflammatory bowel disease or carcinoma. Terminal ileal involvement predominates in one third. The complement fixation test was positive in about three quarters of cases tested, but the skin test is not diagnostically useful. In one quarter of patients there is other evidence of immunosuppression. In the immunosuppressed, gastrointestinal histoplasmosis must be considered, even in a patient from a nonendemic area, who presents with lesions appearing like carcinoma or inflammatory bowel disease. When feasible, endoscopic examination and biopsy with stains and culture for histoplasmosis is recommended for diagnosis. Medical management is recommended, with surgery reserved for acute emergencies or when mandatory for diagnosis.