Intestinal obstruction and peritonitis resulting from gastrointestinal histoplasmosis in an AIDS patient

Gastrointestinal histoplasmosis complicated by intestinal obstruction and peritonitis has not been reported. We report a case of gastrointestinal histoplasmosis in a 27-year-old patient with acquired immunodeficiency syndrome (AIDS). The patient was a Chinese man from Thailand with a history of intravenous drug use and unprotected sex with female prostitutes. He was admitted for prolonged fever, abdominal pain, and diarrhea. Colonoscopy revealed volcano-like ulcers and tumors, while computed tomography of the abdomen showed a colon tumor and hypoattenuated lymphadenopathy of the retroperitoneum. Histopathologic examination as well as cultures of colon biopsy specimens and an aspirate from the retroperitoneal lymphadenopathy revealed Histoplasma capsulatum. Intestinal obstruction and peritonitis requiring surgical intervention developed, despite amphotericin B therapy. Histoplasmosis should be included in the differential diagnosis in AIDS patients who present with colon tumors, retroperitoneal lymphadenopathy, and peritonitis.