An Apple-core Lesion in the Colon: An Infectious Etiology.

Gastrointestinal involvement occurs in about 70% to 90% of histoplasmosis cases but is usually not the initial manifestation. We present the case of a 52-yearold HIV-positive woman who presented with gastrointestinal symptoms and an apple-core lesion on CT scan of the abdomen. The patient had been diagnosed with histoplasma colitis eight months earlier and was started on long-term itraconazole therapy. However, she prematurely discontinued treatment. A colonoscopy during the present hospitalization revealed a 3.5-cm mass, biopsies of which revealed Histoplasma capsulatum. In the present report, we discuss the differential diagnosis of apple-core lesions in the colon and the importance of keeping histoplasmosis on the differential diagnosis, especially in endemic areas like the Ohio River valley. It is equally important to ensure compliance with treatment of histoplasmosis, as well as close follow-up, as progression to colonic obstruction while on medical management has been reported.