Intracranial Lesion in a Patient With Chronic Myeloid Leukemia.

Central nervous system (CNS) histoplasmosis is a rare but serious manifestation of Histoplasma capsulatum infection that often mimics other intracranial pathologies. We report the case of a 22-year-old man with untreated cancer who presented with progressive neurological deficits. Neuroimaging revealed multifocal ring-enhancing lesions, raising the possibility of a broad differential diagnosis including leukemic infiltration and other CNS infections. Extensive evaluation including cultures and molecular assays were negative. Diagnosis was confirmed by a positive urine Histoplasma antigen and identification of fungus from brain tissue biopsy specimens. Targeted antifungal therapy led to complete clinical and radiological resolution, with sustained remission during 3 years of follow-up.