Adrenal Cortical Adenoma with Histoplasmosis in an Immunocompetent Host – An Incidental Discovery

Adrenal involvement in histoplasmosis is typically associated with disseminated infection in immunocompromised individuals. Isolated adrenal histoplasmosis in immunocompetent hosts is rare and frequently mimics neoplastic pathology. A 47-year-old immunocompetent male presented with an incidentally discovered 7 cm left adrenal mass. Hormonal evaluation was unremarkable. He underwent robotic adrenalectomy with cholecystectomy for concurrent gallstones. Gross pathology revealed a well-encapsulated adrenal mass with necrosis. Microscopy demonstrated an adrenocortical adenoma with extensive granulomatous inflammation containing numerous intracellular budding yeasts morphologically consistent with Histoplasma capsulatum. The patient had no systemic symptoms of fungal infection. This case highlights the diagnostic challenge posed by unilateral adrenal histoplasmosis in immunocompetent individuals. Histopathology remains essential for diagnosis, particularly when radiologic and biochemical features suggest an adrenal neoplasm. Awareness of this entity is crucial to avoid misdiagnosis and to guide appropriate postoperative management.