AbstractA case of extensive unilateral renal aspergillosis in a man with hairy cell leukemia is described. This case report is unique because of the long duration of the infection that is more characteristic of patients without malignancy. The degree of unilateral renal involvement found, which included invasion of kidney parenchyma, is uncommon in patients with malignancy. Such patients typically have diffuse disseminated disease with microabscesses. The literature on urinary tract aspergillosis in patients with and without underlying malignancy is reviewed