Partial, combined cortical and medullary nephrocalcinosis: US and CT patterns in AIDS-associated MAI infection.

An unusual pattern of nephrocalcinosis associated with Mycobacterium avium-intracellulare infection and asymmetrically involving the renal cortex and medulla in a patient with acquired immunodeficiency syndrome (AIDS) is reported. This pattern, "partial nephrocalcinosis," differs from the increased parenchymal echogenicity seen on ultrasound and the parenchymal calcification noted on computed tomography that result from other causes. Partial nephrocalcinosis should suggest an infection such as one caused by M. avium-intracellulare.