Parenchymal Diseases of the Kidneys

Radiologic evaluation does not currently play a primary role in the definitive diagnosis of diseases of the kidney. Specific diagnosis is based upon clinical pattern, laboratory findings, and renal biopsy. Imaging techniques are ancillary procedures used to detect anatomy, assess function, and evaluate for complications or associated abnormalities. The combination of excellent anatomic delineation and information regarding functional status provided by urography, retrograde pyelography, nuclear medical examinations, ultrasound, computed tomography, magnetic resonance imaging, and angiography does not provide results distinctive enough to allow definitive diagnosis. There is significant overlap of findings on any given examination so that even the most specific pattern, i.e., the microaneurysms seen on renal angiograms in polyarteritis nodosa, is also seen in several other entities, such as systemic lupus erythematosus (SLE) and intravenous drug abuse (Longstretch et al. 1974; Halpern 1971; Lignelli and Buchheti 1971).