Clinical and Pathological Aspects of Cystic Disease of the Renal Medulla

Abstract

Records of nine cases of this disorder have been published under various titles and data concerning an additional nine cases have been made available to the author. The condition is characterized by the insidious onset of anemia or of severe urinary salt-wasting. Azotemia is found often in the absence of proteinuria or of an abnormal urinary sediment. Arterial blood pressure is usually normal. Osteitis fibrosa is common in younger patients. Parathyroid and adrenal cortical hyperplasia are common at necropsy together with bone and bone marrow changes. The kidneys which are generally somewhat small, are usually of equal size. The subcortical area is occupied by multiple small cysts and the medullary substance completely disorganized. Remaining glomeruli are generally normal or hypertrophied. The pathologic anatomy, which is illustrated by photomicrographs, affords a ready explanation for the pathophysiology of the disorder. The condition is presumed to be a developmental defect of unknown pathogenesis. It has been confused in the literature with "sponge kidney" to which it bears no clinical or pathological resemblance. Treatment is limited to correction of salt depletion, acidosis and anemia.