medullary sponge kidney
a rare congenital condition characterized by multiple small cystic dilatations of the medullary part of the renal collecting tubules, so that the organ has a spongy, porous feeling and appearance. It is usually asymptomatic, but there may be calculus formation within the cysts, hematuria, renal colic, or recurrent renal infection. Called also Cacchi-Ricci disease and sponge k.
Medical dictionary.
2011.