Symptomatic patients typically present as middle-aged adults with renal colic, kidney stones, nephrocalcinosis and/or recurrent urinary tract infections; however, MSK also may affect children very rarely.

[3] Complications associated with medullary sponge kidney include the following: In recent studies, insight has been obtained on the genetic basis of this disease, supporting the hypothesis that MSK is due to a disruption at the 'ureteric bud-metanephric mesenchyme' interface.

[5] It was previously believed that most cases of medullary sponge kidney were sporadic; however, recent studies show familial clustering of MSK is common and has an autosomal dominant inheritance, a reduced penetrance, and variable expressivity.

[6][7] Other theories suggest that dilatation of a collecting duct may occur, caused by occlusion by uric acid during fetal life or resulting from tubular obstruction due to calcium oxalate calculi secondary to infantile hypercalciuria.

[4] Classically, MSK is seen as hyperechoic papillae with clusters of small stones on ultrasound examination of the kidney or with an abdominal x-ray.

However, IV urography has been largely replaced by contrast-enhanced, high-resolution helical CT with digital reconstruction.

[8] In such cases, treatment may consist of maintaining adequate fluid intake, with the goal of decreasing the risk of developing kidney stones (nephrolithiasis).