Multicystic dysplastic kidney

Overview
Multicystic dysplastic kidney (MCDK) is a condition that results from the malformation of the kidney during fetal development. The kidney consists of irregular cysts of varying sizes and has zero function.

Epidemiology
In the United States, the incidence of MCDK is estimated to be 1 in every 2400 live births.

Diagnosis
MCDK is usually diagnosed by ultrasound examination before birth.

Ultrasonography

 * Mass of non-communicating cysts of variable size.
 * Unlike severe hydronephrosis, in which the largest cystic structure (the renal pelvis) lies in a central location and is surrounded by dilated calices, in multicystic dysplastic kidney the cyst distribution shows no recognizable pattern.
 * Dysplastic, echogenic parenchyma may be visible between the cysts, but no normal renal parenchyma is seen.

Images courtesy of RadsWiki

Treatment
MCDK is not treatable. However, the patient is observed periodically for the first few years during which ultrasounds are generally taken to ensure the healthy kidney is functioning properly and that the unhealthy kidney is not causing adverse effects.