Autosomal Dominant Polycystic Kidney Disease (ADPCK):

Sonography of this 55 yr. old male patient, who presented with hematuria, reveal bilateral grossly enlarged kidneys (14 to 16 cms. in length, 8 to 10 cms. width). The kidneys are replaced by multiple large cysts (more than 2 in each kidney) of sizes varying from 2 to 5 cms. (Criteria for diagnosis of ADPCK: a) more than 2 renal cysts in one/ both kidneys, if age less than 30 yrs. b) 2 or more cysts in each kidney, if aged from 30 to 59 yrs. c) 4 cysts in each kidney if aged more than 60 yrs.) There is very little normal renal parenchyma seen in these images. Note that the cysts are non-communicating ruling out hydronephrosis. The right kidney shows an echogenic focus, in one cyst, which may be a calculus or calcification. A solitary cyst is seen in the right lobe of liver. These ultrasound images are diagnostic of Autosomal Dominant Polycystic Kidney (ADPCK) disease.      

References:

1) http://en.wikipedia.org/wiki/Polycystic_kidney_disease (free article)

2) http://www.emedicine.com/med/topic1862.htm (free article)