This specimen represents one-half of a kidney grossly enlarged by multiple cysts up to 3 cm. in
diameter. The general form of the kidney is retained, while the external surface is distorted by a
multitude of thin-walled cysts. The majority of the cysts contain clear fluid, although some contain
blood. Approximately 1/3 of patients with this condition have cysts in the
liver and there is also a clinically significant association with aneurysm of the cerebral arteries.