A Complicated “Simple” Renal Cyst

Simple renal cysts are usually asymptomatic and benign. Rarely, symptoms and complications can develop from local mass effect which is illustrated by this case.

77 year old Caucasian male presents with abdominal pain for five days. Abdominal exam was diffusely tender, markedly distended, tympanic with absent bowel sounds. His work-up included an abdominal x-ray showing a colonic obstruction and abdominal CT showing a large 27 cm renal cyst. Drainage of the renal cyst resolved obstructive symptoms.

A simple renal cyst should not be overlooked as the reason for acute abdominal pain. Simple renal cysts, though benign are not without complications.