Simple renal cysts are common renal lesions (70%); the majority are benign, and further imaging is not required.
The most common form of cystic renal disease is due to autosomal dominant polycystic kidney disease (PKD) and accounts for 8%-10% of all causes of end-stage renal disease. The develoment of renal cysts has also been associated with diuretic use as well as some medications.
The presentation of renal cysts varies based on the cause, and physical examination may reveal a palpable flank or abdominal mass. Radiographic findings of a thick irregular wall, thick septations, or multilocular findings are concerning for malignancy.
N28.1 – Cyst of kidney, acquired
Q61.00 – Congenital renal cyst, unspecified
722223000 – Cyst of kidney
- Developmental – Multicystic dysplastic kidney, uniformly diagnosed on prenatal ultrasound; medullary sponge kidney
- Genetic – Autosomal dominant PKD, autosomal recessive PKD, medullary cystic kidney disease, glomerulocystic kidney disease, and juvenile nephronophthisis
- Associated with systemic disease – von Hippel-Lindau syndrome and tuberous sclerosis
- Acquired – Simple cysts, acquired cystic renal disease, lithium-induced renal disease (microcysts in the medulla and cortex), angiomyolipoma, metanephric adenoma, cystic oncocytoma
- Malignancy-associated – Cystic renal cell carcinoma, lymphoma