A case of intrarenal benign cystic teratoma.

A 6 year-old boy was diagnosed with infected renal cysts that were removed in pieces. Cytological examination of purulent fluid from the cysts during surgery contained a few isolated keratinizing aquamous cells and hair shafts with inflammatory background. Intrarenal cystic teratoma is very rare. Differential diagnosis of intrarenal cysts is paramount, especially in children, to ensure the correct choice of therapy. In our case, we found cytologic examination duning surgery to be useful in dianosis.