Perinephric extravasation of urine with pseudocyst formation in a cat

A case of unilateral perinephric pseudocyst formation as a result of extravasation of urine is reported. The main presenting signs and the initial clinical examination did not directly indicate severe renal involvement. The subsequent development of pseudocysts as a result of chronic extravasation of urine was positively diagnosed by laboratory investigations and ancillary procedures. Treatment consisted of surgical removal of the affected kidney.