Suspected congenital urethral diverticulum in a dog.

A 2-year-old neutered male dog with a history of urinary incontinence, recurrent urinary tract infections, and unilateral cryptorchidism was presented with an acute onset of perineal swelling. Urinary contrast studies revealed a urothelial lined structure in the perineum. Surgical resection of 80% to 90% of this structure, suspected to be a congenital urethral diverticulum, was successful.