Renal agenesis is a rare disorder in feline species, commonly associated with reproductive malformation. This study aims to report the case of a cat with unilateral renal agenesis combined with ipsilateral cryptorchidism, emphasizing the diagnosis, treatment and patient follow up. The patient was taken to the Veterinary Hospital of the Federal University of Rio Grande do Sul to evaluate the cryptorchidism. The renal agenesis was an incidental finding during the abdominal ultrasound. At laparotomy, the absence of the right kidney and ureter was confirmed, hypertrophy of the left kidney and the presence of an ectopic testicle were found. The patient was discharged after recovering from anesthesia and remains clinically stable six months after surgery. The unilateral renal agenesis is a life compatible condition as long as the existing kidney has an acceptable performance. Therefore, it is suggested that the chance of a single kidney in cats whit cryptorchidism should be investigated, given the correlation between these malformations, and aiming to monitor renal function throughout the life of the patient.
renal malformation; single kidney; testicle; congenital diseases