Partial urethral duplication in a cat

A 3-year-old neutered male domestic shorthair cat with a history of urethral obstruction was evaluated at a veterinary referral center for acute onset of hunched posture and signs of discomfort on being handled. No evidence of urethral obstruction was found; signs initially responded to medical management, but the cat was presented to the primary care veterinarian < 48 hours after the initial examination with signs suggesting urethral obstruction.

No urinary calculi were detected radiographically. Attempted urinary catheter placement was unsuccessful, and the cat was returned to the referral center for evaluation and treatment of suspected urethral obstruction. Hematologic evaluation revealed hyperglobulinemia and leukocytosis; the cat was febrile, its prepuce was swollen, and its urinary bladder was soft but could not be manually expressed.

A urinary catheter was placed; urinalysis revealed hematuria, leukocyturia, and bacteriuria. Medical management included analgesic, antimicrobial, urethral antispasmodic, and IV fluid treatment. Positive-contrast cystourethrography results were equivocal for a congenital anomaly versus urethral rupture. Contrast-enhanced CT revealed a sinus communicating with the dorsal aspect of the urethra, and urethral rupture was ruled out. Partial urethral duplication was confirmed surgically; perineal urethrostomy was performed, creating an opening to the accessory urethra, and the strictured orthotopic urethra was ligated. Four weeks after surgery, the cat was doing well.

This case highlighted the importance of advanced imaging to distinguish between urethral rupture and a congenital malformation in a cat with signs of lower urinary tract disease. This approach was pivotal to appropriate diagnosis and management and a favorable outcome for the patient.