Presumed Congenital Urethrorectal Fistula with Suspected Distal Urethral Atresia in a Kitten Managed with Modified Perineal Urethrostomy: A Case Report

Congenital urethrorectal fistula is exceptionally uncommon in cats and may be difficult to anatomically define when accompanied by distal urethral maldevelopment. A 4-week-old intact male domestic shorthair kitten weighing 745 g was evaluated for watery feces, persistent perianal wetness, and suspected passage of urine through the anus. Manual bladder compression produced dark anal discharge with a creatinine concentration of 1202 µmol/L. Ultrasonography showed a distended, thick-walled bladder and proximal urethral dilation. CT retrograde urethrography demonstrated contrast within the penile urethra, marked dilation of the pelvic urethra, and a blind diverticulum-like pouch, although the fistulous tract was not visualized. The findings supported a presumptive diagnosis of congenital urethrorectal fistula with distal urethral atresia or discontinuity. A modified perineal urethrostomy was performed by anastomosing preserved preputial mucosa to the proximal urethra, establishing urinary diversion without exploring or closing the tract. Urinary outflow and fecal consistency improved, and the upper urinary tract was ultrasonographically unremarkable at postoperative day 25. Stomal stenosis prevented normal urination at day 675 and necessitated a second surgery. At day 995, urination was generally unobstructed, although intermittent urinary leakage and hematuria persisted. In conclusion, combined fluid analysis and multimodal imaging can support recognition of congenital urinary–rectal communication in kittens. Modified perineal urethrostomy can provide urinary diversion when normal outflow cannot be restored, but long-term surveillance is required because leakage and stomal stenosis may occur.