Treatment of urethral obstruction secondary to caudal bladder displacement, trigonal invagination, and urethral kinking in a dog.

CASE DESCRIPTION A 15-year-old spayed female mixed-breed dog was evaluated for a 7-week history of stranguria, pollakiuria, and intermittent urethral obstruction. CLINICAL FINDINGS On initial evaluation, the patient had persistent stranguria with lack of urine production; after multiple unsuccessful attempts to urinate, a large volume of urine was produced. Prior to voiding the large volume, the urinary bladder was not palpable during examination. Abdominal ultrasonography confirmed caudal displacement of the urinary bladder, and the urethra and trigone could not be located ultrasonographically. Positive-contrast cystourethrography and CT confirmed caudal displacement of the urinary bladder and also revealed trigonal invagination and urethral kinking; dysuria was attributed to these findings. TREATMENT AND OUTCOME Surgical repositioning of the lower urinary tract was performed. The urinary bladder was moved cranially and was fixed in place along the left lateral aspect of the body wall by cystopexy. After surgery, positive-contrast cystourethrography revealed a more cranial positioning of the urinary bladder and straightening of the urethra with no urethral kinking or trigonal invagination. Immediately after surgery, stranguria had resolved and the patient was able to void normally. Two years after surgery, the dog was reported to be urinating normally. CLINICAL RELEVANCE Surgical correction of caudal urinary bladder displacement with cystopexy led to resolution of trigonal invagination, urethral kinking, and urethral obstruction in the dog of the present report. Trigonal invagination and urethral kinking, although uncommon findings, should be considered as possible causes of dysuria in dogs.