Ureteral obstructions in cats and the use of Subcutaneous Ureteral Bypass (SUB)

Urethral obstructions in cats and the subcutaneous urethral bypass device

Urethral obstructions are increasing in frequency with cats. In normal cats, kidneys produce urine that flows through the ureter into the bladder and out through the urethra. Cats seem to produce calcium oxalate stones, which can cause complete or partial obstructions in the ureter. Some cats may not show immediate symptoms, and the obstruction may go unnoticed. Damage to the inside of the kidney can occur, leading to changes in kidney function.

Diagnosis involves blood and urine testing, as well as imaging such as x-rays and ultrasound. Calcium oxalate stones can be visible on x-rays, and ultrasound helps evaluate kidney size and dilation in the renal pelvis. A dye test may also be used to identify obstructions. If an obstruction is confirmed, a subcutaneous urethral bypass device may be recommended. You may like to view the video by Dr. Peter Delissa detailing the surgical placement of these devices. The implanted device runs from the kidney to the body wall, allowing urine to bypass the obstruction. Regular flushing and a wet food diet are crucial for device maintenance.

Complications, including a higher risk in cats with pre-existing urinary tract infections, can occur. Regular monitoring and culturing the cat's urine are essential. Potential complications include blood clots, which may require flushing with a special drug. This procedure is life-saving but not without risks. If you suspect a urethral obstruction, contact your vet or CSS for prompt evaluation.