Feline Lower Urinary Tract Disease (FLUTD) is commonly diagnosed in young to middle aged, overweight, male desexed, cats. The diameter of the urinary tract at the level of the penis is very small and is prone to blockage with urinary crystals, sediment and also due to spasm of the muscles of the lower urinary tract. In male cats there are several factors thought to be responsible, such as urinary crystals or stones, infection (cystitis), or behavioural and stress. Urinary tract blockage can also occur in male dogs due to bladder stones, trauma or tumours, and is less commonly seen in females. Obstruction will prevent the patient from urinating and cause excess accumulation of urine in the bladder, making the patient very ill due to a build-up of toxins and electrolyte imbalances.
Urgent veterinary attention is required in these situations to relieve the bladder and correct the electrolyte imbalances. Once these are stabilised the patient may either be managed medically with a combination of dietary control, or surgically to bypass the obstructed urinary tract or widening the urinary tract opening to reduce the risk of future blockages.
A urethrostomy is used to bypass the urinary tract blockage and widening the urinary tract opening to reduce the risk of future blockages in patients where repeat episodes of obstruction have occurred. In cats a perineal urethrostomy effectively removes the penis at the level where the urinary tract is wide enough to minimise the risk of blockage. In male dogs the preferable procedure is called a scrotal urethrostomy, where the urinary tract opening is located near the scrotum, bypassing the penis completely. The final outcome means that 'he', will pee like a 'she'.
Complications associated with surgery are immediate post-operative swelling, bleeding, wound opening with urine leakage, and scar tissue formation (stricture), and are reported in up to 25% of cases. Management of post-surgery swelling requires the use of a urinary catheter until the swelling resolves and the patient can urinate normally. Scar formation usually can occur at any stage in the weeks to months following surgery and may require repeat surgery to relieve the scar. Leakage of urine should be identified early, and additional sutures placed to close the leak. Bleeding may occur during or following urination for 1-3 weeks after surgery, but this should resolve gradually without intervention. Urinary or faecal incontinence has been reported but is rare. Longer term complications include bladder infection (cystitis) in 10-50% of cases, which are treated with antibiotics, and late scar formation.
The prognosis as reported by owners following surgery is good in the majority of patients who have urethrostomy for the management of lower urinary tract obstruction.