Feline Lower Urinary Tract Disease (FLUTD) is a disorder of the bladder and urethra that causes signs including straining to urinate, bloody urine, and at times a complete inability to urinate, which if untreated can lead to kidney failure and death.
The disease is causes by microscopic crystals that form in the urine. These crystals are made from a mineral that goes by various names including struvite, triple phosphate, and magnesium ammonium phosphate. It is unknown why these crystals form in some cats. Urinary tract infections play a role in some cases, but the majority are sterile. Because it is more common in some breeds, a genetic predisposition is suspected. Diet is another factor, though most modern cat foods are formulated to prevent crystals from forming. The disease also seems to be more common in cats with anxiety.
The most common signalment is a young, male, overweight cat, although any cat may be affected.
Struvite crystals are very sharp, and after they form in the bladder they create microscopic lacerations in the urethra as the they pass out of the body. This causes pain, swelling, inflammation, and spasm of the muscle in the urethra. The lumen of the urethra narrows, and it becomes harder to pass more urine. Eventually a plug of mucus and crystals can form. This prevents the bladder from emptying, leading to kidney failure. (acute renal failure).
Treatment includes passing a catheter up the urethra into the bladder, and leaving it in place for some time time allow the bladder to empty and recover its strength. Cats are also treated with intravenous (IV) fluids, to help the kidneys recover and correct electrolyte imbalances. Prognosis is good if the disease is caught in time.
Most cats go home from the hospital with phenoxybenzamine or prazosin, medicines which relax the urethra and make it easier to urinate. Many cats are also treated with antibiotics.
The disease can recur, and long term treatment includes feeding a prescription diet. These acidify the urine more than over-the-counter foods, and they are low in magnesium. They are laboratory tested for FLUTD, safe, and effective. Examples of prescription diets are Purina UR, Hills c/d, and Royal Canin SO.
A new approach to FLUTD is a diet called Hills c/d Stress. This is similar to c/d but contains added ingredients to manage stress, including tryptophan.
Cats with multiple recurrences may need a surgery called a perineal urethrostomy. This usually solves the problem but is reserved for difficult cases due to the pain and recovery time involved.
For more information or if you believe your cat may have FLUTD, please call us.
Evesham Veterinary Clinic
Marlton, NJ 08053