FUS (Feline Urologic Syndrome)

Because feline urologic syndrome (FUS) is a very serious disease that can be fatal to a cat if left untreated, you need to be aware if any of these signs occur in your pet. Most FUS signs result from irritation of the urinary tract. Be suspicious if your cat shows prolonged squatting and straining when urinating, attempts to urinate more frequently than normal, urinates in unusual locations, has a distended, hard bladder that is painful to the touch, or has bloody urine.

FUS can also cause your pet to lose appetite, act sluggish, or begin vomiting, especially if the urine flow is blocked. If brought immediately to your veterinarian, treatment of your pet for FUS can bring prompt recovery. Left untreated, the accumulated poisonous urine wastes can be fatal within 12 to 48 hours.

Urologic Syndrome is an inflammation of the urinary tract (specifically the bladder and urethra) that may slow or stop normal passing of urine. It is responsible for 10% of cat owners' visits to veterinary hospitals.

FUS occurs as frequently in male as female cats. Yet, because of anatomical differences, actual obstruction occurs more often in the male. The disease occurs more in cats that urinate less because of reduced physical activity, and in cats eating foods that contribute to formation of urinary crystals.

High levels of magnesium and an alkaline urine in bladder lead to formation of mineral crystals that develop into bladder stones, irritate the urinary tract lining, and plug the urethra.

The inflammation of FUS is caused by crystals (struvite) in the urine irritating the walls of the lower urinary tract. Many additional interacting factors can contribute to the development of FUS. Two factors of primary importance are a high concentration of the mineral magnesium in the urine and an alkaline (high pH) urine. The increased concentration of magnesium is caused by:

1. High levels of magnesium in diet;
2. Infrequent urination caused by a dirty or not easily reached litter box;
3. Reduced physical activity;
4. Reduced drinking of water caused by unavailable or poor-quality water.

If your cat's urinary tract is blocked, your veterinarian will immediately empty the bladder. Then, the cat will be given a detailed examination to determine the appropriate therapy. Immediate treatment may include fluid therapy to relieve dehydration and re-balance the blood chemistry, removal of any mineral crystals obstructing urine flow, insertion of a urinary catheter, and hospitalization until your cat can urinate normally.

A diet reduced in magnesium which also allows production of a normal acid urine prevent formation of crystals to allow free flow of urine.

Struvite urinary crystals can be dissolved in your cat's bladder and urinary tract by feeding a special diet that is low in magnesium and aids in maintaining a normal acid urine. In cats fed this special diet exclusively, signs associated with FUS will normally cease within the first 10-14 days; and to completely dissolve the struvite crystals, the diet is fed 2-3 months.

At home, care and management include:

1. Providing free access to fresh, clean water;
2. Providing a clean box for each cat;
3. Following your veterinarian's instructions for administering medications and care;
4. Encouraging exercise;
5. Controlling the amount of food eaten if your cat is overweight;
6. Giving no other food or vitamin-mineral supplements while your pet is receiving the special crystal-dissolving diet.