Feline Lower Urinary Tract Disease (FLUTD)

Dear Dr. Jody: Our 5-year old indoor cat, “Larry”, was at the emergency clinic over the weekend because of a urinary tract obstruction. The veterinarian recommended that we put him on a special diet to prevent this problem from happening again. The special diet is more expensive than his original food. Is it really necessary to make the switch? 

Feline lower urinary tract disease (FLUTD) is an all too common disorder of cats. The term refers to a broad range of symptoms that can include stones, crystals, tumors, infections, or other inflammation of the lower urinary tract. When the bladder is inflamed, regardless of the cause, the urethra (the tiny little tube that drains the bladder into the litterbox during urination) is at risk for becoming obstructed. An inflamed bladder can produce blood clots, strands of mucus, or an accumulation of crystals that can dam up the urethra when the cat tries to urinate. If the urethra becomes blocked, the cat is physically unable to urinate. Male cats are far more prone to urinary tract obstruction than females because the tip of their urethra is extremely narrow; about the same diameter as the sharp tip of a pin. 

A blocked urethra is a life-threatening emergency. You can imagine how excruciatingly painful it would be to be unable to empty your bladder even though it continues to fill up. An affected cat may often make frequent, minimally productive trips to the litterbox, and his owner may believe he is constipated. The cat may spend excessive time licking his private parts, and he may be moaning or yowling while straining to urinate. Some cats may vomit or be unwilling to eat. 

An emergency visit to the veterinarian is your only chance of correcting your cat’s painful condition. Left untreated, it will result in death of the cat within 48-72 hours. Your veterinarian will need to anesthetize your cat in order to relieve the obstruction. Bloodwork and x-rays are indicated to ensure the kidneys have survived the ordeal and that there are no bladder stones contributing to the symptoms. Your cat will require hospitalization with IV fluids and an indwelling urinary catheter for several days in order to have the best chance at long term survival. Medications may be required, and a diet change is mandatory. 

It has been shown that the cat’s diet plays a major role in the development of FLUTD and urinary tract blockages. The urine chemistry, especially its concentration and its pH (measure of acidity) dictates whether the cat will be prone to FLUTD or not. Ideally, feline urine should be slightly dilute and acidic, with a pH near 6. Cats with urine pH above 6 are more likely to develop stones and urinary crystals, which are microscopic mineral shards that can irritate the bladder wall. 

Choosing a diet that is specifically developed to produce less concentrated and more acidic urine has been shown to reduce the risk of bladder inflammation due to crystals. Selecting an appropriate prescription diet is a critical part of post-obstruction management of a cat with FLUTD. Please contact your veterinarian for more information on diet options that can help minimize your tomcat’s risk of urinary tract disease.