A recurring problem in male cats today is the incidence of urinary blockage.  This occurs when a cat is unable to pass urine through the urethra, the tube from the bladder to the genitalia, caused by a crystalline stone or protein plug.  This is a life-threatening problem, which, if not treated will cause death.  It is a condition that all cat owners should be aware of in order to protect their pets.

Although the problem is seen in all cats, females rarely become blocked because their urethra is wider, allowing stones and plugs to pass more easily.  Male cats have a narrower urethra, and therefore are more prone to having a blockage.  More common than the plugs, stones are to blame for most blockages.  These stones are made from a mass of crystals which can be formed in the bladder and then become lodged in the urethra.

One way to help decrease the risk of urinary blockage in your cat is to feed him a high quality, premium cat food that you purchase from a pet store.  These foods have been put through feeding trials and guarantee consistent, balanced nutrition for your cat.  Most of the foods bought at the grocery store are not as researched and therefore, may not be giving your cat what he really needs.

Normal cat urine is slightly acidic, having a pH of around 7.0 or lower.  If a cat's urine becomes highly acidic or highly alkaline, the risk of crystal production and stone formation is high.  The two most common kinds of crystals seen in cats are struvite (seen in alkaline urine) and calcium oxalate (seen in acidic urine).

Early signs of lower urinary tract disease that may lead to blockage include:

• A litter-trained cat that suddenly starts urinating outside of the litter box.
• Urinating small amounts frequently.
• Blood in the urine.
• Lethargy and decreased appetite and/or increased drinking.
• Excessive licking of genitals.
• Straining in the litter box to urinate (Note: Many owners confuse this with constipation and do not realize the urgency of taking their pet to the hospital).

A cat should be taken to the veterinarian as soon as possible with any of the above symptoms.  If the problem is severe and the urethra becomes blocked, the symptoms you may see include vomiting, depression, loss of appetite, dehydration, and a urine odor from the mouth.  When the urethra becomes blocked, time is of the essence.  When a cat cannot urinate, coma and death follow in 48-72 hours.  The sooner you bring you cat in to the veterinarian, the more likely they will be able to survive.  Once the blockage is removed, kidney function will usually return to normal with a few days of supportive fluid treatment.

When a blocked cat comes into the hospital, several methods may be attempted to relieve the blockage.  The veterinarian may try to flush out the stone and insert a urinary catheter which will be left in place for 12 hours to 3 days, depending on the blockage.  If flushing and catheterization are not successful the stone(s) will need to be removed surgically through the bladder.  Also, if a cat becomes blocked frequently, surgery is required to remove portions of the urethra and widen it so stones may be able to pass.

If a cat is brought to the hospital in the early stages of a blockage, several tests may be performed to determine the extent of the problem.  A urine test may be done to look for any crystals and/or infection and inflammation.  X-rays may also be performed to look for stones in the bladder and urethra.  The stones appear white on the x-ray and the veterinarian can see the size and number of stones present.  This will help the doctor determine if surgery is necessary.

Often after a cat has a blockage the veterinarian will change the cat's diet to a special prescription. Depending on the type of crystal seen, a change in food will help make the cats urine more acidic or alkaline to help prevent the formation of more crystals.  Along with diet therapy, frequent urinalysis should be performed in order to monitor the urine for pH and crystals.  This is critical in order to prevent future blockages.

Cats with urinary blockages usually live long and healthy lives if kept under veterinary supervision.  In most cases, all it takes is a simple change in diet to keep these cats thriving.  It is a problem to be constantly aware of in order to protect our pets, but it does not have to be deadly.  Please check daily to make sure your cat is drinking and urinating and at the first sign of a problem, call your vet.  It is always better to be safe than sorry.

This veterinary topic is dedicated to Keoki, who passed away recently due to a urinary blockage.  Our thoughts and prayers go out to the family, we are truly sorry for your loss.