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Common Feline Health Concerns


Urinating Outside of the Litter Box By Kristel Weaver, DVM

We see a lot of cats that eliminate outside their box.  It's a very stinky, frustrating problem.  I'll walk you through the questions I consider in order to figure out why a cat urinates inappropriately and some of the steps we take to correct it.

First question: Is this a medical problem or a behavioral problem?

Medical problems like a urinary tract infection, bladder stones, an inflamed bladder or a bladder tumor can make a cat urinate outside his or her box.  A metabolic disease, such as diabetes or kidney failure, which can make a cat drink and urinate a lot, can also make a cat urinate outside the box.  Have your veterinarian examine your cat and perform the diagnostic tests deemed necessary.  This will usually involve doing urine tests and blood tests. It may also involve either taking an X-ray or performing an ultrasound examination to look at your cat's bladder. If your cat is free of any medical problems, then there is a behavioral issue causing him or her to eliminate outside the box.

Second question: If it's a behavioral problem, then is your cat marking his or her territory, or does he or she have a litter box aversion or an inappropriate site preference?

Urine Marking - Cats that are marking their territory often urinate on vertical surfaces, like walls or the back of a chair.  When a cat marks (sprays), he or she will stand and their tail quivers.  Even when spayed and neutered, cats can still mark their territory.  Cats may mark their territory when a stray cat is hanging around, when there is a new pet or family member, or if they are stressed about something like a diet change or not enough attention.

Suggested treatment - First spay or neuter you cat.  Second, try to identify why your cat is marking.  Is there a stray cat coming around your house?  Did you add another pet to the household?  Have you switched foods? Have you been too busy to interact with your cat?  If you can identify the cause, take steps to correct it.  For example, block your cat's view of the stray with frosted window covers or put in motion sensor sprinklers to scare the stray cat away.  Separate new pets and introduce them slowly.  Make diet changes gradually.  Try to spend more time interacting with your cat.  Provide multiple feeding, perching and sleeping sites.  Third, give your cat more appropriate ways to mark his territory: add scratching posts or use Feliway products, which encourage facial rubbing instead of spraying, as a cat's method of territorial marking.

Litter Box Aversion – Cats with a litter box aversion urinate on horizontal surfaces, often close to their box.  They may be upset about the actual box, its location, or the litter in it.  Some cats may have difficulty physically getting in the box or may feel threatened by another pet hanging out close to it.

Suggested Treatment – Determine what type of box your cat prefers by temporarily giving him several different litter box options and seeing which he chooses.  In general, cats prefer a clean, uncovered box with a fine textured, unscented, clumping litter.  Most cats do not like their box in a busy, noisy, dark or smelly area.  If you have multiple cats you should have a box for each cat plus one more, in different areas of the house. Try putting the box in the location where your cat is eliminating inappropriately and then when he or she begins using it, gradually move it to the area you want him to go.

Litter box hygiene is important for any elimination problem but is especially critical for cats with litter box aversion.  Clean up urine outside the box with an enzymatic cleaner such as Anti-Icky-Poo or Nature's Miracle.  Scoop the box twice a day, change litter weekly and wash the box monthly with mild dish soap.  Carefully rinse away all traces of the detergent as cats find the smell of cleaning products offensive.

Inappropriate Site Preference – Some cats would rather urinate or defecate in places other than their litter box.  The most popular sites for cats are soft fabric (bedding, laundry, couch) or a smooth cool surface such as a tile floor or a sink.

Suggested Treatment – For cats with an inappropriate site preference, the goal is to make that site less attractive and their litter box more attractive.  First, try changing the texture of the site. For example, you can place a vinyl carpet runner nub side up on your bed. Or put a sheet of foil, plastic, sandpaper or double sided tape on your couch.  Second, change the purpose of that site: place your cat's food or water where he is eliminating.  Third, block access to the elimination site by closing doors, keeping laundry off the floor or putting a potted plant in the selected area.  Fourth, put the box as close as possible to the inappropriate location your cat has chosen, then gradually move it to where you want to keep it.  You don't have to try these ideas in the above order -- use whichever order you think best for your cat.  Finally, do everything you can to make the litter box more appealing; see the solutions for litter box aversion above for options.

For some cats, these environmental strategies are not fully effective and we also treat them with Prozac or other behavior modifying medications.

These are just some of the common causes and solutions. For additional information, one excellent resource from the College of Veterinary Medicine at The Ohio State University is http://indoorpet.osu.edu/cats/.  In all cases, I recommend you discuss your cat's specific issues with your veterinarian to come up with a specific treatment to get your cat using his or her box consistently.


Hairballs

What are hairballs?

A hairball is a small collection of hair or fur that forms in the stomach of a cat. Cats ingest the hair while grooming themselves. Hairballs are expelled from the stomach by means of vomiting. They are often cylindrical in shape and can include bits of food and other debris along with the densely packed fur. 

Why does my cat get them?

Grooming is very important to cats – they spend a large portion of the day cleaning themselves.  There are a number of reasons for this including removing strange odors that could attract predators, helping them cool down on a warm day, fur maintenance, stimulating blood flow, and of course, it’s quite relaxing! In the process, the cat’s tongue (covered with backward facing barbs called papillae) collects dirt, debris, and loose hair from its coat.  While some hair passes through the digestive tract without incidence, some hair may stay and collect in the stomach or small intestine. As the hair collects it forms a hairball. Usually this is the point your cat will begin to gag and retch in order to expel the buildup.

What are the symptoms?

It is a common site and sound to most cat lovers – their cat hunched over, head down, while making an awful sounding hacking, gagging, retching sound. This usually precedes the vomiting up of a hairball. Cats can sometimes vomit food or bile before eventually vomiting up the hairball. Other symptoms that can sometimes accompany hairballs are a decreased appetite and constipation.

Are they harmful?

While it is rare, hairballs can sometimes cause life-threatening blockages or be indicators of an underlying illness such as inflammatory bowel disease or cancer. Signs and symptoms to watch for include:

  • If your cat is showing the classic hairball symptoms of hacking, gagging, and retching on an ongoing basis but is not producing a hairball
  • Frequent vomiting of hairballs
  • Vomiting of hairballs combined with any of the following:
  • Lack of appetite
  • Lethargy
  • Constipation or diarrhea 

If you notice any of these symptoms in your cat or you are concerned about the frequency of hairballs occurring schedule an appointment with your veterinarian as soon as possible.

How can I prevent them?

There are several ways to help reduce the formation and frequency of hairballs:

  • Daily brushing of your cat’s coat can help decrease the amount of stray hairs ingested by your cat. This is especially important for long haired breeds that are even more prone to hairballs. However short hair cats can form hairballs as well and should not be overlooked. Brushing has the added benefits of preventing matted fur as well as being a bonding experience between you and your cat.
  • There are over the counter oral lubricants that can assist the passage of accumulated hair through your cat’s digestive tract. Ask your veterinarian if one of these products is right for your cat.
  • If your cat has frequent hairballs and your veterinarian has ruled out other conditions they may recommend a special formulated diet that helps reduce hairballs. Always check with your veterinarian first before deciding on a specially formulated diet for your cat.


Destructive Scratching

Some cats use their claws destructively indoors by clawing the furniture or carpet. For those cats, there are solutions to help curtail this habit.


Scratching

Scratching is a completely natural and normal behavior for your cat. It helps sharpen their claws, acts as a scent and visual marker, and aids in stretching.  Scratching is important to cats and feels good, however it can be destructive to a household and hard to control. By providing your cat with alternatives to your furniture, you can help discourage destructive scratching.

The first step is to provide some acceptable scratching material for your cat. Cat trees are ideal because not only can your cat scratch it, but it also gives them something to climb and perch on. Cats love high places from which to view their surroundings.  Make sure the cat tree is stable enough for your cat to run, jump, and climb on and has suitable material for their claws to dig into.

There are also horizontal posts available that can be placed on the ground for scratching, as well as vertical posts that hang from the door. These come in many different materials such as carpet, sisal rope, and corrugated cardboard. You may need to experiment to see which kind your cat likes best but a variety of options is ideal to prevent boredom.

If your cat has already started scratching furniture and carpet in your house, you may want to choose a cat tree or scratching post that is covered in a different material to avoid confusion. Sisal rope is usually very popular with cats. You will want to have scratching options placed throughout your home and especially near or in front of spots your cat has already decided to claw at.  You can slowly move the tree or post a little bit each day to where you would eventually like it to be located.

To help entice your cat to use their new post, try rubbing some catnip on it. When you see them scratching a post or playing on their tree, make sure to reward the good behavior with treats. This will help encourage appropriate scratching. It is usually not helpful to force a cat's paws onto a tree or scratching post.

There are a variety of ways to help make areas you do not want your cat to scratch less appealing.  While you are training your cat to use their new scratching materials you can place foil, plastic sheeting, or double sided tape on or around furniture.  Cats dislike sticky surfaces so double sided tape is an excellent deterrent. If you do not want to place double sided tape directly on your furniture, you can place carpet runners with the pointy side facing up in front of anything you want to mark as off limits. Use a water bottle to squirt your cat if you catch them scratching somewhere off limits. While these measures do not look attractive, it is hopefully temporary as your cat establishes appropriate clawing behavior. Patience and persistence are required in order to train your cat to create new scratching patterns.

Soft Paws

There are other options besides scratching posts and cat trees. First, there is a non-surgical alternative using Soft Paws. These are hollow "false nails" that fit like a cup over the claw and are glued in place. They stay on the nail for 4 to 6 weeks, and fall off as the nail grows. Replacement for most cat owners is a simple procedure. You can purchase a set of Soft Paws over the counter. We can glue on the first set of Soft Paws while you watch so you can see how we do it. After that we can continue to apply future sets of Soft Paws, or you can do it yourself at home.

Declawing

Another option is a surgical procedure referred to simply as declawing. This is the traditional method that has been performed to prevent cats from using claws. Declawing is a drastic and permanent solution when all other options have been exhausted. During the procedure the surgeon amputates the claw and last bone in each toe, from which the nail actually grows. It is essential that this bone be removed with the claw. This ensures that all the nail-producing cells are removed, thereby preventing re-growth of the nail. Either a small dissolvable stitch or tissue adhesive is used to close the skin together at the end of each toe when the procedure is completed.

This procedure is performed under general anesthesia and multiple forms of pain medications (local, injectable, oral, and patches) are often used to reduce post operative pain. The apparent degree of pain experienced by a cat varies from case to case. Your cat will stay at the hospital 1 to 2 nights with its feet bandaged and pain level monitored.

Once your cat goes it home it will likely need to continue on some form of pain medication as it is not uncommon for there to be discomfort. Your cat may experience pain for several days or even a week or more post operatively. During this time they will need to be confined in order to prevent trauma to the feet.

Cats rely on their claws for defense and should remain indoors after the surgery. There are reports that some cats show an increase incidence of biting following the surgery (presumably due to lack of claws for defense) but this is not a consistent finding. Any of our veterinarians will be happy to answer questions you may have about this procedure.


Fleas

Where does my cat get fleas?

The most common flea found on cats and dogs is the cat flea (Ctenocephalides felis). Rarely rabbit fleas or hedgehog fleas are also found on cats.

The most important source of cat fleas is newly emerged adult fleas from pupae in your house or yard.  Adult fleas live and feed on our pets but the female flea lays eggs, which fall off into the environment. Under favorable conditions, these eggs develop first into larvae and then into pupae. The pupae contain adult fleas that lie in wait for a suitable animal host. Modern carpeted centrally-heated homes provide ideal conditions for the year-round development of fleas. The highest numbers of flea eggs, larvae and pupae will be found in areas of the house where pets spend the most time, such as their beds and furniture. Even though fleas may be in your house, you probably won't see them; the eggs are too small to see without magnification and the larvae, which are just visible, migrate deep down in carpets, furniture or cracks in floors away from the light.


What effect do fleas have on my cat?

Many cats live with fleas but show minimal signs. However, the following problems can occur:

  • Some cats develop an allergy to flea bites, especially if they are repeatedly bitten. If these cats are bitten by fleas they groom or scratch excessively and develop skin disease.
  • Adult fleas live on animals and feed on blood. In kittens and debilitated animals this may cause anemia.
  • The flea acts as the intermediate host for the tapeworm (Dipylidium caninum). Tapeworm eggs, which are shed within tapeworm segments in cat feces, are eaten by flea larvae that develop into infected fleas. Cats become infested by swallowing infected fleas during grooming. Any cat with fleas is likely also to have a tapeworm infestation.


How can I get rid of fleas on my cat?

This can be a demanding task and requires a three-pronged approach. Fleas need to be eliminated from your cat, from any other cats and dogs that you have, from your home and from your yard. Even this rigorous approach may not give 100% control as there are other sources of fleas that are beyond your control such as other people's pets, wild animals and infested environments which your cat may come into contact with outside your house.

When it comes to environmental control, we must first understand the flea life cycle.


There are four stages in the life cycle of the flea:

  • Flea eggs are whitish and about 0.5 millimeter (mm) (1/32") in length. They are unlikely to be seen without a magnifying glass. Eggs are laid by the adult flea after taking a blood meal. The eggs are initially laid on the dog's skin but fall off into the environment to continue their lifecycle. Flea eggs constitute approximately 50% of the total flea population. Eggs may hatch in as little as 14 to 28 days, depending on environmental conditions. High humidity and temperature favor rapid hatching
  • Flea larvae are about 2-5 mm (1/8" to 1/4") in length. They feed on organic debris found in their environment and on adult flea feces. They dislike bright light and move deep into carpet fibers or under furniture, organic debris, grass, branches, leaves and soil. Flea larvae prefer warm, dark and moist areas. Outdoor larval development occurs only in shaded; moist areas where flea infested pets spend a significant amount of time. Our climate-controlled homes offer an ideal environment for the flea larvae to thrive.
  • The flea pupae produce a protective silk-like cocoon which is sticky. It quickly becomes coated with grime and debris, which acts as a useful camouflage. With warmth and humidity, pupae become adult fleas in 5-10 days. The adults do not emerge from the cocoon unless stimulated by physical pressure, carbon dioxide or heat. This is important since once fleas emerge from the cocoon they can only exist for a few days unless they are able to feed. Pre-emergent adult fleas can survive within the cocoon for up to 9 months. During this time they are resistant to insecticides applied to the environment. This is important to remember because adult fleas may emerge into the environment a considerable time after you apply insecticides in your home.
  • Once it emerges, the flea adult, unlike the larvae, is attracted to light and heads to the surface in order to encounter a passing host to feed upon. Two days after the first blood meal, female fleas begin egg production. In normal circumstances the adult female will live up to three weeks, laying approximately 40 eggs per day. The entire life cycle, from egg to adult flea can be completed in 14-28 days depending on environmental conditions.


What products are available to treat my cat?

Insecticides applied to cats are designed to kill adult fleas. Many products have limited effectiveness because they only work for a few hours after application. This is particularly true of flea shampoos and powders; they kill fleas present on your cat at the time of application but have little residual effect so the day after use the cat may again have fleas. There are new products with excellent residual activity that are available from your veterinarian. In addition to adulticides, there are several products on the market that contain insect growth regulators, which effectively sterilize the fleas and prevent flea infestations.

ALWAYS READ THE LABEL CAREFULLY - apply the product as instructed and repeat at the intervals stated.

Consult your veterinarian, as there are several alternatives available. Flea collars are very convenient but they don't work well or provide sufficient control for a flea allergic cat and are not generally recommended. Additionally, some flea collars, especially ones with a strong pesticide smell, may be harmful to some cats. Some cats will develop a skin reaction to collars. There are flea foams available that you brush into your cat's coat. Topical flea preventives are highly recommended because of their efficacy and ease of application.


How can I treat my home environment?

A number of different products are available which will kill the stages of the flea life cycle present in your home such as:

  • Insecticide sprays for use in the house
  • Sprays containing insect growth regulators (IGRs) for use in the house
  • Insecticides applied by professional pest control operatives in your house

Sprays for use in the house should be used in places where the flea eggs, larvae and pupae are likely to be. It is recommended that you treat the entire household first and then concentrate on the hot spots - your cat's favorite dozing spots - such as soft furniture, beds and carpets. Once they hatch from the egg, flea larvae move away from the light and burrow deep into carpets and into other nooks and crannies where it is difficult to treat. Be sure to move cushions, furniture and beds to spray underneath. Other places larvae are likely to live include baseboards and the cracks in wooden floors.


Your pet's bedding should be regularly washed in hot water or replaced. Regular and thorough vacuuming of your carpets, floors and soft furnishings can remove a large number of flea eggs, larvae and pupae that are present in your home. You will need to throw away the vacuum bag to prevent eggs and larvae from developing inside the vacuum cleaner. Vacuuming prior to the application of a spray to the house is recommended because the vibrations will encourage newly developed fleas to emerge from pupae, which will be killed by the insecticide.


How do I choose which products to use?

A flea control program needs to be individually tailored based on the lifestyle of your cat and other pets, and your family situation. Your veterinarian is the best person to advise you about safe and effective flea control products.


Are insecticides safe for my cat and my family?

Insecticides for flea control should be safe both for pets and humans provided the manufacturer's instructions are carefully followed. One should be particularly careful to avoid combining insecticides with similar modes of action. Always seek your veterinarian's advice if you are unsure about this and always tell your veterinarian about any flea control products you may be using other than those which he has prescribed.


Certain types of pets (e.g. fish, amphibians, reptiles and invertebrates) may be particularly susceptible to some products. Do not use any flea control products in the room in which these pets are kept without first consulting your veterinarian for advice.

I have not seen any fleas on my cat. Why has my veterinarian advised flea control?

Fleas are easy to find if a cat is heavily infested. If fleas are present in smaller numbers, it can be harder to see them and fleas move fast!  Try looking on the cat's stomach, around the tail base and around the neck. Sometimes adult fleas cannot be found but "flea dirt" can be seen. This is fecal matter from the flea that contains partially digested blood and is a good indicator of the presence of fleas. Flea dirt is seen as small black specks or coiled structures; when placed on damp white tissue, they dissolve, leaving a reddish brown stain. Flea dirt may be found in cat's bedding even when fleas cannot be found on the cat.

In cats that develop an allergy to fleas one of the symptoms is excessive grooming. Cats are very efficient at removing debris from their coat's using their tongues and may succeed in removing all evidence of flea infestation such as adult fleas and flea dirt. One of the most common causes of feline allergic skin disease is flea allergy dermatitis. To investigate this possibility your veterinarian may advise rigorous flea control even though no fleas can be found. If the cat's skin problem improves with flea control then it suggests that flea allergy is involved.

I noticed my cat had fleas after his return from boarding. Did he get fleas there?

Not necessarily. Newly hatched adult fleas can survive for up to 140 days within the pupa. When you and your pets are absent from home for extended periods of time these adult fleas remain in the pupae because no host is available. As soon as you or your pet returns home, these fleas will emerge in large numbers and jump onto cats, dogs and even people in the search for a blood meal.

Despite treating my cat for fleas he still has them. Is there a "super flea"?

There is no evidence of fleas developing resistant to insecticides, especially the newer once-a-month topical flea preventives. Apparent failure of treatment almost always results from improper application of the preventive, inadequate treatment of the home or exposure to other infested pets or environments. Consider treating sheds, cars and any outdoor sleeping spots. Bear in mind that your cat may be going into other people's houses. Most of these problems can be overcome by using an effective product on the cat to kill adult fleas in addition to treating your home.


Diabetes

What is diabetes mellitus?

Diabetes mellitus is a medical condition resulting in an excessive amount of glucose or sugar in the blood. This is caused by a deficiency of insulin, which is a hormone secreted by the pancreas.

The clinical signs seen in diabetes are largely related to the elevated concentrations of blood glucose and the inability of the body to use glucose as an energy source due to the deficiency of insulin.

Diabetes mellitus affects an estimated one in four hundred cats, and is seen more frequently in middle to old-age cats and is more common in males than females.

What are the clinical signs of diabetes mellitus?

The most common clinical signs seen in diabetic patients are an increase in water consumption and urination. Weight loss is also a common feature, and an increase in appetite may be noticed in some cats. Recognition of these signs is variable though, particularly because of the life-style of some cats. If a cat spends a lot of time outdoors, it may drink from ponds or pools of water outside rather than appearing to drink excessively from what is provided indoors. Cats that are fed canned or moist diets receive much of their water intake from their diet and increased water intake will be less easily recognized in these patients.

How is diabetes mellitus diagnosed?

The diagnosis of diabetes mellitus is made based on clinical signs, persistently elevated blood glucose concentration and the presence of glucose in the urine. However, a diagnosis of diabetes cannot be made on a single blood and urine sample as other conditions, in particular stress, may also cause a transient rise in glucose levels. Confirmation of diabetes may therefore require more than one blood sample collected over a period of one to five days.

How is diabetes mellitus treated?

Diabetes mellitus is a treatable condition. Although long-term treatment requires commitment and dedication, it can be rewarding to successfully manage this condition in a beloved pet.

Initial steps in treating a diabetic cat may involve removal of any predisposing causes for the diabetes. For example, the administration of some drugs predisposes cats to develop diabetes and withdrawal of these drugs may lead to resolution of the condition. Obese cats are more prone to develop diabetes and weight reduction can lead to resolution of the signs in some cats.

If there are no predisposing causes, or if correction of the predisposing causes does not lead to resolution of the diabetes, specific treatment is required. Although a small proportion of cats will respond to oral hypoglycemic medication, most cats will require insulin injections to control the diabetes.

During the initial stages of treatment, your cat will require several hospital visits until an appropriate insulin dosage is determined. Most cats will achieve initial stabilization within a few days to a few weeks. Most cats will require once or twice daily injection of a small dose of insulin. Very small needles are available which cause no pain to the cat, and within a short period of time the procedure becomes routine. Administration times, dosages and type of insulin will be determined by your veterinarian.

Do treated cats need to be monitored?

Yes, it is important to monitor treatment to make sure it is working properly, and to determine if any insulin dosage adjustments are necessary.

Monitoring can be done in part through the collection of occasional blood samples by your veterinarian, but it is particularly valuable to keep accurate records of the following information:

Daily records:

  • Time of insulin injection
  • Amount of insulin injected
  • Amount and time of food fed and eaten
  • Amount of water drunk

Weekly record:

  • Weight of the cat


In addition to these records, it can be valuable to monitor the quantity of glucose passed in the urine as a guide to the effectiveness of the treatment. This is best done on urine that is passed during the night or first thing in the morning. To collect urine, it is usually easiest to replace the normal cat litter with clean and washed aquarium gravel at night, which will not soak up any urine passed. The urine collected can either be tested by your veterinarian or they may supply you with a kit to test it yourself. If there is any marked change in the amount of glucose in the urine, this may indicate the need to alter the insulin dose, but you should never change the dose of insulin without first discussing it with your veterinarian. Changes in the insulin dose are usually based on trends in urine glucose concentrations, as there is normally some day-to-day variation.


What happens if my cat receives too much insulin?

If a cat receives too much insulin, it is possible for the blood sugar level to drop dangerously low. For this reason it is important to be very careful in ensuring the cat receives the correct dose of insulin.

The typical signs displayed by a cat with a very low blood sugar level are weakness and lethargy, shaking, unsteadiness and even convulsions. If a diabetic cat shows any of these signs it is important to seek immediate veterinary advice or attention. In mild cases of hypoglycemia, you may observe “wobbling” or “drunken” walk or appearance and the cat may not arouse when you call or pet them. In cases of mild or early hypoglycemia, you should administer approximately a tablespoon of corn syrup, honey or sugar solution by mouth. If more severe signs are displayed such as ataxia or severe incoordination and unsteadiness during walking, or convulsions, you should seek immediate veterinary care. Your veterinarian can advise you on specific emergency treatment of low blood sugar in your cat.


Kidney Disease

What do my cat's kidneys do?

The kidneys have many functions. They principally act to remove waste products from the blood stream, retain essential nutrients such potassium at the correct level, maintain hydration and produce urine.

What is chronic renal failure?

The kidneys have a large amount of spare capacity to perform their various functions so at least 70% of the kidneys need to be dysfunctional before any clinical signs are seen. In many cases this means that the damage to the kidneys has been occurring over a number of months or years (chronic) before failure is evident. Chronic renal failure (CRF) is most commonly seen in older cats. Only about 10% of the cases occur in cats less than three years old. Early signs of disease such as weight loss and poor coat quality are often dismissed as normal aging changes. In the initial stages of kidney disease, the kidneys cope with their inability to concentrate waste products by excreting them at a lower concentration over a larger volume. This is known as compensated renal failure. After approximately 70% of the kidney tissues are destroyed, there is a rapid rise in waste products in the bloodstream and an apparent sudden onset of severe disease.

What are the causes of CRF?

A large number of different disease processes can eventually lead to CRF including:

  • Congenital malformations of the kidneys - such as polycystic kidneys in long haired cats

  • Bacterial kidney infections called pyelonephritis 

  • Glomerulonephritis - damage to the kidney’s filtration membrane

  • Neoplasia - various tumors of the kidney, most commonly lymphosarcoma

  • Amyloidosis - this is the build-up of an unusual protein in the kidney that prevents the kidney from functioning normally

  • Viral infections such as feline leukemia virus (FeLV) or feline infectious peritonitis virus (FIP)

CRF is the end stage of a number of different disease processes rather than a specific condition in its own right.

How is the disease diagnosed?

Renal failure is usually diagnosed by looking at the level of two waste products in the bloodstream, blood urea nitrogen (BUN) and creatinine, in conjunction with  the urine specific gravity (USpG). Tests to measure the blood levels of other substances such as potassium, phosphorus and calcium as well as the red and white blood cell counts are important in order to determine the extent of failure and the best course of treatment.

Could the renal failure have been diagnosed earlier?

Unfortunately, this is very difficult as neither clinical signs of renal failure nor rises in BUN and creatinine are evident until significant loss of kidney function has occurred.


In earlier stages of disease there are no clinical signs to indicate that sophisticated renal function tests, which can pick up early renal damage, are required. We recommend that all senior pets have at least a urinalysis performed every six to twelve months to diagnose kidney disease at it earliest detectable level. A low urine specific gravity may indicate that at least two-thirds of the kidney tissues are damaged.

How does CRF affect my cat?

Because the kidneys perform a variety of different functions, the clinical signs of renal failure can be somewhat variable. The most common changes seen are weight loss, poor hair quality, halitosis (bad breath), variable appetite which may be associated with mouth ulcers, lethargy and depression. Less commonly, cats are seen to drink and urinate more and some will have vomiting and diarrhea. Rarely, renal failure is seen as sudden onset blindness.

What treatments are available?

Depending on the results of blood tests your veterinarian may be faced with several problems that require different treatments. Don't worry if the list below seems so long that you will never be able to administer all of the medications. The majority of cats can be effectively managed with diet change including supplementation and one or two other treatments.

  • Lowering the level of waste products in the bloodstream by feeding low protein and low phosphorus diets. These can be prepared at home or are available ready prepared from your veterinary practice. 
  • Phosphate binders - despite low phosphate in the diet, blood phosphorus levels remain above normal in some cats. Reducing blood phosphorus can have a major effect on improving your cat's well being and slowing disease progression. Phosphate binders such as aluminum hydroxide are given by mouth to further lower the amount of phosphorus absorbed through the gut wall. 
  • Antibiotics - many cats seem to respond well to antibiotics though the reason for this is not always clear. 
  • Potassium supplementation - cats in renal failure tend to lose too much potassium in the urine. This leads to muscle weakness, stiffness and poor hair quality. Low potassium levels may also contribute to the worsening of the kidney failure. 
  • Vitamins B and C - these vitamins are lost by the failing kidneys and need daily supplementation. 
  • Anti-emetics - for those cats that are experiencing vomiting, the use of anti-emetics reduces nausea, thereby improving appetite.
  • Blood-pressure lowering drugs - significant numbers of cats with kidney failure have high blood pressure. In some cases lowering their blood pressure may be necessary. 
  • Treatment of anemia - the kidneys also initiate the production of red blood cell in the bone marrow. Many cats with CRF are anemic due to a lack of stimulation of the bone marrow. Newer drugs have been developed to help stimulate bone marrow production and may be prescribed for your cat.

IT IS IMPORTANT THAT FRESH WATER IS AVAILABLE AT ALL TIMES BECAUSE CATS WITH RENAL FAILURE CAN DEHYDRATE RAPIDLY.

What is the cost of treatment?

Treatment costs will vary with each individual case. In the majority of cases, long term management is generally inexpensive.

How long can I expect my cat to live?

Unfortunately, once the kidneys are damaged, they have very limited ability to recover. Most CRF cases progress very slowly. With treatment, your cat may have several years of good quality, active life ahead.

This client information sheet is based on material written by Ernest Ward, DVM © Copyright 2005 Lifelearn Inc. Used with permission under license. June 23, 2014


Hyperthyroidism

The thyroid glands are located in the neck and play a vital role in regulating the body's metabolic rate. Hyperthyroidism is a disorder characterized by the overproduction of thyroid hormone and a subsequent increase in the metabolic rate. This is a fairly common disease of older cats. Although the thyroid gland enlarges, it is usually a benign or non-malignant change. Less than 2% of hyperthyroid cases involve malignant thyroid gland tumors.

Many organs are affected by hyperthyroidism, including the heart. The heart is stimulated to pump faster and more forcefully; eventually, the heart enlarges to meet these increased demands for blood flow. The increased pumping pressure leads to a greater output of blood and high blood pressure. About 25% of cats with hyperthyroidism have high blood pressure.

Are certain cats more likely to develop hyperthyroidism?

Older cats are at increased risk for developing hyperthyroidism. Environmental and dietary risk factors have been investigated and may play a role in predisposing some cats to hyperthyroidism, although the specific mechanisms are not known. No individual breed is known to be at increased risk, although the Siamese appears to have a somewhat increased incidence of hyperthyroidism compared to other breeds.

What are the clinical signs of hyperthyroidism?

The typical cat with hyperthyroidism is middle aged or older. The average age of affected cats is approximately twelve years. The most common clinical sign of hyperthyroidism is weight loss secondary to the increased rate of metabolism. The cat tries to compensate for this with an increased appetite. In fact, some of these cats have a ravenous appetite and will literally eat anything in sight!  Despite the increased intake of food, most cats continue to lose weight. The weight loss may be so gradual that some owners will not realize it has occurred, or the weight loss may be quite rapid. Affected cats often drink a lot of water and urinate more frequently. There may be periodic vomiting or diarrhea, and the fur may appear unkempt. In some cats, anorexia develops as the disease progresses.

Two secondary complications of this disease can be significant. These include hypertension (high blood pressure) and heart disease called thyrotoxic cardiomyopathy. Hypertension develops as a consequence of the increased pumping pressure of the heart. In some cats, blood pressure can become so high that retinal hemorrhage or detachment will occur and result in blindness. Heart problems develop because the heart must enlarge and thicken to meet the increased metabolic demands. Both of these problems are potentially reversible with appropriate treatment of the disease.

What causes hyperthyroidism?

Some of the risk factors for hyperthyroidism have been defined above. A specific cause for hyperthyroidism has not been identified. The possible role of dietary iodine continues to be investigated as a dietary influence on development of hyperthyroidism.

How is hyperthyroidism diagnosed?

In most instances, diagnosis of this disease is relatively straightforward. The first step is to determine the blood level of one of the thyroid hormones, called total thyroxine (or TT4). Usually, the TT4 level is so high that there is no question as to the diagnosis. Occasionally, a cat suspected of having hyperthyroidism will have T4 levels within the upper range of normal. When this occurs, a second test, usually either a Free T4 by Equilibrium Dialysis (FT4 by ED) or a T3 Suppression Test, is performed. If these tests are not diagnostic, a thyroid scan can be performed at a veterinary referral center or the TT4 can be measured again in a few weeks. 

How is hyperthyroidism treated?

Because less than 2% of cats with hyperthyroidism have cancerous growths of the thyroid gland, treatment is usually very successful.

Several tests are performed before choosing any form of treatment. These tests are needed to evaluate the overall health of the cat and predict the chances for treatment complications. Such tests include blood tests, urinalysis, and x-rays, EKG, blood pressure determination. Cardiac ultrasound or echocardiography may be recommended based on your cat’s condition.

There are three choices for treatment; any one of them could be the best choice in certain situations. Many factors must come into consideration when choosing the best therapy for an individual cat. The three treatment options for hyperthyroidism are:

1. Radioactive iodine. A very effective way to hyperthyroidism is with radioactive iodine therapy (I131). It is given by injection and destroys all abnormal thyroid tissue without endangering other organs. Treatment requires one or two weeks of hospitalization at a veterinary hospital licensed to administer radiation therapy. 

2. Surgery. Surgical removal of the affected thyroid lobe(s) is also very effective. Because hyperthyroid cats are usually over eight years of age, there is a degree of risk involved. However, if the cat is otherwise healthy, the risk is minimal. If the disease involves both lobes of the thyroid gland, two surgeries may be required, depending on the surgeon’s choice of procedures. In many cats, only one thyroid lobe is abnormal, so only one surgery is needed. 

If surgery is the treatment method chosen, the cat is often treated with an anti-thyroid medication for several weeks prior to the operation. During that time, the ravenous appetite should subside and the cat will probably gain weight. Some cats also have a very fast heart rate and high blood pressure; these problems can be managed with medication before surgery. 

The cat is generally hospitalized for one night following surgery and returns home feeling quite well. It should eat normally after returning home. One to two weeks, after surgery, another TT4 level is measured. 

3. Oral medication. Administration of an oral drug, methimazole (Tapazole®), can control the effects of the overactive thyroid gland. Some cats have reactions to the drug, but that number is fairly small (less than 20%). However, the side-effects may begin as late as six months after the beginning of treatment and can include vomiting, lethargy, anorexia, fever, and anemia. Methimazole blocks the production of excess thyroid hormone rather than destroying the abnormal thyroid tissue. Therefore, the drug must be given for the remainder of the cat's life. Periodic blood tests must be done to keep the dosage regulated and to ensure that no adverse side-effects are developing. Blood tests are usually performed every three to six months for cats receiving methimazole. This type of treatment is appropriate for the cat that is a poor surgical risk due to other health problems or is exceptionally old. As stated above, it may also be used for a few weeks to stabilize the cat that is at increased surgical risk because of cardiac complications. 

Recurrence of the disease is a possibility in some cats. It is uncommon after radioactive iodine therapy. When surgery is done, recurrence is possible if abnormal thyroid cells are left in the cat. The remaining cells will likely grow causing the disease to recur. However, this occurs less than 5% of the time and usually two to four years after surgery. Another possibility for disease recurrence is that one lobe of the thyroid gland was normal at the time of surgery so it was not removed. Then, months or years later, it becomes abnormal.

What is the prognosis for hyperthyroidism?

Many owners of cats with hyperthyroidism are hesitant to have radiation therapy or surgery because of their cat's advanced age. But remember, age is not a disease. The outcomes following both surgery and radiation therapy are usually excellent, and most cats have a very good chance of returning to a normal state of health. Cats managed medically also often do very well as long as the medication is administered routinely and follow-up blood and diagnostic test schedules are performed.

Can hyperthyroidism be prevented?

There are no preventive measures for hyperthyroidism, but middle-aged and senior cats should receive a complete physical examination by a veterinarian every six to twelve months. Special attention should be given to thyroid enlargement and the typical clinical signs of hyperthyroidism. Annual blood and urine tests are important in all cats over age six to detect hyperthyroidism before potentially irreversible damage occurs.