Flooding the Litterbox: Chronic Kidney Disease and your cat

CHRONIC KIDNEY DISEASE: An Overview

Before we re-write the book on Chronic Kidney Disease, please note that there are two extremely thorough and excellent resources for people with cats that have Chronic Kidney Disease (CKD) that we would like to recognize: 

Feline CRF (Chronic Renal Failure) Information Center
Tanya's Comprehensive Guide to Feline Chronic Kidney Disease

What is meant by the terms “Chronic Kidney Disease” and "Chronic Kidney Failure"?

The term "chronic kidney failure" suggests that the kidneys have stopped working and are, therefore, not making urine.  However, by definition, kidney disease is the inability of the kidneys to remove waste products from the blood.  This definition can occasionally create confusion because some will equate "kidney failure" with "failure to make urine".  Kidney disease is NOT the inability to make urine.  Ironically, most cats in kidney failure are actually producing large quantities of urine, but the body’s wastes are not being effectively eliminated. This is why many people avoid the term "kidney failure" and prefer "kidney disease". Because the kidneys are so efficient at their job and because cats are so adept at hiding their illnesses, it has been determined that a cat can lose up to 75% of normal kidney function before they begin to act sick. This is one reason that annual checkups with your veterinarian are so important!

There does come a point in CKD at which a cat's kidneys have been destroyed to the point where urine is no longer produced (anuria), but hopefully, the problem is recognized, discussed and treated before this is the case.

When is this likely to happen in my cat?

Commonly, chronic kidney disease is considered to be the result of aging - a “wearing out” process.  Most of the time, when chronic kidney disease is diagnosed, the cause is unknown. Biopsy of the chronic kidney usually results in a non-specific assessment called "chronic interstitial nephritis" - a hardening and inflammation of the filtration structures in the kidney. 

There are some known contributing factors to kidney disease:

• Polycystic Kidney Disease:  an inherited disease seen in certain purebreds where one or more fluid-filled cysts start to gradually replace normal kidney tissue 
• Kidney tumors: lymphoma is a common type of cancer seen in cats, and it can affect many different organs, including the kidneys. White Blood Cells called lymphocytes become affected and interfere with normal kidney structure
• Infections: bacterial infection of the kidneys (known as 'pyelonephritis') may cause enough damage to the kidneys to cause CKD. Kidney infections are usually a complication of a long-standing, untreated urinary tract infection, but can occur more quickly in older cats with dilute urine, cats on immunosuppressive drugs, or cats with concurrent diseases such as diabetes or FIV.
• Toxins: certain toxins and drugs can damage the kidneys - for example, cats that eat plants from the lily family, drink antifreeze or ingest pills from the pain-reliever family like acetominophen or ibuprofen
• Glomerulonephritis: there are small filtration units in the kidneys called "glomeruli" that filter toxins from the bloodstream. These filters can become inflamed for a variety of reasons and if the inflammation is prolonged, this can lead to CKD

For most cats, the early signs occur at about 10-14 years of age. However, some cats may experience early onset kidney disease at 5-7 years or younger. About 20-50% of cats will be diagnosed with CKD at some time in their lives.

What changes are likely to occur in my cat?

The kidneys are the body's filters, removing toxins from the blood and excreting them in the urine. When aging causes the filtration process to become inefficient and ineffective, blood flow to the kidneys is increased in an attempt to increase filtration.  This results in the production of more urine.  To keep the cat from becoming dehydrated, due to increased fluid loss in the urine, thirst is increased so the cat drinks more water.  

Other job functions of the kidneys:

• Maintaining hydration - the body's water balance
• Maintaining balance of salts and electrolytes
• Maintaining the acid balance of the body
• Maintaining normal blood pressure
• Producing hormones involved in calcium processing, red blood cell production, blood clotting and immune system health

Early signs of CKD:

• increased water consumption (polydipsia)
• increased urine production (polyuria) with or without litterbox avoidance
• mild or gradual weight loss 

Signs of more advanced kidney disease include:

• loss of appetite/severe or rapid weight loss
• depression or lethargy
• vomiting
• diarrhea
• poor coat
• anemia
• very bad breath (uremia)
• occasionally, ulcers will be found in the mouth

Additionally, cats with kidney disease tend to have associated high blood pressure.

How is chronic kidney disease diagnosed?

The diagnosis of kidney disease is made by determining the level of two waste products in the blood:  blood urea nitrogen (BUN) and blood creatinine.  A urinalysis is also needed to complete the study of kidney function, with special attention paid to the "specific gravity" of the urine. Urine specific gravity is a measure of the "stuff" (such as proteins) in the urine that make it different than water. Since cats are descended from desert animals, they are very good at concentrating their urine - eliminating a lot of "stuff" and conserving a lot of water. Average specific gravity of cat urine is greater than 1.035, and may be as high as 1.060 if they eat a dry-food only diet. If the urine specific gravity drops below 1.035, it can be a red flag that indicates the cat is not concentrating urine well for some reason - for example: drinking more water than usual or losing kidney function. Comparing the BUN and creatinine levels in the blood to the urine specific gravity can be very informative to the veterinarian.

Although BUN and creatinine levels reflect kidney failure, they do not predict it.  A cat with marginal kidney function may have normal blood tests.  If that cat is stressed with major illness or surgery, the kidneys may fail, sending the blood test levels quickly into the abnormal range. Additionally, other factors can affect the body's BUN and creatinine levels, such as kidney infection, hyperthyroid disease, muscle loss, and anorexia (lack of food intake).

Since this is basically just a wearing out process, can it be treated with anything other than a kidney transplant?

Yes, it can. We must recognize that your cat’s kidneys have reached this point due to aging, so they will never be normal again, but many cats still have enough functional kidney tissue so treatment can be very rewarding.

Treatment generally has two phases.  If your cat has reach a crisis, the first phase is to “restart” the kidneys.  The cat is hospitalized and large quantities of intravenous fluids are given to “flush out” the kidneys.  This flushing process, called diuresis, helps to stimulate the kidney cells to function again.  If enough functional kidney cells remain, they may be able to adequately meet the body’s needs for waste removal.  Fluid therapy includes replacement of various electrolytes, especially potassium.  Other important aspects of initial treatment include proper nutrition and drugs to control vomiting and diarrhea.

There are some exciting new developments in diagnosis and treatment of feline chronic kidney disease that will hopefully be very beneficial when they become available outside of university research settings.

A newly discovered biomarker of kidney disease may provide earlier detection and allow for closer monitoring and better, earlier treatments.

Stem cell therapy has been showing some promise in treating feline kidney disease, too. The stem cells for this therapy are cultivated from the fat of young, healthy cats; donor animals are not harmed.

What can I expect from this phase of treatment?

There are three possible outcomes from the first phase of treatment:

1) The kidneys will resume functioning and continue to function for a few weeks to a few years. 
2) The kidneys will resume functioning during treatment but fail again as soon as treatment stops. 
3) Kidney function will not return. 

Unfortunately, there are no reliable tests that will predict the outcome. The best your veterinarian can
do is assess the response of the cat's blood values and attitude while hospitalized and draw on their experience as to whether they recommend continued treatment, and if so, how aggressive that treatment needs to be to keep your cat healthy. A close relationship with your veterinarian will help them design a continuing treatment plan to keep your cat feeling healthy for as long as possible. That plan will need to be continually adjusted based on your cat's progress.

 If the first phase of treatment is successful, what happens next?

The second phase of treatment is to keep the kidneys functioning as long as possible. This is accomplished with one or more of the following, depending on the situation:

1. A high quality diet.  This helps to keep the blood tests as close to normal as possible, which usually makes your cat feel better.  We can recommend a commercially prepared food that has the quantity and quality of protein needed by your cat.

2. Potassium supplementation.  Potassium is lost in the urine when urine production becomes excessive.  A potassium supplement will replace that loss.  Low potassium levels have been shown to further reduce kidney function.  This is the second reason that a potassium supplement is recommended.  Monitoring of your cat’s potassium will guide our decision to supplement.

3. A phosphate binder.  One of the secondary things that occurs in kidney failure is an elevation of the blood’s level of phosphorus.  This also contributes to lethargy and poor appetite.  Certain drugs will bind excess phosphates in the intestinal tract so they are not absorbed, resulting in lower blood levels of phosphorus.  Phosphate binders are helpful only when feeding a phosphate restricted diet, as there is far too much phosphate in a  “normal diet” for these binders to be of benefit.

4. Fluids given at home.  Once your cat is stabilized, fluids can be given under the skin (subcutaneously). This serves to continually “restart” the kidneys as their function begins to fail again.  This is done once daily to once weekly, depending on the degree of kidney disease.  Although this might not sound like something you can do, you will be surprised at how easily the technique can be learned and how well most cats will tolerate it.

5. A drug to regulate the parathyroid gland and calcium levels.  Calcium and phosphorus must remain at about a 2:1 ratio in the blood.  The increase in blood phosphorus level, as mentioned above, stimulates the parathyroid gland to increase the blood calcium level by removing it from bones.  This can be helpful for the sake of the normalizing calcium:phosphorus ratio, but it can make the bones brittle and easily broken.  Calcitriol  can be used to reduce the function of the parathyroid gland and to increase calcium absorption from the intestinal tract.

6. A drug to stimulate the bone marrow to produce new red blood cells.  The kidneys produce erythropoietin, a hormone that stimulates the bone marrow to make red blood cells.  Therefore, many cats in kidney failure have a low red blood cell count, anemia.  Epogen, a synthetic form of erythropoietin, will correct the anemia in most cats.  Unfortunately for some cats, the drug cannot be used long term because the immune system recognizes the drug as "foreign" and will make antibodies (immune proteins) against it.

How long can I expect my cat to live?

The prognosis is quite variable depending on response to the initial stage of treatment and your ability to perform the follow-up care.   However, we encourage treatment in most situations because many cats will respond and have good quality life for up to 4 years. 

How could my cat be sick? He acts like a kitten! - Hyperthyroid disease and your cat

THE MANY FELINE FACES OF HYPERTHYROIDISM 

What is hyperthyroidism?

The thyroid is a gland located in the neck. It plays a very important role in regulating the body's rate of metabolism. Hyperthyroidism is a disorder characterized by the overproduction of thyroid hormone (thyrotoxicosis). When excessive amounts of thyroid hormone are in the circulation, the body's metabolism speeds up greatly.

Location of the thyroid gland

 

1: Normal thyroid gland. 2, 3: parathyroid glands. 4: enlarged thyroid gland

Hyperthyroidism is a fairly common disease of older cats. It is estimated that about 5-10% of cats will develop hyperthyroidism in their lifetimes. Although the thyroid gland enlarges, it is usually a non-malignant (benign) change.  Less than 2% of hyperthyroid cases involve a malignant change in the gland.

What does this do to the cat?

The typical cat with hyperthyroidism is middle aged or older; on the average, affected cats are about 13 years of age. The rapid rate of metabolism causes 95-98% of cats with this disease to lose weight. The cat tries to compensate for this with an increased appetite. In fact, 67-81% of these cats have a ravenous appetite and will literally eat anything in sight! Despite the increased intake of food, most cats gradually lose weight. The weight loss may be so gradual that some owners will not even realize it has occurred.  Affected cats usually drink a lot of water and urinate frequently. There may be periodic diarrhea or vomiting, and the hair coat may be unkempt. As the disease progresses, the cat's appetite may decline to the point of anorexia.

In addition to:

• weight loss
• increased appetite
• vomiting
• diarrhea
• unkempt coat

other signs of hyperthyroidism that may be noticed include:

• increased thirst
• increased or more frequent urination, larger clumps in the litterbox, or inappropriate urination outside the litterbox
• increased activity
• increased vocalizations 
• pacing or restlessness
• anxiety
• panting or rapid breathing

How is hyperthyroidism diagnosed?

The disease is most commonly diagnosed by determining the blood level of one of the thyroid hormones; the hormone most frequently measured is T4. Usually, the T4 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 range of normal cats. In this case, a second test, called a T3 Suppression Test, is performed. If this is not diagnostic, a thyroid scan can be performed at a veterinary referral center.

Hyperthyroid cat before becoming hyperthyroid, and again at the time of I131 treatment

Is this disease treatable?

Because less than 2% of these cats have cancerous growths of the thyroid gland, treatment is usually very successful.  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 therapeutic option for a particular cat.

What would happen if I chose not to treat my cat's hyperthyroidism?

Hyperthyroid is a deadly disease if left untreated. The effects that hyperactive metabolism has on the body are progressive, and this is a disease that will not resolve on its own. Over time, a cat that is hyperthyroid will develop problems associated with malnutrition because the overactive metabolism is using up calories and nutrients more quickly than usual. Add to that the likely side effects of vomiting and diarrhea, and an untreated cat will also become severely dehydrated.

The increased heart rate of a hyperthyroid cat will cause the heart muscle to thicken, and many will develop cardiomyopathy (poor muscle contractions) and eventual congestive heart failure. The high blood pressure that often goes hand in hand with hyperthyroid disease can cause damage to many sensitive organs in the body, including the kidneys, the eyes and the brain - as these blood vessels rupture from constant high pressure, blood supply is lost and tissues become unhealthy. This can cause kidney disease, neurologic effects due to damaged brain tissue, and blindness if the eyes are affected.

1) Radioactive iodine.  Probably the safest, and definitely the most effective way to destroy the abnormal tissue is with radioactive iodine (I131) therapy. In 95% of cats treated with I131, the cure is complete and permanent. Radioactive iodine treatment for cats requires one to three weeks of hospitalization at a veterinary clinic licensed to administer radiation therapy, and involves administration of the iodine via injection or oral capsule. The iodine is concentrated in the thyroid gland and destroys the overactive cells. At Exclusively Cats Veterinary Hospital Cats RadioIodine Treatment Center, the cats are treated with an oral dose and isolated for one week at the hospital followed by one to two weeks of isolation within the home.

Here is a vivid demonstration of a cat before and 3 months after treatment.

2) Surgery.  Surgical removal of the affected thyroid lobe(s) (thyroidectomy) is also very effective.  Because hyperthyroid cats are usually over 10 years of age, there is a degree of anesthetic risk involved, but not necessarily any more risk than for other cats of similar age.  However, the risk is much less than most people think, as long as the cat is otherwise healthy.  Tests are done before surgery to evaluate the cat and predict the chances for complications. 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. Possible side effects include possible damage to the parathyroid gland, which is intimately associated with the thyroid gland, possible post-surgical hypothyroidism (under-functioning of the remaining thyroid gland, or as a result of bilateral thyroid removal).

3) Oral medication.  Administration of an oral drug, methimazole, can control the effects of the overactive thyroid gland.  After starting the medication, results can be seen in just 2-3 weeks. Some cats have reactions to the drug, but that number is fairly small (less than 20%). However, the side effects may begin as many as six months after the beginning of treatment and can include vomiting, lethargy, anorexia, fever, and anemia. Less frequently, cats may develop facial itching, clotting disorders and liver malfunctions. Methimazole does not destroy the abnormal thyroid tissue, but rather prevents the production of excess thyroid hormone.  Therefore, the drug must be given for the remainder of the cat's life. If the medication is stopped, hormone production will return to high levels again and the cat's symptoms will return.

Some cats can be particularly difficult to regulate, or may be poorly sensitive to this medication, which can be a downside to choosing this method of treatment. Other cats are difficult to medicate and would be better served by I131 treatment. Methimazole is a medication that some cats metabolize well in a transdermal form, but this option is not tolerated by all cat, and there is some risk to the owner in applying a thyroid-inhibiting medication that is absorbed through the skin, so appropriate handling of the medication is important, and transdermal medication may not be an appropriate choice for cats living in a home with small children. Periodic blood tests must be done to keep the dosage regulated. This type of treatment is appropriate for the cat that is a poor surgical risk due to other health problems.

4) Hill's Y/D diet.  Because the thyroid gland needs iodine to make thyroid hormone, feeding a diet with minimal iodine content should decrease the thyroid hormone levels of the cat. Feeding trials have indicated that after 3 weeks of feeding ONLY this diet - no treats, no human foods - thyroid levels are significantly reduced in most cats. Cats will not become hypothyroid while eating this diet, and a two year study suggests that cats that are NOT hyperthyroid that eat this diet will not suffer adverse effects. However, in practice, we have had a very difficult time getting cats to eat this diet, so while it is an option, it is a pricy (4 pounds of food is about $25 dollars and lasts about 3 weeks for a 7 pound cat) experiment that may not always pan out. There are many people who have had excellent results with this diet change, however, so it is definitely a viable treatment option. This treatment is not curative and the cat will need to remain on this diet for the rest of its life.

How Y/D diet works

If I elect to have surgery for my cat, what is the procedure?

If surgery is the treatment method chosen, the cat is put on methimazole for one to four weeks before surgery. This treatment should cause the ravenous appetite to subside, and your cat will probably gain weight. Some cats also have a very fast heart rate and may be medicated before surgery with another drug, such as Atenolol. After one to two weeks, another T4 level in the blood is measured.

The operation is performed in a sterile operating room and your cat is under general anesthesia. An incision is made along the neck just below the throat and the enlarged thyroid gland is removed. The skin is sutured together.

Your cat is generally hospitalized for one night following surgery and returns home feeling quite well. He or she should eat normally after returning home. 

Can hyperthyroidism occur again?

Recurrence is a possibility in some cats. Recurrence is uncommon after radioactive iodine therapy.  When surgery is performed, the chance of recurrence is slightly greater. It is usually not possible to surgically remove all of the cells from the abnormal thyroid gland. If those remaining cells grow, the disease may recur. However, this occurs less than 10% of the time and usually after 2-4 years.  Another possibility is that one side of the thyroid gland appeared normal at the time of surgery so it was not removed. Then, months or years later, it may become abnormal.

I think my cat is too old for anything but treatment with the oral medication or diet change.  Do you agree?

Many owners of cats with hyperthyroidism are hesitant to have radiation therapy or surgery because of their cat's advanced age. But remember, old age is not a disease. The outcomes following both surgery and radiation therapy are usually very positive, and most cats have a very good chance of returning to an excellent state of health. Some of the cats referred to our hospital in Waterford, Michigan, for radioactive iodine treatment have been as old as 20 years of age, and have done very well!

Diabetes and your cat

DIABETES MELLITUS IN CATS

November is National Pet Diabetes Month!

Somewhere between 1 in 100 and 1 in 500 cats will develop diabetes during their lifetime. As pet obesity becomes more of a problem, these numbers are expected to increase.

What is diabetes mellitus?

There are two forms of diabetes in cats: diabetes insipidus and diabetes mellitus.  Diabetes insipidus is a very rare disorder that results in failure to regulate body water content.  The more common type of diabetes seen in cats is called diabetes mellitus.  This treatable disease is seen on a fairly regular basis, usually in cats 5 years of age or older. The highest risk categories are older cats, obese cats, and male cats. Other contributing factors can include hyperthyroid disease (elevated thyroid function), chronic pancreatitis (long term inflammation of the pancreas), Cushing's Disease (also known as hyperadrenocorticism, or excessive production of cortisol by the adrenal glands), acromegaly (excessive growth hormone production by the pituitary gland), and the use of steroid medications. In some countries, the Birman breed appears to be at higher risk for diabetes, but this is not the case in the United States.

Simply put, diabetes mellitus is a failure of the pancreas to regulate blood sugar.  The pancreas is a small but vital organ that is located near the liver and stomach.  It is shaped like an "L" and is made up of two different groups of cells.  One type of cells produces the enzymes necessary for proper digestion. These enzymes help break down or "metabolize" fats, proteins and carbohydrates. The other group, called beta cells, produces the hormone called insulin. Insulin is in charge of instructing the cells of the body to use the glucose that enters the blood stream after sugars are broken down.

Some people with diabetes take insulin shots and others take oral medication.  Is this true for cats?

In cats, two types of diabetes mellitus have been discovered.  Both types are similar in that there is a failure to regulate blood sugar, but the basic mechanisms of disease differ somewhat between the two groups. 

1.         Type I, or Insulin Dependent Diabetes Mellitus, results from total or near-complete destruction of the beta cells. This is the most common type of feline diabetes.  As the name implies, cats with this type of diabetes require insulin injections to stabilize blood sugar. 

2.         Type II, or Non-Insulin Dependent Diabetes Mellitus, is different because some insulin-producing cells remain.  However, the amount produced is insufficient, there is a delayed response in secreting it, and the tissues of the cats body are relatively resistant to it.  These cats may be treated with an oral drug that stimulates the remaining functional cells to produce or release insulin in an adequate amount to normalize blood sugar.  Alternatively, they may be treated with insulin.  Cats with NIDDM may ultimately progress to total beta-cell destruction and then require insulin injections.

Why is insulin so important?

The role of insulin is much like that of a gatekeeper: it stands at the surface of body cells and opens the door, allowing glucose to leave the blood stream and pass into the cells.  Glucose is a vital substance that provides much of the energy needed for life, and it must work inside the cells.  Without an adequate amount of insulin, glucose in unable to enter the cells.  It builds up in the blood, setting in motion a series of events, which can ultimately prove fatal.  When cells are not able to use the glucose in the blood because insulin is deficient, the cells become starved for energy.  Because cells need energy to function, and a cat's body needs functional cells to remain alive, the body starts breaking down stores of fat and protein to use as alternative energy sources.

Because the cat's cells are starving, the cat eats more, but because the diabetic cat can only get energy from stored fat and protein, and not the food that he is eating, he loses weight. Thus, we have weight loss in a cat with a ravenous appetite.  The body tries to get rid of the excess glucose by eliminating it in the urine.  However, along with the glucose, a large amount of body fluid is eliminated, too, because glucose (blood sugar) attracts water.  This results in the production of a large amount of urine.  To avoid dehydration, the cat becomes thirsty and drinks more and more water.  Thus, we have the four classical signs of diabetes:  

• Weight loss
• Ravenous appetite
• Increased water consumption
• Increased urination

How is diabetes mellitus diagnosed?

The diagnosis of diabetes mellitus is based on three criteria: the four classical clinical signs, the presence of a persistently high level of glucose in the blood stream, and the presence of glucose in the urine. 

The normal level of glucose in the blood is 80-120 mg/dl (3.9-6.1 mmol/L).  It may rise to 250-300 mg/dl 13.8-16.5 mmol/L) following a meal or when the cat is very excited.  However, diabetes is the only common disease that will cause the blood glucose level to rise above 400 mg/dl (22 mmol/L).  Some diabetic cats will have a glucose level as high as 800 mg/dl (44 mmol/L), although most will be in the range of 400-600 mg/dl (22-33 mmol/L).

To keep the body from losing its needed glucose, the kidneys do not allow glucose to be filtered out of the blood stream until an excessive level is reached.  This means that cats with a normal blood glucose level will not have glucose in the urine.  Diabetic cats, however, have excessive amounts of glucose in the blood, so it will be present in the urine.

What are the implications for my cat and me?

For the diabetic cat, one reality exists: blood glucose cannot be regulated normally without treatment. Short term, the cat can compensate by digesting body stores of fat and protein, but over time, a condition called "ketoacidosis" can occur. This is due to the body's inability to handle excessive breakdown of fat and protein for energy - the waste products, called "ketones" build up in the blood and lower the blood pH, making it more acidic. Because the diabetic cat is already dehydrated, the situation becomes more severe. The signs of diabetic ketoacidosis (DKA) are:

• a ravenous cat that now has no appetite
• vomiting
• diarrhea
• lethargy
• weakness
• dehydration
• respiratory abnormalities

 If a diabetic cat is having symptoms such as these, he should see a veterinarian immediately, as DKA can often require intensive care and IV fluid therapy.

Diabetic cats may develop unhealthy skin and flaky coat, liver disease, and secondary bacterial infections. Because diabetics have very dilute and sugar-filled urine, they are at higher risk than the average cat for urinary tract infections. Untreated diabetics may become weak, developing a condition called "diabetic neuropathy". Cats with this disorder often walk with their hocks touching the ground and have trouble jumping.

Although the cat can go a day or so without treatment and not get into a crisis, treatment should be looked upon as part of the cat's daily routine.  Treatment almost always requires some dietary changes.  Whether an individual cat will require oral therapy or insulin injections will vary. 

As for the owner, there are two implications: financial commitment and personal commitment. 

When your cat is well regulated, the maintenance costs are minimal.  The oral medication, insulin, and syringes are not extremely expensive.  However, the financial commitment is significant during the initial regulation process and if complications arise. 

If applicable,  your cat will be hospitalized for a few days to deal with the immediate crisis and to begin the regulation process.  The "immediate crisis" is only great if your cat is so sick that it has quit eating and drinking for several days. Ketoacidotic cats may require a week or more of hospitalization with quite a bit of laboratory testing. 

The financial commitment may again be significant if complications arise.  We will work with you to try and achieve consistent regulation, but some cats are difficult to keep regulated.  It is important that you pay close attention to instructions related to administration of medication, to diet, and to home monitoring.  Another complication that can arise is hypoglycemia or low blood sugar. Severe hypoglycemia can be fatal.  Hypoglycemia or low blood sugar is most commonly due to inconsistencies in treatment or because some cats can have a spontaneous remission of their disease.  

Your personal commitment to treating your cat is very important in maintaining regulation and preventing crises.  Most diabetic cats require insulin injections twice daily, at about 12 hour intervals.  They must be fed the same food in the same amount on the same schedule every day.  If you are out of town, your cat must receive proper treatment while you are gone.  These factors should be considered carefully before deciding to treat a diabetic cat.

What is involved in treatment?

The best one word answer to that question is "consistency".  Your cat needs consistent administration of medication, consistent feeding, and a stable, stress-free lifestyle.  To best achieve this, it is preferred that your cat lives indoors.  Although that is not essential, indoor living removes many uncontrollable variables that can disrupt regulation.

Drawing a dose of Lantus insulin from an insulin pen

Your cat's feeding routine is also important.  The average cat prefers to eat about 10-15 times per day, one mouthful at a time.  This means that food is left in the bowl at all times for free choice feeding.  However, this is not the best way to feed a diabetic cat.  The preferred way is to feed twice daily, just before each insulin injection.  If your cat is currently eating on a free choice basis, please try to make the change.  However, if your cat will not change or if you have several cats that eat in a free choice fashion, you may find that this change is not practical.  If a two-meals-per-day feeding routine will not work for you, it is still very important that you find some way to accurately measure the amount of food that is consumed.

Fortunately, there are more and more advanced feeding options available to help monitor your cat's food intake. Some new products on the market that may be helpful are the MeowSpace Feeding and Litterbox Solution, or the soon-to-be-available Sure Feed microchip or collar tag activated pet feeder. An exciting prospect that is on the horizon is the Bistro Facial Recognition Smart Feeder. All these feeding options help multi-cat households control food access among their multiple cats to ensure that they have a better idea how well their diabetic is eating.

Since obesity is one of the predisposing factors for diabetes, making sure that your cat maintains a healthy, active lifestyle is important. Encouraging diabetic cats to eat a healthy, low carbohydrate, high protein diet, including 3-6oz canned food daily, may help encourage healthy weight loss.

                About Insulin

Insulin comes in an airtight bottle that is labeled with the insulin type and the concentration.  Before using, mix the contents.  It says on the label to roll it gently, not shake it.  The reason for this is to prevent foam formation, which will make accurate measuring difficult.  If it is not shaken properly, it will not mix well, and dosing will not be accurate.  Therefore, the trick is to shake it vigorously enough to mix it without creating foam.  Since bubbles can be removed (as described later), it is more important to mix it well than to worry about foam formation. 

Insulin is a hormone that will lose its effectiveness if exposed to direct sunlight or high temperatures.  It should be kept in the refrigerator, but it should not be frozen.  It is not ruined if left out of the refrigerator for a day or two, although this is not advisable.  Insulin is safe as long as it is used as directed, but it should be kept out of reach of children.

** You should replace your bottle of insulin every 6 months, regardless if the entire content has been used.  Studies have found that insulin loses its effectiveness over a long period of time. **

                Drawing up the Insulin

Have the syringe and needle, insulin bottle, and cat ready.  Then, follow these steps:

1)        Remove the guard from the needle, and draw back the plunger to the appropriate dose level.

2)        Carefully insert the needle into the insulin bottle. 

3)        Inject air into the bottle; this prevents a vacuum from forming within the bottle. 

4)        Withdraw the correct amount of insulin into the syringe.

Various brands of U-100 insulin syringes

Before injecting your cat with the insulin, check that there are no air bubbles in the syringe.  If you get an air bubble, draw twice as much insulin into the syringe as you need.  Then withdraw the needle from the insulin bottle and tap the barrel of the syringe with your finger to make the air bubble rise to the nozzle of the syringe.  Gently and slowly expel the air bubble by moving the plunger upward.

When this has been done, check that you have the correct amount of insulin in the syringe.  The correct dose of insulin can be assured if you measure from the needle end, or "0" on the syringe barrel, to the end of the plunger nearest the needle.

                Injecting the Insulin

The steps to follow for injecting insulin are:

1)       Hold the syringe in your right hand (switch hands if you are left-handed).

2)       Have someone hold your cat while you pick up a fold of skin from somewhere along your cat's back with your free hand (pick up a different spot each day).

3)       Quickly push the very sharp, very thin needle through your cat's skin.  This should be easy and painless.  However, take care to push the needle through only one layer of skin and not into your finger or through two layers of skin.  The latter will result in injecting the insulin onto your cat's haircoat or onto the floor.

Proper subcutaneous injection techniques

4)       To inject the insulin, place your thumb on the plunger and push it all the way into the syringe barrel.

5)       Withdraw the needle from your cat's skin.  Immediately place the needle/syringe into the sharp’s container.  Stroke your cat to reward it for sitting quietly.

It is neither necessary nor desirable to swab the skin with alcohol to "sterilize" it.  There are four reasons:

1)       Due to the nature of the thick hair coat and the type of bacteria that live near the skin of cats, brief swabbing with alcohol or any other antiseptic is not effective. 

2)       Because a small amount of alcohol can be carried through the skin by the needle, it may actually carry bacteria with it into the skin. 

3)       The sting caused by the alcohol can make your cat dislike the injections. 

4)       If you have accidentally injected the insulin on the surface of the skin, you will not know it.  If you do not use alcohol and the skin or hair is wet following an injection, the injection was not done properly.

Many people are initially fearful of giving insulin injections.  If this is your initial reaction, consider these points. 

1)        Insulin does not cause pain when it is injected. 

2)        The injections are made with very tiny needles that your cat hardly feels. 

3)        The injections are given just under the skin in areas in which it is almost impossible to cause damage to any vital organ.  Please do not decide whether to treat your cat with insulin until we have demonstrated the injection technique.  You will be pleasantly surprised at how easy it is.

Although the above procedures may at first seem complicated and somewhat overwhelming, they will very quickly become second nature.  Your cat will soon learn that once or twice each day it has to sit still for a few minutes.  In most cases, a reward of stroking results in a fully cooperative cat that eventually may not even need to be held.

Is continual or periodic monitoring needed?

Because a cat's need for insulin can change over time, and because some cats may experience "spontaneous remission", it is extremely important that your cat's progress be checked on a regular basis.  Monitoring is a joint project on which owners and veterinarians must work together. Cats that have experienced a remission are at increased risk for becoming diabetic again, so monitoring in these cats is also important, despite the fact that they no longer require insulin therapy.

               Home Monitoring

First, you need to be constantly aware of your cat's appetite, weight, water consumption, and urine output.  You should be feeding a constant amount of food each day, which will allow you to be aware of days that your cat does not eat, all of it or is unusually hungry after the feeding.  You should weigh your cat at least once monthly.  It is best to use the same scales each time.  A baby scale works well for this. 

You should develop a way to measure water consumption.  The average 10-pound (4.5-kg) cat should drink no more than 7 1/2 oz. (225 ml) of water per 24 hours.  Since this is highly variable from one cat to another, keeping a record of your cat's water consumption for a few weeks will allow you to establish what is normal for your cat.  Another way to measure water consumption is based on the number of times it drinks each day.  When properly regulated, it should drink no more than four times per day.  If this is exceeded, you should take steps to make an actual measurement.

Urine output can be measured by determining the amount of litter that is scooped out of the litter box.  This is a little less accurate if you have more than one cat that uses the litter box, but it can still be meaningful.  The best way to measure litter is to use a clumping litter and scoop it into a sealable container.  After a few weeks you will be able to know the normal rate at which the jar fills.  Too rapid filling will indicate that your cat's urine production has increased.

Keeping a daily diary, calendar or spreadsheet of your cat's weight, food intake, water intake, urine output and the timing of each insulin injection will help you feel comfortable and confident in your pet's progress, and will be very helpful for the veterinarian to assess at each checkup. Any significant change in your cat's food intake, weight, water intake, or urine output is an indicator that the diabetes is not well controlled.  We should see the cat at that time for blood testing

               Monitoring of Blood Glucose

Determining the level of glucose in the blood is the most accurate means of monitoring.  This should be done about every 3-4 months if your cat seems to be well regulated.  It should also be done at any time the clinical signs of diabetes are present.

Timing is important when the blood glucose is determined.  Since eating will elevate the blood sugar for several hours, it is best to test the blood at least 6 hours after eating.  When testing the blood we want to know the highest and lowest glucose readings for the day.  The highest reading should occur just before an injection of insulin is given.  The lowest should occur at the time of peak insulin effect.  This is usually 5-8 hours after an insulin injection, but it should have been determined during the initial regulation process.  Therefore, the proper procedure is as follows:

1)       Feed your cat its normal morning meal then bring it to hospital immediately.  If you cannot get it to the hospital within 30 minutes, do not feed it.  In that situation, bring its food with you.

2)       Bring your cat to the hospital early in the morning without giving it insulin.

3)       A blood sample will be taken immediately, then we will give insulin and feed your cat if it did not eat at home.

4)       A second blood sample will be taken at the time of peak insulin effect.

If your cat gets excited or very nervous when riding in the car or being in the hospital, the glucose readings will be falsely elevated.  If this occurs, it is best to admit your cat to the hospital the morning (or afternoon) before testing so it can settle down for testing the next day.  Otherwise, the tests give us limited information.

Does hypoglycemia occur in cats?

Hypoglycemia means low blood sugar.  If it is below 40 mg/dl (2.2 mmol/L), it can be life-threatening.  Hypoglycemia occurs under three conditions:

1) If the insulin dose is too high.  Although most cats will require the same dose of insulin for long periods of time, it is possible for the cat's insulin requirements to change.  However, the most common causes for change are a reduction in food intake and an increase in exercise or activity.  The reason for feeding before the insulin injection is so you can know when the appetite changes.  If your cat does not eat, skip that dose of insulin.  If only half of the food is eaten just give a half dose of insulin.  Always remember that it is better for the blood sugar to be too high than too low.

2) If too much insulin is given.  This can occur because the insulin was not properly measured in the syringe or because two doses were given.  You may forget that you gave it and repeat it, or two people in the family may each give a dose.  A chart to record insulin administration will help to prevent the cat being treated twice.

3) If your cat has a spontaneous remission of the diabetes.  This is a poorly understood phenomenon, but it definitely occurs in many cats.  They can be diabetic and on treatment for many months, then suddenly no longer be diabetic.  Since this is not predictable and happens quite suddenly, a hypoglycemic crisis ("insulin shock") is usually the first indication. 

The most likely time that a cat will become hypoglycemic is the time of peak insulin effect (5-8 hours after an insulin injection).  When the blood glucose is only mildly low, the cat will be very tired and unresponsive.  You may call it and get no response.  Within a few hours, the blood glucose will rise, and your cat will return to normal.  Since many cats sleep a lot during the day, this important sign is easily missed.  Watch for it; it is the first sign of impending problems.  If you see it, please bring in your cat for blood testing.

If your cat is slow to recover from this period of lethargy, you should give it corn syrup (1 tablespoon by mouth) or feed one packet of a semi-moist cat food.  If there is no response in 15 minutes, repeat the corn syrup or the semi-moist food.  If there is still no response, contact us immediately for further instructions.  (Note: Diabetic cats should not be fed semi-moist foods except for this situation.)

If severe hypoglycemia occurs, a cat will have seizures or lose consciousness.  This is an emergency that can only be reversed with intravenous administration of glucose.  If it occurs during office hours, come in immediately.  If it occurs at night or on the weekend, call our emergency phone number for instructions.

Tell me more about spontaneous remission.

This is a poorly understood phenomenon that only happens in a few cats.  Unfortunately, it can happen rather suddenly so a hypoglycemic crisis may be created when the normal amount of insulin is given.  When it occurs, the cat may be normal for a few weeks or for many months.  However, diabetes will almost always return.  Therefore, you should watch for the typical signs of diabetes then contact us for insulin instructions.

Prognosis
Cats whose glucose levels are difficult to regulate or who require progressively large doses of insulin may require additional diagnostics to eliminate other concurrent or underlying diseases. Overall, cats with diabetes can be medically managed, and if they are stabilized, can live very happy and rewarding lives for years.

For after hours emergencies, please call the Oakland Veterinary Emergency/Critical Care at 248-334-6877. 

Additional resources:
AAFP Health Series: Diabetes
Caring For Your Diabetic Cat Video Series
International Cat Care Cat Health Series: Diabetes mellitus
Felinediabetes.com
My Cat Has Diabetes
Pet-Diabetes.com

How do I know if my cat has high blood pressure?

This is Kitty - why is she falling?

Does this cat look like she has high blood pressure? It's hard to tell from the outside, so routine testing, or "screening" is usually the best way to tell.

Most of the time, when we diagnose cats with high blood pressure, their owner has no specific complaints about their cat's health or behavior. That is because most of the negative effects of high blood pressure in cats are subtle, and act internally before outward signs are seen.

One of the most common causes of sudden blindness in cats is high blood pressure. This is because the tiny blood vessels are put under a lot of strain when a cat has chronic high pressure. This can cause the vessels to rupture or break and small areas of the retina lose blood supply. Once the blood supply is gone, small lesions or detachments form, giving your cat spotty vision. If this goes on for long enough, the entire retina can detach and cause complete blindness.

Fortunately, if high blood pressure is caught early, before too much retinal damage has been done, the lesions can heal, with treatment.

This particular cat was brought in to have an exam because she was wobbly and had started falling off a chest of drawers where she liked to sleep. The only thing that was found on her exam was that she had high blood pressure and some changes to the retina:

So, that's one problem on her list - but is her high blood pressure making her fall?

Sometimes, when a cat has high blood pressure, it is due to the presence of another disease, such as kidney disease, or hyperthyroid disease. In fact, 61% percent of cats with chronic renal failure and 87% of cats with hyperthyroidism have high blood pressure, according to research (citation below).

For Kitty, we took a blood sample to test for kidney disease and hyperthyroid disease. We discovered that Kitty did have some mild changes to her kidneys, too. We started blood pressure medication for Kitty, and when she came in to have her pressure rechecked, her owner told us that she was a changed cat! She had significantly improved, and was no longer wobbly or falling off her favorite sleeping spot.

High blood pressure can cause signs that owners can note, but again, most people only recognize that there was a problem after their cat's high blood pressure is being treated. We hear comments like: "Fluffy is so much less cranky!" or "Callie's appetite is so much better!" or "Smokey seems so much less restless and has stopped crying at night!" when people come in for their blood pressure rechecks.

Other symptoms of high blood pressure (besides blindness and retinal detatchment) include:

• Seizures
• Circling/disorientation
• Dilated pupils
• Hemmorrhage (bleeding) of the eye or nose
• Blood and/or protein in the urine
• Abnormal kidneys
• Heart murmur
• Weakness
• Signs of thyroid disease

If you think your cat may have high blood pressure, or if your cat is over the age of 7 years and you would like your cat screened for high blood pressure, you may want to consider participating in a current high blood pressure study that is being run. For more information about the study, visit www.mycatcanhelp.com or read more about it on our blog at "Feline Hypertension: What you need to know!"

J Vet Intern Med. 1990 Mar-Apr;4(2):58-62. Hypertension in cats with chronic renal failure or hyperthyroidism.

Kobayashi DL¹, Peterson ME, Graves TK, Lesser M, Nichols CE.