Tabby all patched up

Remember Tabitha? She was diagnosed with kidney disease earlier this year. After a bit of persuasion she took  to her special diet for failing kidneys with relish, although she misses her weekly fresh rabbit.
This week she had her progress tests. Her potassium levels were fine - diseased kidneys lose potassium - and her phosphorus levels were normal too. If phosphorous gets too high or potassium too low then cats lose their appetite and feel ill.
We were concerned to find that her creatinine levels were creeping up but as they are not affecting her appetite or quality of life we will just monitor her again in 3 months time.
Overall the special low protein, low phosphorous, high potassium kidney diet is keeping her healthy and happy so that she can properly supervise the next patchwork project - and at 16 years of age that's pretty important!

Lily toxicity

Day Lily

All species of lilies are toxic to cats. Indoor cats with little choice in plant munching material are most at risk as they will try any cut flower that comes into the house. 

Any part of the plant – flowers, leaves or stems - is dangerous. Even lily pollen licked off the coat destroys cats’ kidney tubules. 

Lilies proven to poison cats include: Easter Lily, Tiger Lily, Day Lily, Glory Lily, Stargazer Lily, Rubrum Lily, Asian Lily and the Japanese Show Lily

If you see your cat with lily on her coat, in her mouth or in her vomit don’t wait for signs of poisoning. The sooner we get it out of her system and start treatment to protect the kidneys the greater her chance of survival.

Affected cats vomit and are depressed within hours of ingesting lily. Some then seem to recover before starting to show signs of severe kidney failure a day or so later. Others continue vomiting, go off their food and get more and more depressed.

If emptying the stomach and medications to prevent absorption of the toxin are effective, the chance of recovery is excellent.

If your cat absorbs enough toxin to cause damage to her kidneys then her outlook is very poor. It is essential to seek emergency care immediately after ingestion of the lily plant.

Tiger, Tiger sitting tight

Tiger is just on his way home after having his blood pressure checked. He sat quietly while we wrapped a cuff around his arm. He thought the cold gel we put on his wrist for the Doppler probe was the worst part.
Because a cat's pulse is so small we have to amplify it with the Doppler. We pump the cuff up until we cannot hear the pulse and then slowly let the air out until we hear the pulse. At this point we read his blood pressure from the dial.
Tiger has a heart murmur and kidney problems. Heart disease often lowers the blood pressure but kidney failure increases it. Fortunately Tiger's blood pressure is normal.

High blood pressure

Hypertension is the medical term for high blood pressure, a silent killer of older cats.

What causes hypertension in cats?

Hypertension is usually secondary to another disease. Kidney disease is the most common cause of hypertension but cats with adrenal gland tumours or treated for hyperthyroidism also develop high blood pressure at times. Sometimes no underlying cause is found.

Most cats with hypertension are older than 9 years of age.

What are the effects of hypertension?

Hypertension damages all body organs but we notice it most in:

• the eyes. The small vessels in the retina break under pressure. The bleeding detaches the retina and the cat becomes blind.
• the brain. Ruptured blood vessels cause ‘strokes’, fits, twitches or unusual behaviour
• the kidneys. Increased blood pressure damages the delicate filtration system of the kidney.
• the heart. The heart has to work harder to push the blood out into the body and the heart muscle thickens and becomes less efficient. Sometimes the heart goes out of rhythm or we hear a murmur with the stethoscope. Affected cats may show signs of heart failure such as breathlessness, lethargy, weakness or fainting.

How do we detect hypertension?

We measure the blood pressure of all cats over 9 years old as part of the regular seniors’ examination. We also check the blood pressure of all cats with kidney disease or hyperthyroidism, or with any signs of eye, brain or heart disease. 

Most cats tolerate the cat sized cuffs we put on their arms. Some don’t like the feel of the gel or the sound of the amplifier we use to hear the pulse. We try to put them at ease so that we get an accurate reading.

How do we treat hypertension?

A daily dose of amlopidine as a fragment of tablet (Norvasc), or as chicken, fish, cheese or beef flavoured drops to put on the food, brings the blood pressure down rapidly.

After a week on amlopidine we recheck the blood pressure to see if it has come down to normal. If all goes well we recheck it every 3 months. 

Sometimes other medications like benazepril (Fortekor or Vetace) are added in, particularly if we detect kidney disease.

Kidney Failure

Mittens getting the right balance

What do kidneys do?

The kidneys remove waste products from the blood stream, regulate fluid and electrolyte balance, maintain the acid-base balance of the body and remove toxins and drugs. They also help maintain blood pressure and stimulate blood cell production.

What happens when my cats’ kidneys fail?

Signs of kidney failure don’t appear until at least 70% of kidney function is lost. Chronic kidney failure, also known as renal failure, is the end stage of a number of different disease processes rather than a specific condition in its own right.

Kidney damage accumulates for years before we see any signs. Even then the early signs of kidney failure - increased thirst and urine production - are not easily recognised in our feline friends.

You may notice an increasingly wet litter tray if your cat is only indoors. However if you have other cats you may not pick up increased urine production in a single cat. 

Cats often drink from multiple water sources making it difficult to recognise increased  consumption.  

Other signs of kidney failure such as weight loss and poor coat quality are often put down to normal ageing. 

Often the first thing we see is a cat off her food, vomiting, depressed and dehydrated. The kidneys are already badly affected by this stage.

How do we diagnose kidney failure?

We diagnose and stage kidney failure with blood tests for the two waste products, urea and creatinine and a urine analysis to measure the kidneys ability to concentrate urine. We also  check the urine for protein loss or a urinary tract infection.

Tests for other substances like potassium, phosphorus and calcium as well as blood cell counts help us decide on the best course of treatment. 

Could it have been diagnosed earlier?

Because signs of kidney failure and rises in blood urea and creatinine are not evident until significant loss of kidney function has occurred early diagnosis is difficult. However, we strongly recommend at least annual blood and urine tests, as well as regular body weight checks. If urine concentrating ability is deteriorating or the creatinine is trending up we are able to slow down the progression of the disease with a special kidney protective diet. Any weight loss in a cat should be fully investigated.

What treatments are available?

After initial hospitalisation to treat dehydration and electrolyte disturbances, most cats are managed with a diet change and one or two other medications.

• Low protein and phosphorus diets lower the level of waste products in the bloodstream.  Try a few of the ready made kidney diets like Royal Canin renal or Hills k/d to find one your cat likes. Once your cat accepts the diet it must be her sole source of nutrition. Although if renal failure is advanced and your cat’s appetite is poor, any diet that the cat enjoys is acceptable.

• If blood phosphorus levels remain above normal after a few weeks on the special diet we add phosphate binders like Ipakitine to the food. Reducing blood phosphorus makes your cat feel better and slows progression of the disease. 

• Urinary tract infections are common in kidney failure and are treated with antibiotics.

• Cats with renal failure lose potassium in the urine leading to muscle weakness, stiffness, a poor coat and exacerbation of the kidney failure. The special kidney diets contain extra potassium but sometimes we have to add more.

• Severely affected cats need extra fluids. We can teach you to administer      subcutaneous fluids at home to reduce dehydration in advanced cases.

FRESH WATER MUST BE AVAILABLE AT ALL TIMES 

How long can I expect my cat to live?

Unfortunately aged kidneys do not recover. However, we can slow the progress of the disease and improve your cat’s well being with treatment and regular checkups. We check  phosphorous and potassium levels to see if your cat requires supplements and check for urinary tract infections at least every 3 months. This should give your cat a good stretch of high quality, active life.