Two weeks ago, Mr. Brown, of Woodland Road, Hinckley, brought his 18 year old cat – “Holly” – to see me. He and his wife had prepared themselves for the worst – they did not expect Holly to be returning home.

They had noticed that Holly’s sight had been deteriorating over the previous 3 months, and she now appeared completely blind. However, on top of this problem, she had suddenly become very lethargic and subdued. She seemed to be very distant and “vacant” – not really aware of what was going on around her. Over the past few days Holly had lost her appetite, and was losing weight rapidly.

In a cat of her age, it was a reasonable assumption to make that she had probably come to the end of the road.

I examined her eyes to find the cause of her blindness, and discovered that she had haemorrhages in her retinas – the back part of the eye. This is most commonly caused by high blood pressure (hypertension). She also had a heart murmur – another frequent finding in hypertension. Her depressed mental state could also have been explained by hypertension, as the elevated blood pressure can cause haemorrhages in the brain, too. These can result in anything from odd behaviour to seizures and coma.

I checked Holly’s blood pressure and found that it was dramatically elevated. This confirmed my suspicions. The next question was what had caused this?

In man, 95% of cases of hypertension are classed as “essential hypertension”. This means that no obvious cause can be identified (though genetics and lifestyle may play a part).

In cats, however, only 5% of cases fall into this category. The majority of cases of hypertension are the result of underlying illnesses – usually overactive thyroid glands, or chronic kidney disease. Thus, we always do blood tests for these diseases when a cat has high blood pressure. If the cat has one of these diseases, it is vital to treat the disease, and not just the high blood pressure.

In Holly’s case, however, the blood tests were normal. She therefore fell into the 5% group where the cause of her hypertension was unknown.

Holly was put onto a human drug – amlodipine – to reduce her blood pressure. After a week, Holly returned to be re-assessed. This was “D-Day”, as if she was no better, we had agreed to put her to sleep.

Holly, however, had obviously decided that her 9 lives were not up yet. She had made a dramatic improvement and was eating well, bright, lively and had gained a pound in weight. Her blood pressure was now back to normal.

Her sight had not returned – unfortunately, the eyes are extremely sensitive to raised blood pressure, and sight is rarely restored once lost. Despite this, she was so used to her home environment that she was coping well, and was even going out in the garden again! So, whilst her sight may be going, Holly has decided that the rest of her is definitely staying – for the meantime anyway!

By Geraldine Young BVSc CertSAM MRCVS

Back to "Interesting Cases"

If you wish to print or save this page it is available in PDF format here