Mary Allen
Thanks to today’s care – both nutritional and medical – it is not uncommon for domestic cats in human care to achieve a life expectancy of 20 years or even more.
Nevertheless, a not inconsiderable proportion of the cat population in old age suffers from most chronic diseases – above all the so-called chronic renal insufficiency in cats (CRF).
In the following text I would first like to explain to you what is actually hidden behind this term, then how and by what means you can recognize it and what a promising treatment can look like.
So What Does it Mean? Kidney Failure in Cats?
Viewed soberly, it describes a functional disorder of the organ – here the kidneys, of which every mammal has two pieces.
The main function of the kidneys is the detoxification of every organism. You have to imagine that at any time of life waste products accumulate in the body’s circulation. So that this ‘waste’ does not accumulate in the body, the kidneys are integrated into every bloodstream. They act as a real filter – similar to a fishing net. Substances that would be toxic to the organism in the long term (we are talking about so-called ‘urinary substances’ here) are filtered out of the bloodstream and temporarily stored together with water in the urinary bladder – if it is sufficiently full, it is emptied to the outside.
At the same time, it is important to keep important substances (above all the vital proteins) in the bloodstream and protect them from being filtered out.
Of course, the kidneys also have other ‘secondary tasks’, which include, for example, the production of the blood-forming hormone erythropoietin (commonly known as EPO). It became famous for decades of doping abuse in professional sports. Especially used in cycling to increase performance because it leads to a significantly improved oxygen transport in the blood. If the deficiency persists, on the other hand, kidney failure usually leads to more or less pronounced anemia [anemia].
These and other functions are disturbed in the case of renal insufficiency. Depending on the degree of the disorder or impairment of the individual function, patients can show various symptoms that justify suspicion.
What are the Symptoms of Kidney Failure in Cats?
By far the most common symptom with which affected patients are presented in the practice consultation is a usually significantly increased fluid intake – at the same time, large amounts of urine are passed. Through this reflex mechanism, the organism tries to dilute the accumulating waste products through massive flushing and at the same time flush them out via the impaired kidneys – true to the motto ‘a lot helps a lot… unfortunately that’s not the case.
This key symptom can be observed quite impressively in indoor cats – how they drink large amounts of water, similar to a continuous-flow heater, and then excrete it again shortly afterward.
In outdoor cats, on the other hand, this symptom often goes unnoticed for a long time. This can possibly lead to a poorer prognosis since the treatment may not be started until later.
Many kidney patients lose weight very quickly and show a shaggy, unkempt coat. They often seem powerless and withdraw.
If the urinary substances accumulate in the body in advanced stages, they are deposited proportionately in all mucous membranes – for example in the mouth and throat area.
You can smell these deposits very clearly – it is not putrid like e.g. with tooth problems but downright pungent and smells of urea and ammonia – i.e. like urine.
For this reason, the affected patients at this stage feel really ‘sick’ – this is also the reason why kidney patients often have so little appetite and also throw up significantly more often – whether with a full or empty stomach.
My Cat Has Kidney Failure. What Now?
If there is a corresponding preliminary report with suitable symptoms (even if only partially), further diagnostics is the method of choice. It consists of a blood test and possibly an additional blood pressure measurement.
When examining the blood parameters, the focus is on measuring the urinary substances – if they are too high, conclusions can be drawn from them and, if necessary, a cautious prognosis can be made.
In the case of a kidney profile, the so-called SDMA corresponds to the early detection value, which usually moves out of the reference range earlier than the parameters ‘urea’ and ‘creatinine’, which have been established for decades, show.
The phosphate value also contributes to the prognosis, since on the one hand it should also be excreted in the urine, and on the other hand, it contributes significantly to the development of nausea at the right concentration.
With the so-called UPC value, a urine sample can be used to determine how much protein is lost through the kidneys.
Determining blood pressure brings added diagnostic value since the relevant findings can be used to quickly and specifically intervene to improve the filtration rate again.
The therapy scheme is based on several pillars, which are sometimes partially or fully applied depending on the degree and condition of the patient:
Pillar 1 represents infusion therapy, in which a sterile saline solution is administered to the patient daily to flush the kidneys and dilute the urinary substances – usually used in advanced stages when the patient drinks too little.
Pillar 2 deals with lowering blood pressure so that the kidneys have more time to filter out toxins. This is done with so-called ACE inhibitors (e.g. benazepril), which slightly expand the diameter of the blood vessels and thus slow down the blood flow. A significantly newer possibility is the use of tartans such as the active ingredient ‘telmisartan’, which also prevents the loss of proteins through the kidneys.
Pillar 3 consists of a diet that is as low in protein as possible (little raw protein) – this corresponds to a significant reduction in the proportion of meat in the feed. Even if this sounds illogical for a carnivore like a cat, this is an important building material because the waste product ‘urea’ is produced when the proteins consumed are processed. However, since this cannot be filtered out of the bloodstream in the case of renal insufficiency, a meat-heavy diet then acts as a fire accelerator. The biggest problem, however, is the acceptance of the diet food, which is unfortunately often scorned because the low to no crude protein also lacks many flavor carriers.
Feeding with so-called wet or moist food is always preferable to dry food in diagnosed renal insufficiency in order to promote the absorption of liquid… of course only if the patient accepts it, because “starvation must not be an option”.
Pillar 4 are phosphate inhibitors or binders. These preparations are administered orally when the excretion of phosphate via the kidneys is no longer guaranteed and it can be measured in the blood at correspondingly high levels. The binding can significantly improve the excretion rate of the phosphate and the acceptance is usually quite good as long as the patients are still eating well.
Pillar 5 corresponds to homeopathy. In addition to the preparation ‘Rene’s Viscum, the so-called SUC protocol with complex remedies should be mentioned here. This is combination therapy with Solidago + ubiquinone + coenzymes. As a rule, the protocol is used as a supplement.
What is the Prognosis for Renal Failure in Cats?
In contrast to chronic renal insufficiency, the chances of recovery in the acute form are significantly worse. However, this occurs mainly through poisoning with antifreeze or lilies and can affect any age.
As the name suggests, their course is usually much more dramatic and can lead to death within a few days or even hours – unfortunately even under therapy.
However, an acute insufficiency of the kidneys can sometimes be better regenerated than the much more common chronic course… provided the treatment was really started very early.
Finally, I would like to point out that if your kitten shows several or even just one of the symptoms described above, please see your veterinarian during the next consultation.
From the age of about 7 years, in my opinion, it also makes sense to have a blood test on your cat once a year – just so that you don’t miss anything, because unfortunately, cats are world champions at hiding symptoms. Therefore, if in doubt, please do not wait long and waste important time by observing.