Veterinary Medicine for Dogs & Cats
Health Tracking In Cats – Seniors
Seniors
Past about the age of eight years, there are some simple on the spot tests which assist in screening for the more common serious disorders.
Bodyweight – weight loss is a useful indicator of problems like overactive thyroid glands, kidney and bowel disorders.
Urine –the concentration of the urine combined with knowledge about the diet is a
very sensitive indicator especially for kidney performance. It takes about 2 seconds
to measure with a refractometer.
Blood pressure – high blood pressure can occur for several reasons but the commonest is kidney failure, and controlling blood pressure can greatly extend quality of life by reducing heart muscle strain, blood vessel damage in the eye and brain, and slowing kidney failure progression.
Simple blood tests like creatinine and urea – with the HESKA iSTAT handheld pathology machine the results are back in about 2 minutes.
One Of The Common Cat Urinary Tract Problems
In cats bladder and urethral problems are one of the most common reasons for walking in the veterinary door. People always assume, and so did vets for many years, that it is always a “bladder infection”. Well no, generally that only happens when they have age related reduced kidney function, with very dilute urine making a bladder a nice place to live for bacteria. Most bladder and urethral disease commonly occurs in younger animals, because of the very high concentration of the urine that they are able to produce, which is then pushed even higher because of a high dry food intake.
What
This disorder is called Feline Idiopathic Cystitis (FIC-“Idiopathic” means we don't know why). Any urinary tract problem causing inflammation of the bladder and urethra will have similar signs, being straining, frequent small spots of urine, often in places other than a litter tray, and sometimes with blood in the urine. And in the worst case, with boy cats the urethra will block and there will be initially severe pain signs especially on picking up because of severe bladder distension.
Why
FIC happens because the cells that line the lower urinary tract, called urothelium, can have their junctions with one another partially disrupted from a variety of causes. This means bladders and urethras leak and urine gets in contact with tissue that wasn't meant for it. If the urine is high concentration, then the damage is worse. What causes the variation in urine strength? Mostly, if you are a cat, what you eat. Cats evolved in North Africa in fairly arid zones, and their plumbing evolved to meet those requirements. They don't drink beer or wine, or tea or coffee. They drink what they need unless its loaded with calories, and that's all.
A cat eating tinned or sachet food will typically take on 50% more water than a cat on dry food, and so their urine will be more dilute and so less damaging. Cats with FIC problems have about a 4 times higher relapse rate on dry food compared to wet food diets. There are lots of therapeutic dry food diets that are sold to fix bladder problems, usually as acidifying diets to help get rid of something called struvite. Struvite was common in the old days because some of the old diets had high magnesium levels, which is now largely resolved Urine crystals form in most cats, both normal and abnormal, but the crystal level of another kind called calcium oxalate can be greatly increased by acidifying diets.
Another factor with FIC is stress. That's one of the things that creates the leaking of the cells lining the urinary tract. Stress has many contributors, and can be things as banal as frequent diet or kitty litter changes. Having one litter tray and several cats or even several trays but all in the same room. Warfare between cats or between humans in the shared household. Workman or other strangers. Being kept indoors and having a very boring pussy cat life. Being fat. Piddling outside but pussy cat crossing their legs because of all the rain and they don't get to go soon enough. That can have a role in urolith (bladder stone) formation too as the longer urine is retained the higher the stone formation rate.
What To Do About It
Well you probably got the idea by now. The one single factor that you can control in cats with urinary problems and who have high urine concentrations (that's measured by your vet with a simple thing called a refractometer – its not colour) is too abolish dry food intake. There are other contributors, but relentlessly concentrated urine because of a lack of incidental water intake in wet foods is the most identified cause of trouble and the simplest to resolve. Unless your cat is a dry food addict. You avoid that by giving them different food types when they are kittens to avoid the addiction problem. There other tricks like rainwater, running water, fish, beef and chicken stock, progressive trickling water into the dry food etc. Not enough space here.
Treating Lymphoma In The Dog
Lymphoma is a rather common cancer of the lymphatic system with a number of different manifestations in different body parts and different stages. It is most commonly detected as something called multicentric lymphoma where lymph nodes all over the body are enlarged by the rapidly multiplying cancerous lymphocyte cells.
It has a number of other forms like one in the chest called a mediastinal lymphoma which typically shows up from disturbing calcium levels in the blood causing severe urine dilution requiring high water intake, other solitary tumours in places like nasal cavities or single or diffuse invasion of bowel walls. It can also start off as or progress into a skin tumour which looks like dermatitis or large white plaque like lesions all over the body.
Multicentric lymphomas mostly respond well to treatment, but only for buying time rather than cures. This is called remission and is mostly measured in months and occasionally up to 2 years, with a small percentage of certain treatment types producing what can be called a cure. Diagnosis is usually pretty simple, especially with the more aggressive ones, often requiring nothing more than a needle aspiration with the sample being sprayed out on a slide and looked at under a microscope, usually with referral to a pathologist for confirmation.
Staging is a bit more elaborate. When the cancer is so advanced that it is causing sickness signs like weight loss, weakness, high water intake, fever and others, the response to treatment is less reliable. Blood chemistry, urine checking, and imaging of the chest with x-rays and organs like liver, spleen and kidneys with ultrasound will show if the cancer is far advanced. Making those assessments will give you as the owner a better idea as to the expected benefit of treatment and whether it is worth undertaking it at all.
There are also breed disorders like a defective enzyme picked up by a gene test called MDR-1 which may require avoidance of commonly used chemicals like vincristine that are best tested. On top of the up front assessments of diagnosis and staging, tracking how well things like the white cell production is holding up is advised in case the accumulated dosing or frequency of treatment is getting too high.
There are many treatments for lymphoma, with cost being one of the determinants of choice. There are two broad groups, being single agent, that is one drug, in this case adriamycin, otherwise called doxirubin given every 3 weeks 3 to 5 times in all with an expected remission of up to 8 months.
Then there are the multiagent protocols, which are based on the fact that cancer cells will rarely be resistant to several drugs, which will involve a mixture of initially weekly injections with of alternating agents given with daily or several days per week of tablets of chemotherapy drugs and cortisone for generally no less than 8 weeks, and then often a switch to longer inter-treatment intervals of 3 weeks.
Published opinions of the need to continue treatment or use an aftercare therapy called maintenance protocols vary over time according to each protocol. The best remission claims are of 24 months, but this doesn't come with a 100% probability on any treatment type. What this means is treatments change over time.
Referral vets specialising in oncology do a very good job, but the price tags are necessarily high, so generalist vets can help your pets with this problem usually at a lower cost, but not always. The problem is if the vet has to order a single bottle of a drug they have to discard after opening then the bill has to cover the whole drug cost, and some of these drugs are more than a $100 wholesale a bottle.
We try to co-ordinate a few dogs where possible to split the cost on a single bottle to keep charges down when possible. And some dogs get problems like bleeding from the bladder with some chemotherapy, and some get almost parvo like signs or heart failure on adriamycin, so life improvement can't always be guaranteed. Make note the recently publicised drug called ECB-46 wont help with multicentric lymphoma.
Canine and feline lymphoma treatments aren't as aggressive as human protocols, because we try to come out cured. Our pets are just meant to feel better longer. It's palliative therapy, and because they don't know they are dying, they aren't anywhere near stressed as we are.