|by Johan Schoeman
They say life begins at 40. For cats, middle age could be a complicated affair. These are some of the diseases they could contract, their symptoms and what could be done to treat them.
”I can’t breathe! Quick! Fetch my Pump!”
Feline asthma, like its human equivalent, is characterized by acute attacks of difficult breathing that can be life-threatening if not treated promptly. Siamese cats are particularly prone to this problem. Their airways are hyper-responsive to stimuli like smoke, scented cat litter or hairspray. Many an owner’s social life has been ruined by a cat getting an asthma attack as soon as she applies hairspray and then ends up spending the night with her veterinarian instead of her date!
The treatment is not as successful as in humans, because cats are a touch reluctant to use their pump inhalers. Consequently, anti-inflammatory tabletsor injections are given to suppress the airway responses, along with tablets to dilate the airways.
“Whoa … your breath smells like a dumpster!”
Bad breath (halitosis) with saliva drooling from the cat’s mouth are normally the first signs to alert the cat owner to stomatitis and gingivitis. Opinions differ widely as to the cause of gingivostomatitis in cats, but there is at least general consensus that the condition is triggered by the presence of dental plaque. Certain cat viruses that suppress the immune system like the feline AIDS virus can make patients more susceptible to this condition.
This involves regular cleaning of teeth, which, as one can imagine, is not the favourite pastime of many cat owners. Removal of teeth and sometimes all of the molars (back teeth) is often the only permanent cure. Regular cortisone injections can keep the condition at bay.
“I think I’m going to throw up”
Inflammation of the pancreas or pancreatitis is a condition that is much more common in the cat than previously thought. These patients have no classical clinical signs and normally merely have a history of being chronically unwell. Sometimes they might vomit intermittently, have a rough coat or show some abdominal discomfort. The testing of enzyme levels in the blood is less sensitive than in the dog, adding to the dilemma and the under diagnosis. The wider availability of ultrasound and increasing expertise amongst vets in its use has greatly aided the diagnosis of this enigmatic condition.
“Just scratch me here please … mmm … that’s good!”
Feline atopy, or allergic dermatitis is less common in cats than in dogs. Allergens like pollen and grass seeds can elicit an allergic response that manifests on the skin as redness and severe itchiness. Cats often get a skin reaction that consists of many small little crusts (miliary dermatitis) over the body or generalised scaling or crusting. It should be remembered that it is not only flea allergy that presents with this kind of skin reaction, but also atopy, food allergy, some parasitic infestations and also fungal infections like ringworm. This is because cats display a similar list of symptoms for a wide range of skin diseases.
The best way to manage atopy is to avoid the offending allergen. This is however much easier said than done, because intradermal skin tests are difficult to interpret in the cat and blood tests are not well validated. Fortunately cats respond to corticosteroid therapy quite well.
“Are these pests getting a flea ride?”
Flea bite allergy is arguably the most common complaint for which cats are presented to veterinarians. Patients typically present with a classic skin reaction over the rump at the base of the tail. Severely affected cases have the above-mentioned so-called military dermatitis with small scabs all over the skin. It is believed that this reaction is caused by the presence of a protein in flea saliva. It therefore follows that the magnitude of the reaction is not proportional to the amount of fleas on your pet, but on the degree to which the patient is allergic. Detailed attention should be given to preventing these cats from becoming infested with fleas by treating both the fleas on the cat and the fleas in the environment. An effective way of doing this is to treat it with a flea control product that contains both a flea adulticide (killing adult fleas) and an insect growth regulator(IGR), which breaks the flea life cycle. This must be done according to intervals stipulated for the product, and is generally monthly.
“Oh my heart!”
Hypertrophic cardiomyopathy is the most common form of heart disease in cats. It involves thickening of the muscular walls of the two pumping chambers or ventricles of the heart. Due to the severe thickening of the walls of these chambers, their inside diameters become severely compromised so that they are unable to receive a proper volume of blood from the two atria. Once these chambers are unable to properly fill with blood during the resting phase of the heart cycle, it also follows that they cannot supply enough blood to the body during their contraction phase. A silent killer would be a somewhat harsh way to describe this disease, yet cats with heart disease often only present to veterinarians when it is too late to change the course of the condition significantly.
The first signs that something is amiss could be as catastrophic as thrombosis of both back legs. The “mother thrombus” or blood clot normally sits in the heart in one of the big priming chambers, usually the left atrium. Pieces of the clot become dislodged and travel in the bloodstream down the aorta. Where the aorta forks into the two iliac arteries, which go down each back leg, the small clot lodges like a little saddle that straddles the fork. This shuts off the blood supply to both legs and, if large enough, will paralysethe cat in an instant. About half of these patients with back leg clots also present with concomitant heart failure when they are rushed to the vet. That means that they also have difficulty breathing at the same time and can appear to have a blue tinge to their gums.
These signs are the harbinger of incipient death and must be treated very urgently with oxygen supplementation, drugs to calm the patient and drugs to alleviate the fluid load on the heart. Many cats do survive these thrombotic episodes and should be placed on aspirin therapy just like humans with a propensity for thrombosis. Cats, however, cannot tolerate aspirin daily and should be placed on treatment every third day. The thickened heart muscle can not be made thinner again, but the clinical signs of heart failure such as difficult breathing can be kept at bay with diuretic drugs and certain special cardiac drugs that widen the arteries, enabling the heart to pump much easier, thereby allowing kitty to be spared for another one of its nine lives!
“Not exactly a hip time, this middle age…”
Historically feline hip dysplasia has not been recognised as a clinically important orthopaedic condition. Recent reports however suggest that it is more common than once thought, particularly in some breeds such asMaine Coons and Siamese. Hip joint laxity is thought to be a major factor that allows for damage to the joint cartilage. Clinical signs are often subtle and variable and you may notice slow progressive changes in gaitor intermittent lameness, or even just an unwillingness to play or jump. Diagnosis is based on radiological evaluation of the hip joints.
Conservative management include weight reduction and anti-inflammatory drugs such as meloxicam. “We are not immune…” Since the human AIDS epidemic, there has been a renewed interest in cat AIDS, or Feline immunodeficiency virus (FIV). It was hoped that the cat, with its truncated lifespan, could provide answers for the human equivalent. Whereas the latent period in humans may last decades, cats go through the stages of this infection much quicker and usually develop full-blown AIDS within 5 – 10 years. Unlike its human counterpart, the FIV is not sexually transmitted, but rather by saliva that is inoculated during a bite wound. That is also the reason whey aggressive, non-castrated middle-aged tomcats are the most at risk of contracting this illness. Infection could lead to a few days of fever as the virus multiplies in the blood stream. The viral load drops very quickly and remains non-detectable within the immune cells for many years, where it slowly eats away at the white blood cells of the patient. Once these cells become depleted, the body is unable to fight off any infection and the post mortem report will often read death due to pneumonia or gastroenteritis, whereas the actual cause is AIDS.
“A wee problem …”
Feline interstitial cystitis is one of the most common chronic lower urinary tract disorders of cats. Cats may squat frequently, have bloody urine and urinate in inappropriate places. Your vet will find the urinalysis findings negative, with no crystals or bacteria in the urine. The inside of the bladder wall has characteristic pin point bleedings that can only be viewed with specialized endoscopic equipment. What makes this syndrome remarkable is that there is again an equivalent human interstitial cystitis, an equally frustrating and sometimes incapacitating condition, mostly affecting middle-aged women.
In 50 – 70% of cats that show an initial episode of inappropriate and difficult voiding, the signs will clear within 5-7 days, regardless of treatment. The remainder of cats will display signs indefinitely. Some males might even become obstructed and present with life-threatening signs. This disease is linked to environmental stressors. Stressors are difficult to quantify and differ from cat to cat and may include changes in the environment, weather, food intake, owners’ work schedules and addition of animals to the household. Some patients have a striking increase in severity of signs with every subsequent episode. These are referred to as flares.
Management of the disease include dietary modifications such as changing to canned food and providing a diet that is consistent. One drug that has shown some beneficial effect is a human antidepressant called amitriptyline. Another drug that has shown some promise is pentosan polysulphate which is derived from birch bark and is said to bolster the inner layer of the bladder wall by “coating” is when excreted into the urine and thus protect it from the scalding effect of the urine.
“Mad cat disease? Udder nonsense!”
Feline spongiform encephalopathy was first recognised in 1990 during the bovine spongiform encephalopathy (BSE) or mad cow disease epidemic in the United Kingdom. It is part of a group of naturally occurring transmissible encephalopathies that occur in many species, including sheep and goats, where it is called scrapie. No new cases of FSE have been reported in the UK since 1999. As far as the author is aware the disease has not been reported in South Africa, but remains an interesting disease that should be on the list of any cat showing strange neurological signs such as exaggerated responses to noise or touch, behavioural changes such as increased aggression, unusual way of walking and head carriage and inability to retract claws. It can only be diagnosed by looking at brain tissue under the microscope.
“No, we’re not having fun, gal!”
Cryptococcus neoformans is a fungus and is the most common cause of Nasal cryptococcosis in cats in South Africa. The disease starts in the nasal cavity and nasal sinuses, sometimes spreading to the skin, eyes or central nervous system. The organism is most often associated withpigeon droppings and cats catching pigeons are considered to be at the highest risk of contracting this illness. Infection occurs most commonlyvia inhalation and because the organisms are too large to be inhaled, they settle in the nasal cavity where they cause local inflammation so that these patients often present with a history of longstanding nasal discharge, sneezing, snoring and sometimes local swellings of the nose. Your vet can make a diagnosis by taking a sample from the discharge or the mass and looking at it under the microscope, where they will be able to visualize the organisms.
This includes various expensive antifungal drugs and should be continued for at least two months, with frequent re-assessment after the treatment is over. Although immunosuppressed humans are more prone to this infection, this is not necessarily the case in cats. Immunosuppressed cats are however more likely to be severely infected with easier spread to the brain and the eyes.