Feline diabetes mellitus

Disease overview

Diabetes mellitus is a complex but common disease in cats in which the cat either doesn’t produce or doesn’t properly use insulin. Insulin is a hormone produced in the cat’s pancreas and is responsible for regulating the flow of sugar from the bloodstream into the cells of the body for energy. When insufficient insulin is produced, the cat starts breaking down tissue such as fat to use as an alternative energy source.

Feline Diabetes Mellitus

Possible causes

  • Obesity
  • High levels of sugar in the bloodstream
  • Chronic pancreatitis or other hormonal diseases
  • Drugs such as corticosteroids
  • Exact cause is usually unknown.

How is it diagnosed?

  • Diagnosis is based on a combination of clinical signs, physical examination, urinalysis and blood tests
  • Persistent and abnormally high levels of sugar in the blood and urine or high levels of fructosamine in the blood
  • Tests may need to be repeated over a few days to confirm diagnosis
  • May need additional laboratory tests to check for other diseases.

Clinical signs

  • Increase in urination
  • Compensatory increase in thirst
  • Weight loss
  • Increased appetite
  • Weakness and unsteadiness
  • Poor coat
  • Lethargy
  • Urinary tract infections.

Risk factors

  • Obesity
  • More common in male cats
  • Older age
  • History of chronic pancreatitis or other hormonal diseases
  • History of certain drugs
  • Genetic susceptibility in Burmese breed.

Treatment 

  • Most diabetic cats will need injectable insulin to control blood sugar levels
  • Regular monitoring of glucose levels by a veterinarian to determine insulin dosage during initial stages
  • Diet with moderate to high levels of fibre, high protein and reduced carbohydrates
  • Gradually reducing weight in obese cats
  • Low-stress environment
  • No cure but can be controlled with insulin, exercise and proper nutrition.

Prevention

  • Maintain cat’s healthy weight
  • If your cat is obese, implement a weight loss program
  • Consistently feed your cat a healthy, balanced diet
  • Encourage exercise – even an indoor cat can be active.

Feline upper respiratory tract infections

Disease overview

Viral or bacterial infections of the upper respiratory tract are common in cats. There are several viruses and bacteria which can cause disease of the upper respiratory tract. Vaccines are available for some but not all of them. Transmission is usually by direct or close contact between cats e.g. in sneezed droplets. Therefore cats in crowded environments are at higher risk e.g. boarding facilities and animal shelters.

Feline upper respiratory tract infections

Possible causes include:

Viruses:

  • Feline calicivirus
  • Feline herpesvirus

Bacteria:

  • Chlamydia felis – a common cause of conjunctivitis, especially in young cats
  • Others: Bordetella bronchiseptica, Mycoplasma.

Diagnosis

  • There may be a history of a possible recent exposure to respiratory diseases e.g. a visit to a boarding facility
  • Veterinary physical examination
  • Swabs may be taken from the eyes, nose or throat for testing to identify viruses and bacteria which may be causing the signs.

Clinical signs

  • Sneezing
  • Nasal congestion
  • Discharge from the nose
  • Coughing
  • Ulceration of the lips or the inside of the mouth
  • Redness, swelling, squinting of the eyes
  • Discharge from the eyes
  • Fever
  • Reduced appetite
  • Lethargy
  • Laboured or rapid breathing may indicate pneumonia which is an uncommon but serious potential complication
  • Cats infected with feline herpesvirus become life-long carriers of the virus, and after the initial signs resolve, some will suffer from recurrent problems throughout their lives.

Risk factors

  • Unvaccinated kittens and cats are at an increased risk
  • Cats with suppressed immune systems e.g. feline immunodeficiency virus (FIV) infection
  • Cats in boarding facilities, shelters or visiting cat shows
  • Multi-cat households
  • Stress
  • Poor overall health.

Treatment

  • Antibiotics may be given to cats with viral infections to treat secondary bacterial infections
  • Topical eye ointments may be used if the eyes are affected
  • Chlamydia felis infections require long courses of oral antibiotics and all in-contact cats should also be treated
  • In severe cases hospitalisation may be required
  • Highly palatable food to improve appetite
  • Antiviral medications may help with the signs of feline herpesvirus infection.

Prevention

  • Vaccines are available for feline calicivirus, feline herpesvirus and Chlamydia felis
  • Vaccination cannot prevent infection but it can markedly reduce the severity of the signs
  • Vaccination against feline herpesvirus and feline calicivirus is recommended for all cats, regardless of lifestyle
  • Isolate infected cats from other cats in the household
  • Wash hands to avoid passing infections to an uninfected cat
  • Minimise stress
  • Avoid taking the cat to overcrowded environments.

Feline ringworm

Disease overview

Ringworm isn’t caused by a worm as its name suggests, but is a highly contagious fungus, also known as dermatophytosis, that infects the skin, hair and nails of cats. It can spread to other pets and is zoonotic, which means it can spread to humans, too.

Feline Ringworm

Possible causes

  • The Microsporum canis organism is responsible for most infections in cats, dogs and humans
  • Direct contact with a ringworm-infected pet or human
  • Indirect contact with skin cells or hair of infected pets or humans (e.g. via a brush, or a surface the skin has rubbed on)
  • May occur after flea infestation through bites on the skin
  • Ringworm fungus spores are hardy and can remain infectious in the environment for up to two years.

How is it diagnosed?

  • Patchy, circular areas of hair loss with central red rings
  • Rarely noticed in pets just by looking at the skin
  • More visible on human skin
  • Some types of ringworm fluoresce under ultraviolet light
  • Microscopic examination of affected hairs
  • Culture of the fungus from hair and skin scrapings
  • Important to distinguish from allergic skin diseases.

Clinical signs

The condition does not usually cause itchiness. Signs are variable and can include:

  • Hair loss on skin of the head, ears or legs
  • Claws that are rough, pitted and develop a scaly base.

Pet owners may not be aware of infection of pets for many months. Sometimes it is first diagnosed due to spread of infection to in-contact humans.

Risk factors

  • Kittens less than 1 year old
  • Longhaired cats
  • Cats who are immunosuppressed
  • Rapid spread in shelters or other crowded environments
  • Warm, humid conditions.

Treatment

All in-contact animals must be treated to prevent re-infection

  • Oral, antifungal drugs
  • Medicated shampoos or creams
  • Re-treat over several months
  • Skin cultures rechecked periodically by veterinarian
  • Decontaminate all bedding, baskets, collars, toys, food and water bowls, and grooming tools by washing with disinfectant prescribed by veterinarian
  • Discard items that are impossible to disinfect, such as carpeted cat poles/posts
  • Vacuum floors and carpet to rid house of infected hairs and skin cells
  • Wash hands after bathing or touching an infected pet.

Prevention

  • Routine veterinarian checks for recurrence on pets
  • Check any new cat or dog before bringing them into household.

Feline panleukopenia virus (Feline infectious enteritis)

Disease overview

Feline panleukopenia virus (also known as feline parvovirus or feline infectious enteritis) can cause a severe and often fatal disease in cats. It is thankfully now rare in Australia but cases are still occasionally seen and all cats should be vaccinated against it.

Feline panleukopenia virus (Feline infectious enteritis)

How is it diagnosed?

  • Typical clinical signs
  • Veterinary physical examination
  • Decreased white blood cell count on blood tests (not all cases)
  • Diagnosis is confirmed by faecal tests which can detect the virus.

Clinical signs

Kittens are more susceptible to severe disease but it can be potentially fatal in cats of all ages. Signs may include:

  • Loss of appetite
  • Fever
  • Lethargy
  • Vomiting
  • Diarrhoea, possibly containing blood
  • Dehydration
  • Abdominal pain
  • Sudden death, especially in young kittens
  • If pregnant queens are infected, the virus can spread to the unborn kittens where it can damage the developing brain and result in permanent problems with coordination and balance.

Risk factors

  • Unvaccinated kittens/cats, especially those entering shelters and pounds
  • Kittens are most susceptible to severe clinical signs and death.

Treatment

  • Hospitalisation for supportive care, including fluid therapy and antibiotics to treat secondary bacterial infections
  • Some cats will die despite intensive treatment.

Prevention

  • Vaccination against this virus is highly effective and is recommended for all cats, regardless of lifestyle.

Feline lower urinary tract disease

Disease overview

Feline lower urinary tract disease (FLUTD) is a term used to describe conditions which affect the bladder and/or urethra (the tube between the bladder and the outside of the body). It has several potential causes and results in issues such as bloody urine, frequent urination, inappropriate urination or even urethral obstruction, which is potentially fatal without emergency treatment.

Feline Lower Urinary Tract Disease

Underlying causes include:

  • Bacterial infections – uncommon in cats compared to dogs
  • Urolithiasis (Urinary Stones): urinary stones are rock-hard collections of minerals called “uroliths” that form in the urinary tract of cats. The two most common types are struvite uroliths and calcium oxalate uroliths.
  • Idiopathic cystitis – inflammation of the bladder without a known cause. This is a diagnosis of exclusion, when all other causes have been ruled out.

Diagnosis

  • History from the cat owner and physical examination by the vet
  • Urinalysis – examination of the urine including microscopic examination and tests to rule out bacterial infection
  • Imaging of the bladder and urethra with x-rays and/or ultrasound
  • Blood tests to assess for other issues e.g. kidney disease.

Clinical signs

  • Straining to urinate
  • Increased frequency of urination
  • Blood in the urine
  • Vocalising while urinating
  • Excessive licking of the genital area
  • Urinating outside the litter tray.

Risk factors

  • Neutered cats
  • Obese cats
  • Cats which eat a dry only diet
  • Stress.

Treatment

  • Antibiotics if a bacterial infection is confirmed or suspected
  • Medications or pheromone therapy to reduce stress
  • Urolithiasis: surgery may be required to remove bladder stones. Prescription diets are available to reduce the likelihood or recurrence or can be used to dissolve some but not all types of stones
  • Urethral obstruction:  a life-threatening condition that occurs when the cat’s urethra becomes blocked meaning that the bladder cannot empty. Immediate treatment is essential to relieve the obstruction and prevent kidney failure. This usually involves urinary catheterisation under general anaesthetic to relieve the obstruction and some cats will need to be hospitalised for a period of time for monitoring.

Prevention

  • Reducing stress may reduce the risk
  • Feeding moist rather than dry foods may reduce the risk of recurrence
  • Provide a constant source of clean, fresh water
  • Prescription urinary diets may prevent the recurrence of urinary stones.

Feline hyperthyroidism

Disease overview

Feline hyperthyroidism is caused by excessive concentrations of the thyroid hormone and is the most common endocrine (hormonal) disorder in cats. Thyroid hormone regulates many metabolic processes such as growth, development and energy.

Feline Hyperthyroidism

Possible causes

  • Overproduction by the thyroid gland
  • Result of a benign tumour involving one or both thyroid lobes
  • Result of malignant tumours, but rare in cats.

How is it diagnosed?

  • Clinical signs noticed by pet owner
  • Veterinary physical examination, including palpating neck for enlarged thyroid
  • Thyroid hormone level blood tests
  • Urinalysis
  • Specialist imaging
  • Concurrent diseases such as hypertension, diabetes, cancer, kidney failure and bowel diseases can make diagnosis difficult.

Clinical signs

  • Goitre (enlarged thyroid gland) in many cats
  • Weight loss despite increased appetite
  • Increased thirst
  • Increased urination
  • Behavioural changes such as increased activity or restlessness
  • Increased heart rate
  • Poor coat
  • Intermittent vomiting and diarrhoea.

Risk factors

  • Older cats (rarely affects cats less than 7 years old)
  • Concurrent diagnosis of hypertension (high blood pressure)
  • Any breed, male or female.

Treatment 

Four options:

  1. Medical management (anti-thyroid drugs): requires lifelong medication, usually with tablets
  2. Surgery: can produce a permanent cure, but anaesthetic and surgery risks may be higher than normal unless the disease is initially controlled with medication.
  3. Radioactive iodine therapy: often curative. Requires an injection of I-131 at a specialist hospital and a hospitalisation of 3 to 7 days.
  4. Iodine restricted diets: shown to effectively lower thyroid levels. May be a problem in multi-cat households as the affected cat cannot eat any other food and healthy cats should not eat the iodine-restricted diet. These diets should be used under the direction of a veterinarian.

Prevention

No known methods to prevent the condition.

Feline dental disease

Disease overview

Feline dental disease is one of the most common medical conditions seen by veterinarians. Regular health checks are important to detect signs of dental disease early.

Feline Dental Disease

Possible causes

  • Plaque and tartar accumulation on teeth
  • Gingivitis – inflammation of the gums
  • Periodontal disease – an advanced gum disease which can result in tooth loss
  • Malocclusion (abnormal bite)
  • Tooth resorption – this is a condition which results in the loss of tooth structure, starting with the outer enamel surface, usually at or below the gum line. It is a common and often painful condition.

How is it diagnosed?

  • Signs may be noticed by the pet owner e.g. difficulty chewing/eating, bad breath and weight loss
  • Veterinary physical examination of the mouth
  • Dental x-rays may be performed under anaesthetic to determine the extent of disease.

Clinical signs

  • Inflamed gums (gingivitis) that may bleed easily
  • Visible plaque on the teeth
  • Decreased interest in food
  • Chewing food with discomfort
  • Foul mouth odour
  • Reluctance to eat dry/hard food
  • Excessive drooling
  • Weight loss.

Risk factors

  • Mature, senior and geriatric cats, although younger cats may also develop dental disease
  • Lifelong diet of moist or soft foods
  • Genetic susceptibility to malocclusion or oral resorptive lesions in some breeds.

Treatment 

  • Dental scaling and polishing under anaesthetic is often required to remove tartar and plaque
  • Tooth extractions, if necessary
  • Antibiotics may be used if infection is present in the mouth.

Prevention

  • Regular dental check-ups by a veterinarian
  • Some cats may allow owners to brush their teeth (with specially designed soft brushes and toothpaste)
  • Your vet may recommend a prescription diet with a specially designed kibble to help reduce tartar build-up or dental treats. Look for products with VOHC approval.
  • Dental scaling and polishing early in the disease may prevent progression and severe disease.

Feline hypertension

Disease overview

Hypertension (high blood pressure) is fairly common and potentially a severe threat to a cat’s health. The condition can occur by itself (primary hypertension) or it can also indicate the presence of underlying diseases (secondary hypertension). Hypertension occurs most commonly in older cats and can cause damage to a cat’s kidneys, eyes, heart and brain.

Feline Hypertension

Possible causes

  • Primary hypertension: not associated with other diseases and has no discernible cause; rare in cats and may be genetic
  • Secondary hypertension: accounts for 80% of all hypertension in cats and is almost always the consequence of underlying diseases, such as kidney disease and hyperthyroidism
  • Heart conditions and tumours are less frequent causes
  • Some medications may cause a temporary rise in blood pressure.

How is it diagnosed?

  • Blood pressure measurement
  • Clinical signs of underlying diseases (e.g. hyperthyroidism causes weight loss despite increased appetite)
  • Laboratory tests for kidney disease, hyperthyroidism and diabetes.

Clinical signs

  • Usually none for primary hypertension, unless organs are damaged (e.g. sudden onset of blindness).
  • Many for secondary hypertension caused by underlying diseases:
    1. Kidney disease: poor appetite, weight loss, increased drinking and urination, blood in the urine.
    2. Hyperthyroidism: enlarged and palpable thyroid gland, weight loss, increased appetite, hyperactivity, increased drinking and urinating, vomiting.
    3. Heart disease: heart murmurs.

Risk factors

  • Mature, senior and geriatric cats.

Treatment

  • Once diagnosed, treatment is initiated to minimise damage to major organs (eyes, kidneys, brain and heart)
  • Anti-hypertensive medications to lower blood pressure
  • Treatment of underlying disease(s).

Prevention

  • Frequent blood pressure monitoring by veterinarian on annual physical examinations
  • Early detection of any new disease or worsening of any diagnosed disease
  • Healthy, balanced diet
  • Maintain cat’s healthy weight
  • Stress-free home environment.

Feline heart disease

Disease overview

Feline heart disease can be due to an inherited (congenital) condition, or an acquired disorder. Inherited heart disease is relatively rare and can be diagnosed in cats as young as 6 months of age. Acquired heart disease involves changes to the muscles around one or both ventricles of the heart and accounts for the majority of heart disease diagnosed in cats.

Feline Heart Disease

Possible cause

  • Inherited: Genetic mutations and predisposition in some breeds of cats
  • Acquired: Thickening or deterioration of the heart muscle resulting in the inability of the left ventricle to pump blood into the aorta (cardiomyopathy)
  • Underlying diseases such as hypertension (high blood pressure), hyperthyroidism (high level of thyroid hormones secreted in blood) and anaemia (low red blood cell count) can cause or complicate cardiomyopathies.

How is it diagnosed?

  • Clinical signs noticed by pet owner
  • Physical examination including blood pressure measurement and examination with the stethoscope to listen for a heart murmur
  • Laboratory testing, including a blood test to rule out hyperthyroidism
  • Testing such as an ultrasound on the heart (echocardiography), electrocardiography (ECG), and x-rays.

Clinical signs

  • Abnormal heart sounds
  • Abnormal heart rate
  • Weak pulse
  • Difficulty breathing
  • Inability to tolerate exercise or exertion
  • Loss of appetite
  • Lethargy
  • Collapse
  • Bluish discolouration of foot pads and nailbeds
  • Sudden loss of use of hind limbs.

Risk factors

  • Inherited heart problems can be diagnosed by 10 months of age or earlier
  • Acquired heart problems typically occur in mature cats (7-10 years), senior cats (11-14 years) and geriatric cats (15 years +)
  • More frequent in male cats
  • Genetic susceptibility in certain breeds, such as Maine Coons, British and American Shorthairs, Persians and Ragdolls.

Treatment 

  • Treatment of cardiomyopathy may require hospitalisation, diagnosis of cardiomyopathy requires hospitalisation, especially if there is congestive heart failure
  • Oxygen therapy
  • Medications to control the heart rate and treat irregular heartbeats
  • Drugs to control underlying disease such as high blood pressure, or hyperthyroidism
  • Blood thinners to decrease risk of blood clots
  • Quiet environment to minimise stress.

Prevention

  • Low-sodium diet
  • Frequent, ongoing veterinary visits and monitoring of treatments and medications
  • Minimise stress in the environment
  • Limit strenuous activities
  • Some cats can live a relatively normal life, depending on how fast the disease progresses.

Feline epilepsy

Disease overview

Feline epilepsy is a recurring seizure disorder that originates from abnormal brain activity and is the most common cause of brain disorders in cats. Idiopathic epilepsy is a term that means unknown cause (includes genetic or congenital causes) and is the most common diagnosis. Seizures result in a sudden uncontrolled burst of activity with many abnormal signs. Seizures can occur as a single event or as a cluster of seizures over a short time or on a recurring basis every few weeks or months.

Feline Epilepsy

Possible causes

  • Idiopathic (unknown) cause
  • Genetic/congenital
  • Brain tumours
  • Poisoning by toxins, chemicals, rodent bait, overdose of certain drugs
  • Metabolic disorders, such as diabetes, kidney disease or liver disease.

How is it diagnosed?

  • Observations by cat owner during a seizure
  • History essential to veterinary diagnosis
  • Veterinary physical examination
  • Blood tests and urinalysis, imaging of the brain e.g. MRI scan
  • Rule out poisoning, drug overdoses and metabolic disorders
  • Idiopathic (unknown) diagnosis is most common.

Clinical signs

  • Seizures usually last a few seconds to two minutes and recur infrequently, however in severe cases they can go on for longer or recur very regularly.

Partial (mild) seizures may look like:

  • Disorientation, hiding
  • Face muscles, eyelids, whiskers and ears twitching
  • Loud meowing
  • Agitation and nervousness
  • Trembling
  • Staring into distance
  • Stiffness.

Generalised (full) seizures may look like:

  • Collapse
  • Loss of consciousness
  • Convulsions
  • Snapping jaws
  • Foaming at the mouth
  • Panting
  • Loss of control of urinary and faecal functions.

Risk factors

  • Cats of any breed, age or sex
  • Genetics (occurs in family members and litter mates)
  • Access to poisons, chemicals, rodent bait
  • History of head injury
  • Congenital brain deformity in kittens.

Treatment 

  • For partial seizures, talk soothingly and help the cat feel safe until the seizure stops. Be careful as some cats may become unexpectedly aggressive.
  • For generalised seizures make sure the cat is in a safe space (e.g. where it cannot fall from a height, or in to a swimming pool). Do not try to hold the cat or stop the seizure yourself.
  • Seek veterinary help immediately if a seizure lasts longer than 5 minutes, occurs more than two times in 24 hours or begins before the cat has recovered from a previous seizure
  • Initiation of antiepileptic medication(s) if seizures occur frequently
  • Ongoing veterinary visits to monitor medications and general health
  • If a brain tumour is diagnosed, surgery, radiotherapy or chemotherapy may be possible.

Prevention

  • Prevent trauma and injury during a seizure by blocking off stairs and furniture inside, and standing water outside
  • Protect yourself by never putting fingers inside a cat’s mouth during a seizure; the cat will not swallow its tongue.

Feline asthma

Disease overview

Feline asthma is an inflammatory condition of the airways. In response to an irritant or allergen, the airways become narrowed which can result in difficulty breathing, especially when the cat exhales. There is no cure but the condition can usually be managed with medication.

Feline Asthma

Diagnosis

Other causes of respiratory signs must be ruled out e.g. viral/bacterial infections and heart disease. Further investigations may include:

  • A full physical examination by your vet including listening to the heart and lungs with a stethoscope
  • Blood tests
  • X-rays of the chest to look for typical changes in the lungs
  • Samples may be taken from the airways under anaesthetic to be analysed.

Clinical signs

The clinical signs can vary in severity and can be acute (sudden onset) or chronic (persistent) and may include:

  • Coughing and wheezing
  • Laboured/fast breathing
  • Difficulty breathing e.g. open mouth breathing – this suggests a life threatening problem and requires emergency veterinary care.

Risk factors

  • Outdoor cats exposed to pollen, weeds and grass may be at a higher risk
  • Tobacco, fireplace and candle smoke can act as irritants and triggers
  • There may be an inherited component to the disease as some breeds e.g. Siamese, appear to be at a higher risk of asthma.

Treatment

Feline asthma is not curable but usually manageable. Treatment options include:

  • Emergency treatment with oxygen may be required for serious cases
  • Anti-inflammatory drugs to reduce bronchial inflammation – by injection, tablet or inhaler
  • Bronchodilator therapy to open the airways – by injection, tablet or inhaler
  • To administer inhalers to cats a ‘spacer’ device is used (just as in human babies and young children) with a face mask.