When your sick cat receives a diagnosis of ‘liver disease’, it may feel like there’s a firm explanation about what’s wrong with your fur-friend. However, what many owners don’t realize is that liver problems come in all shapes and sizes.
Saying a cat has ‘liver disease’ is a bit like saying she has ‘skin disease’, in that it refers to where the issue lies rather than giving a specific diagnosis.
Think of it this way. If your cat has sore skin this could be due to parasites, allergy, sun damage, bacterial infections or trauma. Likewise liver disease in cats can be down to liver shunts, fat infiltration, bacterial infections, or toxin damage (to give just a few examples). All of this matters, because the treatment will be different depending on the actual underlying cause of the liver problem.
A physical examination and bloodwork help the vet understand the cat’s ill health is down to their liver. What’s trickier is to identify ‘why’ the cat has liver disease.
The tools your vet is most likely to use include ultrasound, and biopsy.
- Ultrasound: Gives a grayscale picture of the liver and helps the vet identify unexpected solid or fluid-filled areas, and abnormal blood vessels.
- Biopsy: This involves harvesting a sample of cells or a piece of tissue, which is then sent away for analysis. It’s usually a biopsy (but not always) which enables the vet to label the condition with a specific diagnosis.
But additional tests may be required such as specialized blood tests, x-rays, or an MRI scan.
So what sort of causes is the vet investigating? Let’s take a look.
#1: Liver Shunts
In kittens and young cats, liver shunts top the list of common causes of liver malfunction. The ‘shunt’ is a blood vessel that bypasses the liver, which is present in the fetus but is supposed to shut down after the kitten is born.
However, in some cats the shunt remains open; blood bypasses the liver, missing out on its wonderful detoxing properties. The result is a cat that is poisoned by her own waste products and becomes sick.
In the short term the symptoms can be controlled with antibiotics (metronidazole) and lactulose; whilst in the long term corrective surgery to tie-off the blood vessel is the gold standard.
#2: Bacterial Infections
Cats have a quirky problem with how the gall bladder is plumbed into the bowel and liver. Long story short, the bile duct can act as a super-highway for bacteria to pass in the wrong direction from the gut up into the liver, setting up infection.
This is a common problem, which often responds well to antibiotics and supportive care.
#3: Inflammatory Liver Disease
Alternatively, the liver can become flooded with inflammatory cells. The exact mechanism for this is not clear, but it may be down to an over-active immune system. Whilst the symptoms are similar to those of a bacterial hepatitis, the treatment is different because high doses of steroids are needed to settle down the inflammation.
#4: Fat Deposits
It is dangerous to put a cat on a crash, starvation diet because a starved cat gets energy from her fat supplies, which in turn flood the liver with fat. When active liver tissue is swamped with fat, the liver can no longer function and goes into liver failure.
When fatty liver disease (hepatic lipidosis) does happen, the cat needs intensive care and force-feeding, in order to switch off harvesting energy from fat and clean out the liver.
#5: Toxic Damage
Most human medications are toxic to cats. This is because the cat’s unique metabolism lacks many of the chemical pathways present in other species, which break down harmful drugs. This makes the liver, with its large blood supply, especially vulnerable to toxic damage from medication or other toxic substances.
Poisoning is especially dangerous for cats and often the damage is irreversible, meaning the best that can be hoped for is to give the cat supportive care and a chance to recover.
#6: Liver Tumors
Liver tumors in cats tend to be less aggressive than in dogs. However, cats are prone to lymphoma, a cancer affecting the white blood cells, which seeds to the liver.
In some cases surgery to remove a solitary tumor can be helpful, whilst some forms of lymphoma will respond well to chemotherapy.
#7: A Complication of Disease Elsewhere
The liver has many functions, one of which is policing the blood to remove toxins or bacteria. This means that a problem elsewhere in the body often has a knock-on effect on the liver. Thus elevated liver enzymes don’t always mean it’s the liver that’s sick, it could be a sign the liver is responding to damage elsewhere.
From dental disease to high blood pressure there are any number of problems that give the appearance of liver disease; but happily remove the infected teeth or correct high blood pressure and the liver can return to normal.
The signs tend to be quite general, rather than specific to the liver. If your cat has any of the issues listed below, then a trip to the vet is well worthwhile because something isn’t right.
- Poor appetite
- Increased thirst
- Weight loss
- Yellow gums or skin
- Sickness or diarrhea
- A swollen belly
- Seizures or strange behavior
Of course what really matters to you is whether the cat is going to recover or not. The trouble is, there’s no easy answer to this question. What’s important is the vet works out why the liver is sick and puts an appropriate treatment plan in place.
For some lucky cats it may be a tooth root infection is causing raised liver enzymes, and removing the tooth plus some antibiotic leads to a full recovery. However, other problems can be more serious, and despite best treatment her life is shortened as a result.
But most importantly, if your vet suspects a liver problem and wants to run tests, know this is often vital to recovery. Identifying exactly why your cat’s liver is sick could be key to getting her better again and back on her paws.