Cats’ mouths are disgusting places. Let’s face it, they don’t brush their teeth, they eat all sorts of small furry and feathery things and they lick themselves….all over…. So it’s no wonder that when a cat bites another cat, a lot of the time, the poor victim ends up with a very stinky, very sore cat bite abscess. These are very common in veterinary practice so here we’ll take a look at why they happen and how they are treated. 

A bacterial paradise

Because of the habits listed above, it’s no surprise that the mouths of our feline friends are alive with all sorts of bacteria. Studies have shown hundreds of species of bacteria residing in the oral cavity of even healthy cats; but actually this situation isn’t too dissimilar to our own mouths. However, the actual amount of bacteria present is often much higher in cats. There is also a difference in the actual species found, with one of the nastiest culprits in cats, Pasteurella multocida not being found in humans. This bacterium is the most common bug found in cat bite abscesses.

How cat bite abscesses occur

Cats are very territorial animals by nature, so it’s not unusual for fights to occur when paths cross. If one cat bites another cat to the point that the skin is damaged, the action of the bite and the fact that their canine teeth are long and pointed, means that the oral bacteria are actually injected into the skin. Typically, the actual tooth wounds are small and will scab over fairly quickly. But under the surface, the bacteria can take hold; and the cat’s immune system has to rally to fight off the infection. The pus we see in cat bite abscesses actually comes from dead white blood cells of the immune system combined with bacteria. And as it’s produced, it will cause the area to swell, forming an abscess. 

What are the symptoms of a cat bite abscess?

The most obvious symptom is a soft, fluctuant swelling covered by reddened skin, usually with hair loss and often with a scab or thin area of skin on top. The area will be painful to touch and if on a limb, the cat is likely to be lame. In many cases, the cat will also be quieter than normal. They may be off their food, especially if they are running a fever. The symptoms can appear fairly quickly and the owner may not be aware of a fight or bite having occurred. In fact, many owners present their cat concerned they may have been hit by a car or have a fractured leg, when actually, there is a cat bite abscess brewing. 

Diagnosis is often fairly obvious; but if in doubt, a needle can be put into the swelling and some of the contents removed, to prove whether it’s pus. If there is a more diffuse swelling, say, of a limb and no scabs to be found, it would be prudent to arrange an x-ray to rule out these other more serious causes. 

How do we treat a cat bite abscess?

The key to treating a cat bite abscess is for us to establish drainage. Often, this is done either by the cat licking the area or through the pressure of the abscess alone, causing it to burst. But if not, we need to lance it. Lancing may be able to be done conscious, especially if it just means removing a scab; but for a thorough job, local anaesthetic or sedation may be required. This means the abscess cavity can be properly flushed with antiseptic solution after drainage of the pus. 

Abscesses are painful so it’s important to provide pain relief for a few days whilst the abscess heals. This is usually in the form of a liquid preparation of anti-inflammatory which is given once a day on food. It is vital that you never give any human medications to cats without veterinary advice as some drugs, such as paracetamol, are highly toxic. 

It also makes sense to give antibiotics as there is clearly a focus of infection; though there is an argument that if the abscess is lanced and all debris cleaned out, antibiotics shouldn’t be necessary. Many vets will still administer them; either in the form of oral capsules, or a longer acting antibiotic injection, both of which are effective against Pasteurella multocida.

Generally speaking, cats are very good at healing 

It often doesn’t take long for the site of the abscess to be practically invisible. Occasionally, if the wound left from a burst abscess is large, surgery may be required to help close the area. 

In rare cases, cat bite abscesses can come with complications, especially if the abscess is over a joint. Septic arthritis is when infection sets up inside a joint and destroys the normal tissues within. It is incredibly painful and can be very difficult to treat. Some viruses such as Feline Immunodeficiency Virus (FIV) and Feline Leukaemia Virus (FeLV) can also be passed on through bite wounds.

Preventing cat bite abscesses

Unless a cat lives purely indoors and is the only cat in the household, preventing cat bite abscesses entirely is nearly impossible. Most cat fights will be over territory. And as entire male cats are much more likely to roam in search of females, they are more prone to being involved in fights and developing abscesses. Therefore, this risk can be reduced by neutering them before letting them outside.

Cat bites in humans

It is worth mentioning that cat bites and severe scratches in humans can be very dangerous. If you are bitten by a cat and the skin is punctured, always seek medical advice as soon as possible and clean the wound thoroughly under running water.

In general, although cat bite abscesses can appear fairly dramatic and can make even the toughest cat pretty miserable, most can be treated quickly and easily with a visit to your vet. It helps to have a strong stomach when dealing with them but your cat will thank you for it!

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