What is it?
A Cat Bite Abscess, or CBA, is a common result of cats fighting. Cats' mouths and claws contain a range of unpleasant bacteria, and when fighting they insert these bugs under the skin of their adversary. As the bacteria grow, they form a pouch of dead and dying tissue, bacteria and white blood cells - pus. This pus-filled pocket is an abscess.
What causes it?
As the name suggests, a CBA is most commonly due to a bite from another cat - because cat teeth are long and pointed, and easily penetrate the skin, leaving bacteria behind. Because the teeth are so sharp, and cats heal so well, often the skin will close over and heal, leaving infection inside. The bacteria attack the local cells, and the immune system fights back, building up pus inside a cavity under the skin.
What cats are at risk?
All cats are potentially at risk if they ever interact with another cat! It's less common in indoor-only cats, who fight less frequently, but only a cat who never meets other cats is safe.
What are the symptoms?
As the abscess grows, it becomes painful, however, the majority of the symptoms are due to the infection. Cats with a CBA are often lethargic, off their food, and may have a temperature. They'll often have increased thirst, and may sometimes vomit as well. The site of the abscess, meanwhile, will be painful, swollen and hot. Eventually, it will burst, and thick cream, yellow or cream pus, often mixed with blood, will ooze out.
How is it diagnosed?
Clinical examination alone is usually sufficient; then the vet will use a needle or a scalpel blade to lance it, to determine whether there is pus inside.
How can it be treated or managed?
The most important factor in managing a CBA is to drain it - antibiotics alone are unlikely to resolve the abscess, the dead tissue needs to be out. The normal way to achieve this is for the vet to lance the abscess with a large-gauge needle to a scalpel blade, and then wash out the cavity. Normally, once the abscess has burst or been drained, the cat will start to feel better almost immediately; however, it may be appropriate to use painkillers or anti-inflammatories and antibiotics to encourage it to resolve faster.
Can it be prevented?
Only by preventing cats from fighting - and cats who go outside will, occasionally, fight. However, neutering cats will often reduce their aggression and therefore reduce the risk of a fight, and thus a CBA.