Dear Most Esteemed and Knowledgeable Kitties:

I was petting my cat and I noticed swelling by the end of her back. I examined the swelling and found a small scab, maybe the size of a pen point. The inflamation is soft. What could this be? Do you think she was bitten by a bee or any other insect?

~Lashonne

Siouxsie: It sounds to us like your kitty has a bite wound that is becoming an abscess.

Thomas: An abscess is an infection caused by a puncture wound, almost always a bite from another cat.  Abscesses are most commonly seen on cats’ heads, necks, shoulders, or rumps and tails. When cats fight, they attack one another’s heads with claws and teeth, resulting in the frontal abscesses. If one of the cats decides to run away, the victor can bite the fleeing cat on the backside, resulting in the abscesses on the rear quarters.

Dahlia: The last night we lived at the farm, the Nasty Orange Barn Cat decided he was going to beat me up. I fought back as best I could, but he was so much bigger than me and there was no way I could win. He bit me on my elbow, and then as I was trying to run away he bit me on the butt! I was so sad. A fine fare-thee-well that was! And I’d never done anything to hurt him …

Thomas: There, there, Dahlia. It’s  all right now. Mama saw you limping on that swollen leg and got you to the vet right away. You’re all better now, and you’re never going to have to see that Nasty Orange Barn Cat again.

Siouxsie: In order to help you understand why we think your cat has an abscess, we should take a moment to explain how abscess symptoms are different from insect sting symptoms. First of all, there’s the issue of location. Abscesses tend to occur on the head, neck, shoulders, or rear end. Insect bites or stings are more commonly seen on the face, head, or inside the mouth–and occasionally on other hairless areas like the paw pads.

Thomas: When an animal is first bitten or stung, you’ll see the symptoms within 20 minutes or so. If you’ve been stung before you know what to look for: Swelling and pain that subsides within about an hour. In some animals or animals that get a lot of stings, an anaphylactic reaction may occur. The most severe type of anaphylactic reaction is when extreme swelling closes the breathing passages, making it very difficult for the animal to get air.

Dahlia: A sting causes a small, hard swelling that almost never has a scab.

Siouxsie: When a cat is bitten, an abscess develops over a couple of days. You’ll see a simple puncture wound–as you described in your letter–on Days 1-2. This puncture wound may be accompanied by a little bit of swelling.

Thomas: The swelling around the puncture wound increases, sometimes quite rapidly, from days 2 through 5. As the fluid accumulates, there will be hair loss around the swollen area, the skin tissue lifts, and an abscess forms in earnest.

Dahlia: Eventually the pus accumulates enough to weaken the skin above it and the abscess ruptures. When the abscess ruptures, it releases purulent material that can range in color and consistency from yellowish gunk that looks like snot to foul-smelling purplish-brown  slime.

Siouxsie: As an abscess develops untreated, a cat will typically start acting sick: lethargic, feverish, perhaps not eating. Depending on the severity of the infection or the cat’s immune response, this will occur to a greater or lesser degree.

Thomas: Bite wounds can be treated before they become abscesses, as long as you detect them early. The typical veterinary treatment forbite that hasn’t developed into an abscess is a round of antibiotics, and home care to keep the wound clean and open.

Dahlia: If a full-blown abscess is present, more complicated veterinary treatment may be required, including surgical cleaning of the wound and installation of drains to allow you to irrigate the abscess and keep it clean as it heals. Also, if the cat has become very sick and is running a high fever, other complications like dehydration can result.

Siouxsie: It certainly is possible to treat puncture wounds at home, but we do recommend a vet visit. Antibiotics can stave off a very severe infection, and if you haven’t had much experience with cat wound care your vet can teach you how to do this properly.

Thomas: Another thing you should know is that you should never bandage a puncture wound. Bandaging gives the bacteria an even better place to grow and multiply and make your cat very ill.

Dahlia: Mama had a friend who had recently adopted her first cat. Apparently the cat came home with an injury on his leg, and the friend bandaged it. A few days later the friend called Mama and said she was worried about her cat because he didn’t seem to be feeling well. Mama went to her house and found one very sick kitty: running a scary fever, third eyelids showing, really dehydrated, and his whole front leg swollen because of an abscess and spreading infection!

Siouxsie: Naturally, Mama rushed the cat to the vet, where they saved his life–and his leg.

Thomas: We need to address another very serious danger that can result from cat bites: the transmission of serious and possibly fatal disease. In addition to the risk of wound infection, cat bites can transmit feline leukemia virus (FeLV),  feline immunodeficiency virus (FIV), or even rabies.

Dahlia: If your cat’s rabies and FeLV vaccinations are up to date, she’s pretty safe from any potential danger. There is a vaccination for FIV, but the American Veterinary Medical Association doesn’t recommend the FIV shot as a core vaccination because it has not been proven effective and also results in false positives on FIV tests.

Siouxsie: Pets that haven’t been vaccinated for rabies may have to be euthanized and tested for rabies. The rabies test requires microscopic examination of brain tissue and is not a test your pet can survive. Some locations will allow unvaccinated bite victims to be quarantined at an animal shelter or veterinarian’s office for six months instead of being instantly euthanized. Read more about rabies quarantine procedures here.

Thomas: Your vet may suggest that your cat have a blood test for FeLV and FIV in six weeks. If your cat got the virus from her bite, it takes about six weeks before an accurate result can be obtained. We’d recommend that you have your vet do this test. If your cat does turn up FeLV or FIV positive, she’ll have to be kept indoors for the rest of her life and you’ll have to monitor her health very closely.

Dahlia: We’re not telling you all this to scare you to death, but you should know the risks of animal bites and that simply vaccinating your cat will prevent devastating consequences.

Siouxsie: So, Lashonne, please do take your cat to the vet and have him or her check it out. If it is a wound or an abscess, you’ll find out how to treat it properly. If your vet recommends an FeLV and FIV test, have that done.  And in the very unlikely case that the bump is a tumor or other such problem, your vet can help you deal with that, too.

Thomas: If you want to learn about abscesses from a vet’s perspective, check out this entry in the Dolittler vetblog (warning, there are a couple of gross pictures).