Any type of cat can develop hot spots, and we’re not talking about a wireless connection to the Internet or a trendy place. A hot spot in a cat is a very itchy skin infection, also called acute moist dermatitis and pyotraumatic dermatitis. In cats they are sometimes even referred to as miliary dermatitis.
Hot spots can happen to any cat, but cats with fleas or a history of allergies are more prone to developing a hot spot. Cats with long, thick coats may also be more prone to developing a hot spot.
Signs Of A Cat With A Hot Spot
When a cat comes into my hospital showing hair loss or hair being matted to the skin, along with the skin being very red from inflammation and fluid oozing from the skin infection, I suspect a hot spot. The matted fur may prevent you from seeing just how big the hot spot is. These spots are usually hot to the touch from the localized inflammation and skin infection. Cats with hot spots usually lick, chew or scratch the area excessively because it is very itchy. Your cat can rapidly make the hot spot much worse with the nonstop licking, chewing and scratching. Hot spots can also be quite painful to your cat.
What Causes A Hot Spot?
Parasites, allergies, infections, warm weather and anything that makes your cat itchy can cause a hot spot. In general, I see hot spots more in the spring, summer and fall. This is also bug and allergy season, when the weather is warm and humid.
- Parasites: In my experience, fleas are the most common cause of hot spots in cats, but other parasites—such as mites (ear mites, sarcoptic and demodectic), mosquitoes, flies and even ant bites—can cause the initial irritation that starts a hot spot.
- Allergies: After parasites, allergies are the second most common cause of hot spots. Cats can have seasonal allergies to pollen, grass, trees, weeds, fungus and dust mites. Cat food allergies and allergies to fleabites can also cause hot spots. Cats have a different reaction to allergens than people. People typically develop a runny nose, runny eyes and a lot of sneezing. Cats usually develop itchiness to the skin. Some cats are actually allergic to flea saliva, so just a few fleabites can cause them to be extremely itchy.
- Infections And Pain: Another possible source of hot spots is ear infections. The ear infection is itchy, so your cat scratches at the ears and some of the skin below the ear. The self-trauma from scratching can lead to a hot spot just below the ear. Ringworm infections are sometimes itchy enough to cause a hot spot to develop. A few hot spots are related to painful conditions like hip arthritis. This could cause your cat to lick and chew at the skin above the hips, causing a hot spot to form on that area.
Diagnosis Of A Hot Spot
Most hot spots can be diagnosed with just a physical exam. The typical inflamed and infected skin lesions are easy for a veterinarian to recognize. Identifying the underlying cause of the hot spot is the more challenging part for your veterinarian. It is important to determine the cause of the hot spot, so appropriate action can be taken to prevent more hot spots in the future.
How To Treat A Hot Spot
When I treat a hot spot, it usually requires several steps.
- First, I shave off the matted fur. Sometimes this requires sedating the cat to make shaving the area of the lesion possible. Shaving allows me to see how big the lesion is and how deep the skin infection is. It also helps the skin to heal faster.
- Next, I clean the skin with a surgical scrub like chlorhexidine, which is mild on the skin.
- Now it is time to stop the itch. This is usually done by giving an injection of cortisone. Fortunately, cats are not prone to most of the side effects from cortisone that people and dogs get.
- The fourth step is to treat the skin infection. This can be easily accomplished with an injection of Convenia, which is a long-acting antibiotic. Ringworm infections require either a topical anti-fungal medication or an oral anti-fungal tablet.
- Finally, an Elizabethan collar is placed on the cat to prevent her from licking and chewing at the skin lesion. This process clears up most hot spots, but you also have to treat the underlining problem that caused the itchy skin, and hence, the hot spot, to develop in the first place.
In my experience fleas are the most common cause of hot spots. Thus, strict flea control for your cat is a must. Consult your veterinarian about the best flea control to use for your cat. In more severe flea infestations, spraying the yard and treating the house may also be necessary.
Preventing Hot Spots
In general, hot spots are not contagious, but fleas, ringworm infections and some mites can be spread from one cat to another cat. Thus, if you have multiple pets and one gets fleas, you must treat all the pets in your home with a flea product. Some of the newer prescription flea products can also control ear mites and skin mites.
Although you can’t prevent allergies, these can usually be controlled with cortisone injections, tablets or liquid suspension. In addition, your veterinarian can refer you to a veterinary dermatologist for allergy skin testing and immunotherapy (allergy shots) to control the allergies.
Keeping fleas, mites and allergies under control will usually prevent a reoccurrence of a hot spot. Frequent grooming and brushing will also help; however, if you notice any problem with your cat’s skin, or if your cat is frequently licking and chewing at the skin, then it is time to take your cat to your veterinarian for treatment before the skin problem becomes worse.
By: Jerry Murray, DVM
Featured Image: Gina Cioli/I-5 Studio