Hot Spots or Acute Moist Pyoderma


Hot Spot in Older Lab with itching problems

Question: On Saturday we noticed that she had a grazed, red raw area about the 1.5 inches across between her shoulder blades. We thought it might be a wound, it was clean, so we left it alone. On Monday night, she rolled on the carpet and the area reopened and bled. It is like a graze, with the white skin looking reasonably healthy round it and some part of the graze being still covered in hair. But in that area the hair has completely gone. I've pplied some vitamin E oil to it, but otherwise left it alone. If you touch her near the area, she immediately wants to scratch her stomach, but she doesn't try to scratch her back. Is this wound likely to be associated with the itching? Or is it probably just a wound!

Thank you for your help.

Regards, Elizabeth

Answer: I think that the wound you are describing is most likely an area of acute moist pyoderma, which is often referred to as a "hot spot". These can occur very rapidly and progress to weepy, scabby wounds so quickly, in some cases, that they are frightening. Keeping these wounds dry with the use of a mild astringent solution or an antibiotic/cortisone powder can be very helpful. I like NeoPredef Powder (tm) which is available in the U.S. but anything that is astringent, controls itchiness or provides antiseptic or anti-bacterial action may help.

Mike Richards, DVM 8/31/2000

Hot spots

Q: What are hot spots, anyway?

A: M-

Hotspots are usually superficial bacterial infections of the skin. They can be caused by anything that irritates the skin enough to allow bacteria to get a foothold and grow. This produces itchiness that makes the dog chew or scratch, which further damages the skin, leading to a bigger area of infection....... and the cycle can go on rapidly and spread widely. I don't know if the name comes from the inflammation that is visible, the warmth around the wound due to the inflammation or the rapidity with which these skin infections can appear and spread. What is usually seen is an area of hairloss with very red skin that may be exuding serum. In some cases there isn't much hairloss but the skin gets crusty or scabbed, anyway. Keeping the areas dry helps to limit their spread but it is often necessary to use some form of itch control to get these to resolve.

Mike Richards, DVM 9/24/99

Hot Spots

Q: My dog has a hot spot on her flank which seems to be spreading. I bought a product at the pet shop called PETRELIEF MEDICATED ANTI-ITCH SPRAY. There is an ingredient in it that discourages the dog from licking or chewing on the infected area, but my dog seems to be able to rub it off and then she continues to irritate the area. Should I give some time, as I just started using this stuff today, or should I take her to the vet before it gets any worse? Thank you, Myra

A: Myra- The important thing when dealing with hotspots is to keep them dry so that they can heal. If the product works for this the hotspot should be comfortable within 24 hours and not spreading. If it doesn't you should take your dog to your vet because uncontrolled hotspots can become a real problem really fast.

Mike Richards, DVM

"Hot Spots" a.k.a. "Acute moist pyoderma"

Q: Hello, I have an 8 year-old Chow Chow named Teddye. I recently noticed a moist spot on the top of his head between the ears reddish in color. I immediately though that he had been struck with something. I was wrong. What the spot turned out to be was a "hot spot". Please give me some information on how these develop and treatment procedures of this condition. Thanks so much.

A: "Hot spots" are also known as "acute moist pyoderma". What that means is that they are rapidly appearing, oozing, skin infections. This is just a description of a symptom, sort of like saying "your dog has scabs".

A hot spot starts because something irritates the dog's skin. The body's response is to either itch or create an inflammatory response at the site. In cases of itching, the dog then rubs, licks or chews the site and adds to the problem. These sores can develop into severe problems in an hour or two at times.

The most common irritants are probably fleas and allergies. These cause the itching that leads to the skin infection. There are many other possible sources of irritation. Tick bites, bee-stings, burrs, mats, mosquitoes, summer heat and other problems all contribute to the initial irritation that can develop into a hot spot.

The best treatment for these is prevention. Keep fleas off your dog. Groom and bathe your dog as necessary to keep the haircoat in good condition. Limit other sources of irritation to the best of your ability. If allergies are a problem for your dog, work with your vet to control the itching they cause. In some dogs, all of this won't be enough and you will occasionally see hot spots anyway. The first step in treating a hot spot is to get it dry. Bacteria like the hot moist environment of irritated skin. Using something to dry the sore makes it harder for bacteria to grow. Clipping the hair over and around a hot spot can help a great deal in allowing it to dry. There are lots of astringents that will help dry the sore, as well. My favorite is NeoPredef powder because it dries the sore, has an antibiotic that acts locally and a corticosteroid to control the itching and inflammation. Other vets and pet owners have their own favorites. People have advocated using athlete's foot powders, over-the-counter medicated powders, Listerine, rubbing alcohol and many other drying agents. Personally, I think rubbing alcohol is too irritating. Antiseptic solutions can also be helpful, especially if they are also a little astringent. Betadine solution is a good antiseptic. If the hot spot doesn't respond very quickly to efforts to keep it dry, then you should seek help from your vet. Small areas of acute moist pyoderma can become large area quickly. Some dogs will continue to dig and scratch until they really damage their own skin. Your vet can help make your dog comfortable pretty quickly in most cases.

Mike Richards, DVM

See photo of "Hot Spot" or Acute Moist Pyoderma


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...