Pi-oh trah-ma-tick
derm - ah - titis
Pyotraumatic dermatitis, or "hot spots," are self-induced skin lesions that are usually caused (and made worse) by biting, licking, constant chewing or scratching.
Broken down, this term gives us a glimpse of what the condition looks like: "pyo-" refers to "pus", "-traumatic" refers to self-inflicted trauma (biting, licking, scratching, etc) and "dermatitis" means inflammation of the skin. This inflammation manifests as any or all of the following: redness, oozing, hair loss, and pus.
This condition usually appears suddenly, and is a "vicious cycle" type of problem: an inciting factor for causing the animal to scratch and bite (skin irritation, parasites, etc.), continual licking, scratching and biting, and finally normal skin surface bacteria multiplying, causing the dermatitis (skin infection) that causes more licking, chewing, and scratching.
The area will need to be cleansed, clipped free of hair, and dried out. It is wise to consult first with your veterinarian to help determine the cause of the dermatitis and address that as well as the dermatitis itself. It is important to note that some hot spots are painful to the animal, so caution is advised.
Additional Reading:
How to soothe a hot spot
What Is A "Hot Spot"?
(Detailed version)
