Dog skin infections, or what are often called “Hot Spots,” are usually caused by a bacterium called Staphylococcus Intermedius, although other bacteria can also cause skin infections. In most cases, the cause remains unknown, although they are often due to some underlying factor such as fleas, mites, bacteria, allergies, or irritants such as harsh shampoos. In some cases, a severe essential fatty acid deficiency may also be the cause.
It is suspected that increases in the temperature and humidity of the skin environment may play a role in the development of these skin infections. This is probably why hot spots tend to be more common in the summer than in the winter. Often, hot spots may occur after a dog has been swimming in a lake or river, likely because this suddenly changes the temperature and humidity of the skin microenvironment. Dogs that are prone to allergies also tend to get hot spots more readily than non-allergic dogs.
At one time, all hot spots were thought to be the same and, as a result, were all treated the same way. However, research has shown that there are actually two distinct forms of hot spots (also known as acute moist dermatitis), namely superficial hot spots and deep hot spots. Correctly identifying which type of hot spot maybe affecting your dog helps the veterinarian determine the correct treatment and possibly even the cause.
Superficial hot spots are, as the name implies, on the skin surface and appear as a moist patches of inflamed, ulcerated, itchy skin with matted hair. They are easily treated by clipping back the hair from the affected area, and then cleansing infected area with a medicated soap and water, followed by application of an appropriate topical medication.
The second type of hot spot is the deep hot spot. It is quite different from the superficial form in that there is itchiness, ulceration and inflammation but also a very deep infection and oozing. Unlike the superficial kind of hot spot, these hot spots must be treated with antibiotics as well as topical treatment. They are seen most often in young dogs and in certain breeds such as Golden Retrievers and Saint Bernards.
Preventing skin infections is difficult unless an underlying cause can be determined. If you can't determine the cause, there are some things you can do to lessen the probability of your dog getting hot spots. For example, giving medicated bathes (e.g. benzoyl peroxide shampoos) on a regular basis may help prevent some cases from reoccurring. Supplementing your dog's diet with an essential fatty acid supplement may also prove helpful. Early detection of hot spots before they become serious is also an important part of any preventative program. Your veterinarian should be consulted if your dog gets a hot spot so that you can both work together to relieve your pet’s suffering, as well as determine the cause and course of treatment.