Dear Dr. Thompson: Our 5-year-old golden retriever has had an issue with recurring skin infections that come back every couple of months. We get antibiotics and it seems to clear up, but then we are back at square one. What is causing this and will we reach a point where the antibiotics aren't going to work?
Bacterial skin infections, called pyoderma, are a very frustrating condition for everyone involved, including your dog. The most common symptoms people notice are scratching or excessive licking with crusty scabs and hair loss. Some dogs will develop a greasy coat because of irritation of the oil glands of the skin.
Skin is a very slow-growing organ and once bacteria become established in the deeper layers of the skin, treatment can take weeks to insure the infection has completely resolved. Skin infections are especially insidious since outwardly they may look cleared up, but a small crust or scab here or there indicates the infection is still active. Even the smallest spot can be a source of re-infection that may show up weeks to months down the road.
Typically treatment involves common oral antibiotics twice a day for three weeks minimum. Some infections will also respond well to specific antibacterial shampoos if your dog is a good sport about a bath. It can also be important to avoid long-term steroid medications for itching if at all possible since they can interfere with the normal immune function of the skin and increase the time it takes to clear the infection.
Unfortunately, many skin infections are a symptom of another underlying disease. Allergies create a breakdown in the healthy barrier of the skin, allowing bacteria to take hold. Some serious hormonal diseases that suppress the immune system will lead to recurring infections. Diabetes, chronically low thyroid, and an overactive adrenal gland are the most common conditions, but other symptoms will usually be present, such as increased thirst or weight gain. Without addressing the primary condition the infections will return.
Your concern about developing resistance to the antibiotics is legitimate, but fortunately the bacteria we see with most recurring skin infections do not develop resistance to the most common treatments. One notable exception is a drug-resistant staph infection that is a serious problem in people called MRSA. What was once a rarity in pets now can occasionally be seen. Most often these infections are linked to owners who work in the human health care field who are carriers of the bacteria. If your dog's infection does not resolve, your veterinarian may culture a section of skin to make sure nothing more serious is going on.
The good news is that with a little diligence and regular followup with your veterinarian, you should be able to clear this problem. But be prepared to investigate an underlying problem if you continue to have an issue with these infections.
Questions for Dr. Gary Thompson can be e-mailed to firstname.lastname@example.org or mailed to The Blade, Attn. Ask the Vet, 541 North Superior St., Toledo, OH 43660. Dr. Thompson regrets that he cannot answer individual letters.