Furunculosis is a painful skin disease that causes pus-filled boils on the body of your dog. The boils often are recurring and may be found near your dog’s anus, in the webbing between your dog’s toes, or on his back, abdomen, back legs and nose. Treatment is effective, though recurrence is common.

Furunculosis is a skin disease that causes boils filled with pus. In cases of idiopathic furunculosis, the cause of the infection is not known. German Shepherds and breeds mixed with German Shepherds are predisposed to the condition.

Furunculosis is a skin disease that produces boils (also called furuncles) that are filled with pus. Often, the boils recur, typically on the nose, around the anus, back, abdomen, legs (particularly the lateral thigh), paws and muzzle. Other symptoms include:

Types 

There are several types of furunculosis, to include:

Idiopathic means “without known cause”. In cases of idiopathic furunculosis, it is not clear what it is that has caused the infection. Furunculosis that is not idiopathic may be caused by certain bacteria, for example Staphylococcal spp., as well as conditions that are not hygienic combined with a weakened immune system. Furunculosis that affects the skin is typically due to bacterial, fungal or parasitic infection. Canine atopy and demodicosis are conditions that are known to cause furunculosis.

Interdigital furunculosis may be caused by:

Anal furunculosis may be caused by there being feces in the anal area that will attach to the tail of your dog. The tail will then spread the feces around the perineal area. This will cause the skin under the tail of your dog (around the anus) to become inflamed and ulceration will occur, possibly leading to infection. German Shepherds and German shepherd mixes are more likely to suffer from this condition than other dogs.

When noticing boils on your dog’s body, a trip to the veterinarian is in order. Your veterinarian will conduct a physical exam and consider your dog’s history. You will want to be prepared to tell your veterinarian when you first noticed the boil or boils on your dog, along with any other symptoms or changes in behavior that you have observed. Depending on the physical examination, your veterinarian may choose to get a closer view of the infection through skin scrapings, smears or fine needle aspirates in order to confirm the diagnosis.

Upon diagnosis, your veterinarian will likely recommend antibiotics and topical antimicrobials. In many cases, antibiotics are given for a long period of time. Other possible recommendations include:

When treatment is not successful, it is often due to the dose or duration of antibiotics not being enough. Other reasons for unsuccessful treatment include your veterinarian being unable to identify and resolve any predisposing factors, as well as your dog taking corticosteroids while receiving treatment for furunculosis.

While your dog is undergoing treatment, you will want to keep the infected areas well ventilated and dry. In addition, it is important that you maintain proper hygiene for your dog and provide him with a diet that meets his nutritional needs in order to boost his immune system. This will help him better fight his infection. With treatment, you will typically notice symptoms receding within 4-12 weeks. It is fairly typical for symptoms to recede and then reoccur during treatment.

If your dog is predisposed to furunculosis, he will likely experience relapses. As furunculosis has a high likelihood of recurring, your veterinarian will probably recommend regular follow up visits. In some cases, the dog will require antibiotics throughout his life.