From hot spots to fleas, itchy skin (pruritus) and skin infections (pyoderma) are some of the most common reasons pet parents bring their dogs to the vet. While some cases will fully resolve with appropriate antibiotic treatment, others are more difficult to manage due to complicating underlying factors, such as allergies. These dogs often have chronic and recurrent infections. Luckily, great strides have been made in treating these conditions. Pet parents should be familiar with the signs and symptoms of pyoderma, and here’s what you should know about this common condition.
What is Pyoderma in Dogs?
Pyoderma is a broad term for infection of the skin. The skin condition is often caused by bacteria and can be due to underlying issues such as allergies and/or external parasites.
Symptoms of Pyoderma in Dogs
Pyoderma can vary in appearance but may cause the following changes to the skin and fur coat:
Papules and pustules - small raised red bumps which may contain a pus-filled center (similar to pimples)
Epidermal collarettes, scales, and flakey skin
Scabs or scratches on the skin
Areas of redness and inflammation, which may be moist
Pruritus (itchy skin) - may present as scratching, chewing, licking, or rubbing
Odor associated with the skin
Erect hair follicles which may appear similar to hives
Deeper skin infections may also be painful, oozing blood and pus, and be associated with fever, depression, and decreased appetite
Skin infections can occur anywhere on the body but tend to be most common in areas of skin folds (facial folds in certain breeds, arm-pit area, groin) and between the toes. The underlying cause can also affect where on the body the infection occurs.
Types of Pyoderma in Dogs
Pyoderma can be classified in many ways, depending on the type, cause, and location of the skin infection. Some common terminology that you may hear from your veterinarian includes:
Canine Superficial pyoderma - Skin infections involving the upper layers of the skin and hair follicles.
Folliculitis - Canine superficial bacterial folliculitis is one of the most common types of skin infection involving inflammation of the hair follicles
Moist or pyotraumatic dermatitis - Also known as “hot spots”
Intertrigo - Also known as skin fold dermatitis
Pododermatitis - Skin infection or inflammation of the paws
Deep pyoderma - Infections involving the deeper layers of the skin leading to pain, crusting, and oozing of blood and pus.
Acral lick granuloma - Localized deep infections that occur as a result of chronic and repetitive licking
Furunculosis - A deep skin infection that may be seen between a dog’s toes or, in rare cases, after bathing or grooming
Bacterial overgrowth syndrome - Overgrowth of bacteria on the skin, leading to itching, redness, baldness, and a bad smell
Causes of Pyoderma in Dogs
A dog's bacterial skin infection can occur for various reasons. If the skin is damaged or exposed to excessive moisture, bacteria or yeast can easily colonize the area. The most common type of bacteria associated with these infections is Staphylococcus.
Most cases of pyoderma, however, are associated with an underlying issue.
While allergies in people usually cause red eyes and sneezing, dogs with allergies typically present with itchy skin and recurrent skin and ear infections. There are several things dogs can be allergic to.
While fleas will cause itching in any dog, some dogs actually have an allergic reaction to the bite/saliva of a flea. These animals have an extreme response to even a single flea bite, including itchy skin, hair loss, trauma to the skin, and skin infection. Treatment involves managing any current infections and pruritus, making sure that all pets in the household are on year-round flea prevention, and treating the home environment for fleas.
Dogs generally develop allergies to the protein source in their diet. Even if your dog has been eating the same diet for years, they can still develop a food allergy. In addition to itchy skin, they may have gastrointestinal signs, such as vomiting and diarrhea. A diet trial is needed to diagnose and treat a food allergy. This involves feeding your dog a novel protein or hypoallergenic diet for three months and watching for signs of improvement. During this time, your dog may not eat any other treats or flavored medications.
Pollen, dust, and even cats or people can trigger allergies in a sensitive dog. Environmental allergies, known as atopy, may have a seasonal pattern. If you wish to know what your dog is allergic to or treat them with allergy injections, a blood and/or skin test can be performed. Other ways to control symptoms of environmental allergies include wiping paws when coming in from outdoors and medications to manage symptoms. There are many excellent medications available that help control signs of allergies and decrease the frequency of flare-ups, and this is something your veterinarian can help you with.
Other causes of skin infection include external parasites (fleas, mites, etc.). Systemic diseases (immune-mediated disease, liver disease, cancer, endocrine disorders such as hypothyroidism and Cushing’s Disease) may also cause changes in your dog’s skin. In addition, pain or anxiety can lead to excessive chewing or scratching, which can damage the skin and cause infection.
How is Pyoderma Diagnosed?
Your vet can diagnose pyoderma based on history and physical exam. They may also perform some of the following tests to determine what type of agent is causing the infection and if there is an underlying cause that must be addressed.
Flea comb - It is always important to check for fleas in any dog with itchy skin or a skin infection. Even if fleas are not found, year-round flea prevention will likely be recommended. Some dogs that are allergic to fleas can have an extreme skin reaction to just a single bite.
Cytology - This involves taking a sample of cells from the skin for examination under the microscope. Your vet may collect a sample by pressing a glass microscope slide onto your dog’s skin or using a piece of tape to transfer cells to the slide. Your vet will then look for the presence of yeast or bacteria, and this will help guide their treatment recommendations.
Bacterial culture - In a deep or complex bacterial infection, your vet may suggest a culture to grow the type of bacteria present and determine which type of antibiotic it will respond to.
Fungal culture - This can be used to test for ringworm, a type of fungal infection that can cause skin lesions and secondary pyoderma.
Skin Scrape - If mites are suspected, your vet may use this method to collect a skin sample and evaluate it under the microscope.
Bloodwork - If your vet is concerned about a systemic disease that may predispose your dog to skin infections, such as hypothyroidism or Cushing’s Disease, bloodwork may be indicated.
Allergy testing - Allergy testing may involve referral to a dermatologist for a skin test, a blood test, or a feeding trial with a hypoallergenic diet.
How is Pyoderma Treated?
Treat the Active Infection
Depending on the type and severity of your dog’s skin infection, your vet will recommend a treatment plan, which may include some or all of the following:
Topical treatments such as medicated shampoos or sprays containing antibiotics and antifungal properties. This is the best course of treatment for superficial pyoderma or mild infections. Seek ones that contain ingredients such as benzoyl peroxide or chlorhexidine.
Oral antibiotic therapy such as cephalexin or Clavamox
Oral antifungal medications
Medication to help decrease pruritus and inflammation in the skin, such as steroids, Apoquel, or Cytopoint
A cone to keep your dog from chewing and licking at the area
If this is your dog’s first skin infection, this may be all that is needed. If your dog has had multiple skin infections in the past, your vet will likely discuss additional steps for how to manage and treat the underlying cause.
Treat the Underlying Cause
Dogs with recurrent skin infections will need further testing and treatment. This may involve:
Year-round flea prevention
Hypoallergenic or novel protein diet for dogs with food allergies
Medications such as Apoquel or Cytopoint to manage symptoms of environmental allergies
Medical treatment for any underlying systemic disease
Can Dogs Fully Recover From Pyoderma?
In many cases, pyoderma is easily treatable with appropriate topical therapy or oral antibiotics. If your dog is prescribed antibiotics, it is extremely important to avoid antibiotic resistance by finishing the full course of treatment, even if their skin infection appears to have resolved. Antibiotics are usually prescribed for two weeks, longer for deep skin infections. You should notice an improvement in your dog’s skin and comfort level within a couple of days of starting treatment.
Some dogs will recover from their skin infection and never get another. However, in many cases, skin infections will recur until the underlying condition is diagnosed and managed. This can be extremely frustrating for pet parents. Luckily, many medications are available to help keep these dogs comfortable and keep infections at bay.
How Can Pyoderma be Managed or Prevented?
Keeping your dog up to date on parasite prevention, providing proper grooming, and avoiding overcrowded or unsanitary conditions can help keep your dog’s skin and fur coat clean and healthy. If your dog has an underlying condition, such as an allergy, then you will need to work with your vet to help manage this with diet or medications.
Is pyoderma in dogs contagious to other dogs or humans?
While similar to impetigo (a contagious skin infection seen in people), pyoderma in dogs is luckily not contagious to other animals or people. However, some underlying causes of pyoderma, such as external parasites or ringworm, are contagious. Additional precautions must be taken if your dog’s infection is caused by an antibiotic-resistant bacteria (such as MRSA).
Can pyoderma in dogs be prevented?
In some cases, pyoderma can be prevented by keeping your dog up to date on parasite prevention, providing proper grooming, and avoiding overcrowded or unsanitary conditions. Managing any underlying conditions, such as allergies, through medication and/or diet will also be critical to decrease the severity and frequency of skin infections.
Are there any risk factors for pyoderma in dogs?
Breeds with saggy skin and multiple skin folds may be predisposed to getting skin infections in these areas. Dogs with underlying allergies, external parasites, or certain systemic diseases will also likely suffer from chronic and recurrent skin infections. Animals in shelters or crowded conditions may be more likely to contract external parasites or fungal infections such as ringworm.
Can pyoderma in dogs recur?
In some dogs, pyoderma will fully resolve with treatment and never recur. However, dogs with underlying conditions (such as allergies) will likely get multiple recurrent skin infections throughout their lifetime. The severity and frequency of these infections can be greatly decreased by managing the underlying condition with diet or medications.