Pyoderma in dogs is a bacterial infection of the skin. Superficial pyoderma refers to bacterial infections that involve the epidermis and portions of the hair follicle near the surface of the skin. Superficial pyoderma includes impetigo, mucocutaneous pyoderma, and bacterial folliculits. Superficial pyoderma is usually secondary to an underlying cause or predisposing factor, which must be identified for effective management of the skin condition.
Common name: Bacterial skin infection, Canine superficial pyoderma, Puppy pyoderma
Scientific name: Superficial pyoderma, Impetigo, Superficial pustular dermatitis, Mucocutaneous pyoderma, Bacterial folliculitis
Impetigo affects young dogs prior to puberty and may be associated with endoparasitism (intestinal worms), poor nutrition, or a dirty environment. German Shepherd dogs and their crosses are more commonly affected by mucocutaneous pyoderma.
While the exact incidence of superficial pyoderma is unknown, it is considered very common. The most common type of superficial pyoderma in dogs is bacterial folliculitis, an infection of the hair follicle.
There is no known geographic predilection for this disease.
Clinical signs (primary, most to least frequent, scientific term, synonyms)
Papules (red bumps), Pustules (pimples), crusts (scabs), Epidermal collarettes (well circumscribed areas of redness and hair loss with a dark center), Patchy alopecia (hair loss), moth-eaten‚ excessive shedding, erosion, fissuring, and depigmentation of the mucocutaneous junctions (lips, eyelids, nose, vulva, prepuce, anus).
Clinical signs (secondary, most to least frequent, scientific term, synonyms)
Pruritus (itch), Seborrhea sicca (dull coat with scale), Seborrhea oleosa (greasy hair coat).
Cause (scientific, common term)
Infection due to Staphylococcal bacteria; most commonly Staphylococcus intermedius; rarely other bacteria.
Organ system affected(most to least affected)
Skin cytology (impression smear, acetate tape preparations) to evaluate for infection, skin scraping, fungal culture, skin biopsy, bacterial culture and sensitivity. Other diagnostic tests may be indicated to evaluate for an underlying disease condition, such as allergy, ectoparasites, systemic disease.
Demodicosis (Demodex), Dermatophytosis (ringworm; fungal infection), Malassezia dermatitis (yeast infection of skin), Auto-immune skin disorders.
Pyoderma is a bacterial infection of the skin. Superficial pyoderma refers to bacterial infections that involve the epidermis and portions of the hair follicle near the surface of the skin. Superficial pyoderma includes impetigo, mucocutaneous pyoderma, and bacterial folliculits. Superficial pyoderma is usually secondary to an underlying cause or predisposing factor. The most common bacterial organism involved in superficial pyoderma is Staphylococcus intermedius, which is a normal inhabitant of the skin of healthy dogs. Organisms may be introduced by local trauma, scratching, or an infection resulting from contamination due to a poorly kempt coat, parasitic infections, hormonal factors, local irritants, or allergies.
Impetigo is a condition most commonly recognized in puppies prior to puberty and involving the non-haired skin, such as the groin and armpit areas. Predisposing factors include parasites (internal and external), poor nutrition, or environmental factors. Mucocutaneous pyoderma is limited to the mucocutaneous junctions (usually the lips, but also the eyelids, nose, vulva, prepuce, and anus) and German Shepherd dogs and their crosses are over represented. Superficial bacterial folliculitis is the most common cause of superficial pyoderma and affects dogs of all ages and breeds.
In all three types of superficial pyoderma, the clinical signs may include papules (red bumps), pustules (pimples), crusts (scabs), and epidermal collarettes (well circumscribed areas of redness and hair loss with a dark center). Most dogs are very itchy. Mucocutaneous pyoderma may manifest as lip swelling, erosions, fissures, crusts, and loss of pigment (color) while excessive shedding and hair loss in a moth-eaten‚ patchy pattern may be evident with bacterial folliculitis.
The diagnosis of superficial pyoderma is based on history and clinical signs. Skin cytology (sampling) followed by microscopic examination may confirm the diagnosis. Because pyoderma is often a secondary disease with an underlying cause, further diagnostics, including a skin scraping, fungal culture, and biopsy may be indicated. Bacterial cultures are often performed to identify the type of bacteria involved and to guide appropriate therapy. Finally, when pyoderma is recurrent, it is very important to evaluate for other underlying diseases, such as systemic, endocrine (hormonal), and allergic conditions, that result in susceptibility to infection.
There is no primary home care treatment for superficial pyoderma.
A veterinarian may prescribe a safe and effective treatment program that includes both topical (applied to the skin) and oral (by mouth) antibiotic therapy. Oral antibiotic therapy is administered for a minimum of three weeks. Therapeutic bathing is also very beneficial in management.
Diagnosis and development of a treatment plan should be made by a veterinarian.
Prognosis is good if the underlying cause can be identified and corrected or controlled.
Scott, DW, Miller WH, Griffin CE. Parasitic Skin Diseases. In: Kersey, R, DiBeradino, C, eds. Muller and Kirk's Small Animal Dermatology. Philadelphia: W.B. Saunders, 2001; 288-296.
Medleau, L, Hnilica KA. Small Animal Dermatology: A Color Atlas and Therapeutic Guide. Philadelphia: W.B. Saunders, 2001; 11-12; 15-17.
Jeanne B. Budgin, DVM, DACVD
Steven Hansen, DVM, MS, MBA, DABVT, DABT