FIGURE 16-1 Nasal Pyoderma.

A, Alopecic, crusting, papular dermatitis on the nose before treatment is provided. B, Following 3 weeks of aggressive antibiotic therapy (high dose, long duration, and optimal frequency), the bacterial folliculitis and furunculosis were resolving.

FIGURE 16-2 Pyoderma.

A, An adult German shepherd with generalized bacterial folliculitis and furunculosis. The fur has been clipped, revealing numerous crusting, papular lesions with drainage. B, After aggressive antibiotic therapy (high dose, long duration, and optimal frequency), the bacterial folliculitis and furunculosis have resolved.

FIGURE 16-3 Pyoderma.

A, Severe erythematous dermatitis with numerous epidermal collarettes. B, After aggressive antibiotic therapy, the pyoderma has improved, but numerous epidermal collarettes remain apparent. This dog had a multidrug-resistant Staphylococcus schleiferi infection.

FIGURE 16-4 Pyoderma.

A, Alopecia and lichenification on the ventral neck caused by bacterial pyoderma. Note the similarity to Malassezia (yeast) dermatitis. B, After aggressive antibiotic therapy (high dose, long duration, and optimal frequency), the bacterial folliculitis and furunculosis have resolved.

FIGURE 16-5 Pyoderma.

A, An erythematous papular rash on the abdomen of a dog with bacterial folliculitis is characteristic of pyoderma in dogs. B, After aggressive antibiotic therapy (high dose, long duration, and optimal frequency), the bacterial folliculitis and furunculosis have resolved.

FIGURE 16-6 Pyoderma.

A, This erosive dermatitis was caused by an aggressive Staphylococcus infection in an adult German shepherd. Staphylococcus exotoxins are likely responsible for the erosive lesions (similar to Staphylococcus scalded skin syndrome). B, After aggressive antibiotic therapy (high dose, long duration, and optimal frequency), the bacterial folliculitis and furunculosis have resolved.

FIGURE 16-7 Pyoderma.

Same dog as in Figure 16-6. A, Erosive lesions caused by the aggressive Staphylococcus infection developed on the abdomen. B, After aggressive antibiotic therapy (high dose, long duration, and optimal frequency), the bacterial folliculitis and furunculosis have resolved.

FIGURE 16-8 Nocardiosis.

A, An erythematous plaque on the inner thigh with exudate. This plaquelike lesion is unusual for Nocardia, which typically causes a more deep cellulitis. B, After aggressive therapy with trimethoprim-sulfa, the lesions were resolving.

FIGURE 16-9 Nocardiosis.

Same dog as in Figure 16-8. A, This unusual plaque is not typical of the cellulitis lesions associated with nocardiosis. B, After aggressive therapy with trimethoprim-sulfa, the lesions were resolving.

FIGURE 16-10 Malasseziasis.

A, Generalized alopecia with hyperpigmentation and lichenification in the characteristic “elephant hide” pattern associated with yeast dermatitis. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved. The underlying/primary condition (allergies or endocrine disease) must be controlled to prevent recurrence of the infection.

FIGURE 16-11 Malasseziasis.

A, Severe erythematous, alopecic, lichenified dermatitis on the face of a dog caused by secondary yeast dermatitis associated with primary allergic dermatitis. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-12 Malasseziasis.

A, Severe alopecia, hyperpigmentation, and lichenification of the face and axilla in the classic “elephant hide” pattern typical of yeast dermatitis. B, After several weeks of systemic and topical antifungal and antibacterial therapy, the yeast dermatitis was resolving.

FIGURE 16-13 Malasseziasis.

A, Alopecia and lichenification on the face and neck of a young miniature pinscher caused by a secondary yeast infection associated with food allergy. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved. The food allergy was treated with a dietary food trial.

FIGURE 16-14 Malasseziasis.

A, Alopecia, hyperpigmentation, and lichenification on the face and periocular skin of an adult Cocker spaniel with allergic dermatitis. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-15 Malasseziasis.

Same dog as in Figure 16-14. A, Alopecia and lichenification of the tail base caused by secondary yeast dermatitis. Note the similarity to flea allergy dermatitis. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-16 Malasseziasis.

A, Severe alopecia, hyperpigmentation, and lichenification on the ventral tail and perianal region in a dog with severe secondary yeast dermatitis. Based on the perianal distribution, food allergy dermatitis should be considered as a possible primary condition. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-17 Malasseziasis.

A, Alopecia, hyperpigmentation, and lichenification in the characteristic “elephant skin” pattern associated with secondary yeast infection. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-18 Malasseziasis.

A, Alopecia and lichenification of the axillary region are characteristic of yeast dermatitis. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-19 Malassezia Otitis.

A, Erythema, lichenification, and stenosis of the external ear canal with a moist exudate. Cytologic evaluation demonstrated a predominant secondary yeast infection. B, After several weeks of systemic ketoconazole and topical Otomax therapy, the yeast otitis has resolved. The moist material is Otomax. Note that with resolution of the infection and treatment with topical steroids, the ear canal swelling has decreased considerably.

FIGURE 16-20 Malasseziasis.

A, Alopecia and lichenification on the foot of an allergic dog with secondary yeast pododermatitis. The interdigital space is usually the predominant site of secondary bacterial and yeast infections; however, in this patient, the dermatitis extended to the dorsal surface of the foot. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-21 Malasseziasis.

A, A dark exudate has caused clumping of the hairs and crust formation of the periocular skin and muzzle in this cat with secondary yeast dermatitis. Note the similarity to feline pemphigus and idiopathic facial dermatitis of Persians. B, After several weeks of systemic itraconazole (ketoconazole produces many adverse effects in cats) and topical antifungal therapy, the yeast dermatitis resolved.

FIGURE 16-22 Malasseziasis.

A, Generalized alopecia, erythema, and lichenification in an adult dog with secondary yeast dermatitis associated with an underlying allergy. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved. Note that the dog was still pruritic from the underlying allergic disease, which remains uncontrolled.

FIGURE 16-23 Malasseziasis.

A, Alopecia, hyperpigmentation, and lichenification in the characteristic “elephant hide” pattern associated with yeast dermatitis. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the yeast dermatitis has resolved.

FIGURE 16-24 Dermatophytosis.

A, Focal alopecia and erythema on the muzzle of an adult Dachshund. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the dermatophytosis has resolved.

FIGURE 16-25 Dermatophytosis.

Same dog as in Figure 16-24. A, The alopecia and erythema caused by folliculitis affect only the haired portion of the nose, unlike autoimmune skin disease, which would affect nonhaired nasal planum. B, After several weeks of systemic ketoconazole and topical antifungal therapy, the dermatophytosis has resolved.

FIGURE 16-26 Demodicosis.

A, Generalized alopecia and crusting papular rash on the face caused by demodicosis. B, After several months of systemic miticidal therapy, the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-27 Demodicosis.

A, Generalized alopecia, crusting, and papular dermatitis affecting an adult dog. B, After several months of systemic miticidal therapy, the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-28 Demodicosis.

A, Generalized alopecia, crusting, and papular dermatitis on the head of an English bulldog puppy. B, After several months of systemic miticidal therapy (ivermectin), the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-29 Demodicosis.

A, Generalized alopecia and papular dermatitis covering the entire body. B, After several months of systemic miticidal therapy (ivermectin), the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-30 Demodicosis.

A, Periocular alopecia in a young mixed-breed dog. B, After several months of systemic miticidal therapy (ivermectin), the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-31 Demodicosis.

A, Generalized alopecia and papular rash in a Boxer puppy. B, After several months of systemic miticidal therapy (ivermectin), the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-32 Demodicosis.

A, Generalized alopecia, hyperpigmentation, and crusting papular dermatitis in a dog with iatrogenic Cushing’s (caused by numerous long-acting injectable steroid treatments). B, After several months of systemic miticidal therapy (ivermectin), the Demodex infection is improving. The alopecia and hyperpigmentation will take longer to resolve because of iatrogenic Cushing’s.

FIGURE 16-33 Demodicosis.

A, Generalized crusting papular dermatitis with draining tracts caused by severe folliculitis and furunculosis. B, After several months of systemic miticidal therapy, the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).

FIGURE 16-34 Demodicosis.

A, Generalized alopecia with a crusting papular rash. B, After several months of systemic miticidal therapy, the Demodex infection resolved (based on two consecutive negative skin scrapes 3 weeks apart).