Small Animal Dermatology, 3rd edition

CHAPTER 32 MALASSEZIADERMATITIS 485

Common Misconceptions Held by Pet Owners

Misconception Fact

Antibiotic therapy in dogs causes yeast

infections

Malasseziaand staphylococci are synergistic on the

skin; There is no evidence that antibiotics cause an

overgrowth of yeast. Yeast numbers are enhanced

when the skin is co-colonized with bacteria

Oatmeal shampoos “feed” yeast

infections

Shampoos have too limited a contact time to

encourage yeast overgrowth; carbohydrates do not

“feed” yeast organisms

Coconut oil is anti-yeast Topical coconut oilencouragesyeast overgrowth

by providing more lipids

Brewer’s yeast induces yeast infections No supporting scientific data; brewer’s yeast is

Saccharomyces cerevisiae(notMalasseziasp.); may

increase salivary IgA in humans

Most important way to manage yeast

infections is with diet

Most important way to manage yeast infections is

identification and control of the underlying cause

(e.g., allergy). The diet is not relevantunlessthe

underlying etiology is a cutaneous adverse food

reaction

Carbohydrates, sugars, and starch in the

diet encourage yeast overgrowth Dietary

supplements that reduce yeast organisms

include garlic, thyme, oregano, parsley,

apple cider vinegar, coconut oil, and

fermented vegetables; probiotics,

goldenseal, and caprylic acid can restore

normal cutaneous yeast populations

No scientific support. Dietary carbohydrates have

no direct link toMalasseziadermatitis. The quantity

of these ingredients in the diet has no effect on

yeast populations; these dietary ingredients do not

directly reach the skin; hypersensitivity to dietary

carbohydrates is uncommon

Antifungal rinses or sprays should be

composed of apple cider vinegar,

“essential oils,” lemon juice, peppermint

or lavender oil mixed with water

ASPCA reports that essential oils can be toxic if

ingested. Vinegar (any type) applied as a 1:10

dilution is acidic and lowers skin pH – can help

reduce yeast populations

Immune testing for IgG, IgA, and IgM will

tell you if your dog is immunodeficient;

these levels are low in a dog with chronic

yeast infection

Tests are not specific; increased, rather than low,

IgA and IgG levels have been detected in serum of

dogs with yeast overgrowth; however, these

immunoglobulins are not considered protective;

immune deficiency may actually decrease

Malasseziadermatitis by preventing a

hypersensitivity reaction; intradermal allergy testing

can detect hypersensitivity toMalassezia