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Tinea versicolor (pityriasis versicolor) is skin infection with Malassezia furfur that manifests as multiple asymptomatic scaly patches varying in color from white to brown. Diagnosis is based on clinical appearance and skin scrapings. Treatment is topical antifungal drugs.

Malassezia furfur is a dimorphic fungus that is normally a harmless component of normal skin flora but that in some people causes tinea versicolor. The high prevalence of tinea versicolor in young adults suggests a link to increased sebaceous secretions; other risk factors include heat and humidity and immunosuppression due to corticosteroids, pregnancy, malnutrition, diabetes, and other disorders.

Symptoms and Signs

Tinea versicolor usually is asymptomatic. Classically, it causes the appearance of multiple tan, brown, salmon, or white scaling lesions on the trunk, neck, abdomen, and occasionally face. The lesions coalesce. In whites, the condition is often diagnosed in summer months because the lesions, which do not tan, become more obvious against tanned skin.

Tinea Versicolor

Diagnosis

• Clinical appearance
• Potassium hydroxide wet mount
• Sometimes Wood's light examination

Diagnosis is based on clinical appearance and by identification of hyphae and budding cells (“spaghetti and meatballs”) on potassium hydroxide wet mount. Wood's light examination reveals golden-white fluorescence.

Treatment

• Topical antifungals
• Sometimes oral antifungals

Treatment is any topical antifungal drug. Examples include selenium Some Trade Names
SELSUN
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sulfide shampoo 2.5% (in 10-min applications daily for 1 wk or 24-h applications weekly for 1 mo); topical azoles (eg, ketoconazole Some Trade Names
NIZORAL
Click for Drug Monograph
2% daily for 2 wk); and bathing with zinc pyrithione soap 2% or sulfur-salicylic shampoo 2% for 1 to 2 wk.

Oral treatment is indicated for patients with extensive disease and those with frequent recurrences. Two convenient regimens are a single 400-mg dose of fluconazole Some Trade Names
DIFLUCAN
Click for Drug Monograph
and ketoconazole Some Trade Names
NIZORAL
Click for Drug Monograph
200 mg once/day for 1 to 5 days.

Hypopigmentation from tinea versicolor is reversible in months to years after the yeast has cleared. Recurrence is almost universal after treatment because the causative organism is a normal skin inhabitant. Fastidious hygiene, regular use of zinc pyrithione soap, or once-monthly use of topical antifungal therapy lowers the likelihood of recurrence.

Last full review/revision August 2008 by A. Damian Dhar, MD, JD

Content last modified August 2008