Tinea versicolor
Tinea versicolor (pityriasis versicolor) is a common superficial fungal infection caused by Malassezia yeast, producing hypopigmented, hyperpigmented, or erythematous scaly macules that coalesce into patches on the upper trunk and fail to tan with sun exposure. Diagnosis is confirmed by a potassium hydroxide preparation showing a spaghetti-and-meatballs pattern, and first-line treatment is topical ketoconazole 2% shampoo or selenium sulfide 2.5% lotion, with oral itraconazole reserved for extensive or recurrent disease.
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What this article covers
- Overview
Definition: tinea versicolor, also called pityriasis versicolor, is a common, recurrent, superficial fungal infection of the stratum corneum caused by Malassezia yeast species that are normally part of resident skin flora.
- Epidemiology
Age group: most common in adolescents and young adults.
- Risk factors
Humid, sweaty conditions and oily skin: create a warm, lipid-rich environment that favors Malassezia overgrowth.
- Pathophysiology
Commensal-to-pathogen transition: Malassezia yeast, a normal component of skin flora, proliferates excessively in the stratum corneum when local conditions (heat, humidity, sebum) favor it.
- Clinical features
Diagnostic morphology: small, scaly, variably colored (hypopigmented, hyperpigmented, or pink) macules and patches, most often on the chest or back, that can coalesce into larger patches, defines the clinical picture.
- Differential diagnosis
Vitiligo: completely depigmented, sharply demarcated macules with no scale and complete absence of fluorescence pattern differences on Wood's lamp, unlike the fine scale and incomplete pigment loss of tinea versicolor.
- Diagnosis
The diagnosis is confirmed by a potassium hydroxide preparation of skin scale showing the characteristic "spaghetti and meatballs" pattern of short hyphae and round yeast forms, which is the best initial test.
- Management
First-line, topical selenium sulfide 2.5% lotion: apply to affected body surfaces, lather with a small amount of water, leave in place for 10 minutes, rinse thoroughly, and repeat once daily for 7 days.
- Complications
Persistent pigment alteration: hypopigmented or hyperpigmented patches can remain visible for weeks to months after the infection itself has been eradicated, causing cosmetic concern even after cure.
- Prognosis
Excellent with treatment: the fungal infection responds well to topical or, when needed, oral antifungal therapy.
- Prevention
Address modifiable risk factors: manage excess sweating and oiliness, and control predisposing conditions such as diabetes or corticosteroid exposure where possible.
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Related articles
- Seborrheic dermatitis
Seborrheic dermatitis is a common chronic inflammatory reaction to Malassezia yeast that produces ill-defined erythema with dry or greasy scale in sebum-rich sites such as the scalp, nasolabial folds, brows, and ears. Diagnosis is clinical based on distribution; first-line treatment is topical ketoconazole cream or shampoo with a short course of low-potency hydrocortisone for inflamed flares, and disseminated or severe disease should prompt screening for HIV or a neurologic disorder.
- Pityriasis rosea
Pityriasis rosea is an acute, self-limited papulosquamous eruption, often linked to human herpesvirus 6 or 7 reactivation, that begins with a solitary herald patch and is followed by smaller collarette-scaled plaques along skin cleavage lines in a Christmas tree pattern. No treatment is required because the eruption self-resolves, usually within about 6 weeks; oral cetirizine 10 mg once daily can control itching, and topical glucocorticoids relieve symptoms while the rash clears on its own.
- Vitiligo
Vitiligo is a common acquired autoimmune condition in which destruction of melanocytes produces well-demarcated, completely depigmented macules and patches without scale, most often on the extensor surfaces, hands, face, and periorificial skin. Diagnosis is clinical, supported by Wood's lamp examination showing bright, sharply delineated fluorescence, and first-line treatment is a topical high-potency corticosteroid or a topical calcineurin inhibitor such as tacrolimus, with phototherapy for widespread disease.