Tinea versicolor is a superficial fungal infection caused by the yeast, Malassezia furfur. It consists of small, round to oval papules with fine scale that are usually pinkish in color from inflammation or slightly lighter in color due to reduced pigment (“hypo-pigmented”). The yeast, M. furfur produces azelaic acid, which is a competitive inhibitor of tyrosinase, an enzyme critical for melanin (pigment) synthesis. This explains why it is often lighter in color than normal skin color. However, sometimes paradoxically, the rash may be brownish in color. The rash is usually found on the upper chest and back. It may also appear on the shoulders, upper arms, neck and face. The individual papules may coalesce (join together) to form larger patches. Tinea versicolor is mostly asymptomatic but at times may be slightly itchy. Usually the major concern is its appearance.
Superficial skin scrapings with microscopic examina-tion with KOH will reveal yeast and short mycelial forms.
This test can be done in a typical office visit with a dermatologist but is often not necessary since the clinical appearance is often highly diagnostic. Tinea versicolor is caused by a fungus that is normally present on the skin surface and is therefore not considered to be contagious. Treatment involves the use of topically applied anti fungal creams such as econazole, selenium sulfide. Some times short courses of oral antifungals are needed in more resistant cases.
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