ref:http://en.wikipedia.org/wiki/Tinea_versicolor
Hi,
Tinea versicolor or pityriasis versicolor is a common skin infection caused by the yeast Malassezia furfur . This yeast is normally found on the human skin and only becomes troublesome under certain circumstances, such as a warm and humid environment.
Generally oval or irregularly-shaped spots of 1/4 to 1 inch in diameter, often merging together to form a larger patch, which commonly affect the back, underarm, upper arm, chest, lower legs, and neck.
Topical antifungal medications - containing either 2.5% selenium sulfide or 2% ketoconazole (Nizoral ointment and shampoo) applied to dry skin and washed off after 10 minutes, repeated daily for 2 weeks is the treatment.
Recurrence is common and may be reduced by intermittent application of topical agents (such as tea tree oil) or adding a small amount of anti-dandruff shampoo to water used for bathing.
The diagnosis can be made within the lesions, under the microscope where the fungi typically have a so called "spaghetti and meat ball appearance" .
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