Another skin diseases for your personal health care information. Pityriasis versicolor is a common superficial skin infection caused by yeasts of the genus Malassezia. The yeasts are usually found on sebum lipid -rich areas of the body such as the trunk, back, face and scalp. Malassezia yeasts are part of the normal skin flora which may cause infection under certain conditions.
How does Pityriasis versicolor present?
The lesions are most commonly found on the upper trunk, upper arms and neck, which are lipid-rich areas of the body. They present as patches which may be pale (white, pink) or dark (tan, brown, black) with some flaking on the surface. They may be round or oval, and confluent in more extensive lesions. Itchiness may be present in some cases. It may be more of a cosmetic concern in some patients.
Who gets pityriasis versicolor?
Although pityriasis versicolor can occur at any age, it is more common in the adolescents and young adults. Those with malnutrition or on systemic corticosteroids and immunosuppressants, as well as hyperhidrosis (excessive sweating) are also predisposed to developing the infection.
How is it diagnosed?
The diagnosis is usually made clinically from the characteristic appearance and confirmed by microscopy. This involves collecting samples by scraping or stripping off the scales with a cellophane tape. The characteristic ‘spaghetti and meatball’ appearance is indicative of the presence of hyphae and spores. A Wood’s lamp (filtered ultraviolet light with a peak of 365nm) may show a yellowish fluorescence of the affected areas in some cases.
Sunscreens and sun blocks are lotions containing one or more protective chemicals that absorb, reflect or scatter ultraviolet rays. 
