Slightly itchy, superficial fungus infection of the skin, with characteristic brown patches, caused by Malassezia furfur, which can be detected in the patches by microscopic examination. The patches form on chest, back and shoulders; they are usually pale pink to brown. In dark-skinned people the patches are lighter than the surrounding skin, darker if the skin is fair, hence the name ‘versicolor’. Like all fungus infections, pityriasis versicolor can be treated with a fungicidal cream; symptoms disappear within a few days to a week. An alternative treatment is washing the whole body with a sulphur shampoo once a week for three consecutive weeks.