Snapshot A 15-year-old girl presents to her pediatrician’s office for a routine check-up prior to school starting. She has no complaints. She spent a summer in Hong Kong. On physical exam, her physician notices multiple faint light-colored macules and patches along her back, breasts, and abdomen. She collects some skin scraping and prepares a wet mount with potassium hydroxide. Under microscopy, she sees multibranching hyphae and budding that resembles spaghetti and meatballs. Introduction Clinical definition very common cutaneous fungal infection characterized variably colored macules and patches also known as pityriasis versicolor Epidemiology prevalence 30-40% in tropical climates 1-4% in temperate climates demographics most common in adolescents and young adults risk factors hot and humid weather excessive sweating immunosuppression Etiology Malassezia spp. formerly Pityrosporum Pathogenesis when there is excessive heat and moisture, there may be increased growth of Malassezia spp. compared with other normal flora Associated conditions seborrheic dermatitis Prognosis often recurs Presentation Symptoms asymptomatic inability to tan in affected areas Physical exam discolored macules and patches affecting the trunk, neck, and face lesions have overlying fine scale variable color pale yellow white hypopigmentation hyperpigmentation yellowish brown Studies KOH preparation skin scrapings mixed with KOH short multibranching hyphae and budding cells “spaghetti and meatballs” appearance Wood lamp examination affected areas fluoresce yellow to yellow-green < 50% sensitivity Differential Vitiligo affected areas also fluoresce under Wood lamp lesions are depigmented Pityriasis alba affected areas do not fluoresce under Wood lamp Treatment Medical topical treatment indication avoid systemic effects of oral medications first-line therapy drugs zinc pyrithione 1% shampoo selenium sulfide 2.5% shampoo often also used for prophylaxis ketoconazole shampoo sulfur salicylic acid shampoo azole creams oral antifungals indication if disease is widespread or refractory to topical treatment drugs itraconazole fluconazole Complications Areas of discoloration may be permanent