From the Research
Pityriasis alba is typically diagnosed through clinical examination and dermoscopy, with key diagnostic criteria including white structureless spots, scaling, indistinct borders, and normally pigmented hairs, as identified in a recent study 1. The diagnostic process for Pityriasis alba involves several steps, including:
- Visual inspection: Look for characteristic light-colored, slightly scaly patches on the face, arms, or upper trunk.
- Patient history: Inquire about duration of symptoms, any associated itching, and history of atopic conditions like eczema.
- Dermoscopy: Utilize dermoscopy to identify specific features such as white structureless spots, scaling, indistinct borders, and normally pigmented hairs, which are consistently present in Pityriasis alba lesions 1.
- Wood's lamp examination: Sometimes used to rule out other conditions like tinea versicolor.
- Skin scraping: Rarely needed, but may be done to exclude fungal infections. No specific laboratory tests are required for diagnosis. The condition is often self-limiting and benign, requiring only reassurance and basic skincare. Treatment, if needed, focuses on moisturizing the skin and using mild topical corticosteroids for any inflammation. Pityriasis alba is believed to be a mild form of eczema, resulting in hypopigmentation due to a temporary decrease in melanin production, as suggested by histopathological studies 2, 3, 4. It's more noticeable in individuals with darker skin tones and often worsens with sun exposure, making proper sun protection important for management. The most recent and highest quality study 1 provides the most reliable diagnostic criteria for Pityriasis alba, which should be prioritized in clinical practice.