Which statements describe melasma?

• A. Brown patches on face, particularly on cheeks, forehead, and upper lip; more common in women, often during pregnancy; treated with hydroquinone or tretinoin
• B. Vesicular lesions on hands; treated with acyclovir
• C. Papulonodular trunk lesions; isotretinoin
• D. Pigmented nails; antifungals

Answer: (A)

Melasma is a common acquired hyperpigmentation of the face driven by sun exposure and hormonal factors, especially in women during pregnancy or on estrogen-containing therapies. It presents as symmetric, brown to gray-brown patches on sun-exposed facial areas such as the cheeks, forehead, and upper lip. The key idea is that hormonal changes stimulate increased melanin production by melanocytes, producing these patches. Treatment centers on sun protection and depigmenting therapies, with topical agents like hydroquinone (a tyrosinase inhibitor) and tretinoin helping to lighten the patches by reducing melanin production and speeding turnover of pigmented skin. Other statements describe conditions that affect different areas or presentations (vesicular hand lesions suggest herpes, papulonodular trunk lesions suggest acne, pigmented nails suggest a fungal infection), which are not melasma.