A 30-year-old woman presents with acquired, symmetric, irregular hyperpigmented macules on the cheeks, upper lip, and forehead that worsen in summer and during her pregnancies. She takes oral contraceptive pills. Wood's lamp examination significantly accentuates the pigmentation. What does this Wood's lamp finding suggest about the melanin location, and what is the FIRST-LINE topical treatment?
- A Dermal melanin; systemic tranexamic acid
- B Epidermal melanin; triple combination cream (hydroquinone 4% + tretinoin 0.05% + fluocinolone acetonide 0.01%) ✓
- C Mixed (epidermal + dermal) melanin; Q-switched Nd:YAG laser
- D Epidermal melanin; hydroquinone 2% monotherapy only
Explanation
Melasma (chloasma) is an acquired hypermelanosis with three patterns based on Wood's lamp: epidermal type (accentuated under Wood's lamp — melanin in basal and suprabasal keratinocytes), dermal type (no enhancement — melanophages in dermis), and mixed type. Accentuation under Wood's lamp confirms epidermal melanin, which responds best to topical depigmenting agents. The Kligman-Willis triple combination cream — hydroquinone 4% + tretinoin 0.05% + fluocinolone acetonide 0.01% (Tri-Luma) — is considered the most effective first-line topical therapy, more efficacious than any single agent alone. Strict photoprotection is mandatory.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.