Melasma

Snapshot

  • A Middle Eastern 30-year-old woman comes to her obstetrician for recent darkening of her facial skin and neck. She is 34 weeks pregnant with her first baby. This has never happened to her before. Exacerbating factors include prolonged sun exposure, after which her face seems to darken more. She denies any pruritus or pain. She has no significant past medical history. Physical exam reveals symmetric macular eruption of hyperpigmentation on her face. Her laboratory values are all normal.

Introduction

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  • Also known as chloasma
  • Brown, hyperpigmentation of face and neck
  • Epidemiology 
    • more commonly in women of darker skin tones
    • often associated with high levels of estrogen
      • pregnancy
        • “mask of pregnancy”
      • oral contraceptive pills
  • Etiology
    • unknown
  • exacerbated by sun exposure

Presentation

  • Symmetric macular (flat) eruption of brown hyperpigmentation
    • typically well-defined borders
  • Common in the forehead, upper lip, chin, malar eminences, and neck
  • Non-erythematous, non-inflammatory

Evaluation

  • Diagnosis based on clinical exam and history

Differential Diagnosis

  • Post-inflammatory hyperpigmentation
  • Lentigines

Treatment

  • Topical hydroquinone (bleaching cream)
    • with or without tretinoin cream
  • Sun avoidance and sunscreen use
  • Cessation of contraceptives

Prognosis, Prevention, and Complications

  • Usually fades over months after pregnancy or cessation of contraceptives