Melasma

From Anvita Health Wiki

Contents 1 Introduction 2 Etiology 3 Epidemiology 4 Pathology 5 Genetics 6 Clinical-manifestations 7 Differential-diagnosis 8 Management 9 More General Terms 10 Additional Terms 11 References

Introduction

• From the Greek 'a black spot'. An acquired light or dark brown hyperpigmentation in a sun-exposed area, most frequently on the face.

Etiology

• sun exposure
• pregnancy
• contraceptive hormones
• medications - dilantin
• idiopathic

Epidemiology

• common
• more common in Asian, Middle Eastern, Indian, South American individuals
• 90% females, most premenopausal
• more frequent in sunny areas

Pathology

• increase in production & transfer of melanosomes to keratinocytes
• possible increase in number of melanocytes
• may be dermal, epidermal or mixed

Genetics

• 30% of patients have family history of melasma [2]

Clinical-manifestations

• macular hyperpigmentation evolving over weeks
• light or dark brown, blue-gray or black

• dermal melasma is blue-gray, similar to tattoo

• generally symmetric
• sun-exposed skin

• generally on face

Differential-diagnosis

• post- inflammatory hyperpigmentation

Management

• strictly a cosmetic problem
• only epidermal melasma is responsive to therapy [2]
• combination therapy more effective than monotherapy [2]
• 3% hydroquinone in combination with topical tretinoin
• azelaic acid or kojic acid
• prevention

• opaque sunblock - titanium dioxide or zinc oxide
• SPF 30 ineffective

More General Terms

• skin disease (dermatologic disorder, dermatopathy, dermatosis)
• granuloma

Additional Terms

• hyperpigmentation

References

1. Color Atlas & Synopsis of Clinical Dermatology, Common & Serious Diseases, 3rd ed, Fitzpatrick et al, McGraw Hill, NY, 1997, pg 300-301
2. Goodheart HP & Mamis S Skin disorders in women of color Disorders of pigmentation - melasma Women's Health in Primary Care 8:473, 2005

melasma (chloasma, mask of pregnancy)