Melasma/Chloasma/PIH

ICD-11

ED60.1

Synonyms

Post-inflammatory hyperpigmentation (PIH), chloasma (hormonal), melasma.

Epidemiology

Frequent disorder. Mostly appearing due to physical, chemical or drug induced changes of melanocyte activity or destruction and melanophage accumulation. Chloasma in women during and after pregnancy or under hormonal contraception. Especially in dark skinned people (South America, Southeast Asia).

Definition

Troublesome hyperpigmentation of the face, mostly in females.

Aetiology & Pathogenesis

Physical (UV-light), chemical (cosmetics), hormones (women, pregnancy, contraceptives) and genetic disposition (coloured skin/phototypes III - VI) play an important role.

Signs & Symptoms

Irregular, «dirty-gray», muddling, poikilodermic, cosmetically compromising, circumscribed hyperpigmentation of the face, forehead and neck. In chloasma distribution in the middle line/front of the lower trunk. PIH may occur elsewhere depending on causative agent or trauma.

Localisation

Face, predominantly cheeks and zygomatic arch, forehead,neck and other areas.

Classification

Depending on aetiology: physical, chemical, hormonal, post-traumatic.

Laboratory & other workups

Not needed. Sometimes endocrinological examination.

Dermatopathology

Usually not needed. In order to determine the localisation of pigment a biopsy may sometimes be recommended. Increased deposits of melanin in basal keratinocytes and in melanophages of the dermis.

Course

Chronic; depends on aetiology.

Complications

Cosmetically compromising; psyche, decreased quality of life index.

Diagnosis

Typical clinical pictures.

Differential diagnosis

Phototoxic dermatitis; (exogenous) ochronosis. Pigmentary skin deposits (minocycline).

Prevention & Therapy

Strict UV-protection. Topical bleaching, using a combination of hydroquinone, tretinoin (Vit A- acid) and hydrocortisone (Kligman-formula). Azelaic-acid. Superficial chemical peeling and laser treatment have a limited effect and success depends on skin area and depth of pigmentation. Skin pastilla grafts.

6.3.3 Melasma/Chloasma/PIH