nemoci-sympt/DERMATOLOGIE/pigmentace-pokozky/chloasma-melasma/popis-synonyma
Synonyma
- Pregnancy mask
- Těhotenské skvrny [1]
- Liver spots [3]
- Uterine chloasma
- Chloasma gravidarum
- Chloasma virginum [3]
Popis
- Brown or gray-brown patches
- Most people get it on their
- Cheeks, bridge of their nose,
- Forehead, chin,
- Above their upper lip [1]
- Can appear on other parts of the body that get lots of sun
- Forearms
- Neck [1]
- Some may experience darkening of
- Existing freckles
- Areolas (nipples)
- Moles
- Dark line down the center of the abdomen
- Known as linea nigra [1]
- Hypermelanosis of sun-exposed areas
- Symmetric hyperpigmented macules
- Can confluent or punctuate [2]
- Melanogenesis dysfunction
- Results in localized, chronic acquired hypermelanosis of the skin [3]
- Usually improves in the winter and worsens in the summer (or immediately after intense sun exposure [4]
- Frequence of facial topographies affected by melasma Topography %
- Zygomatic 84
- Supralabial 51
- Frontal 50
- Nasal 40
- Parotid 30
- Mentonian 29
- Glabellar 25
- Temporal 24
- Mandibular 18 [4]
- Reduction in its prevalence, in the intensity of lesions with age [4]
- Attenuation of pigmentation with treatment [4]
Epidemiologie
- Melasma occurs in all ethnic and population groups
- Higher prevalence among more pigmented phenotypes
- East Asians (Japanese, Korean and Chinese)
- Indian, Pakistani, Middle Eastern
- Mediterranean-African
- Hispanic-Americans
- Brazilians [4]
Nepal
- 2008 with 546 dermatological melasma patients
- 4th most frequent diagnosis
- 1st most commonly reported pigmentary dermatosis
Saudi Arabia
- Analyzed data from 1076 dermatology patients
- Pigmentary changes as the 4th most common dermatosis [4]
Washington, DC
- 2,000 dermatological patients of black origin
- 3rd most commonly-cited skin disorders were pigmentary problems other than vitiligo
- Majority had a diagnosis of postinflammatory hyperpigmentation
- Followed in frequency by melasma [4]
Brazilian states
- 2010 population-based study
- 1500 adults were surveyed for pigmentation disorders
- Main cause of demand for dermatological care
- 23.6% of men
- 29.9% of women [4]
- Survey of 57,343 diagnoses at dermatological consultations in Brazil by the Brazilian Society of Dermatology (BSD) in 2006
- Melanodermias (among them, melasma)
- 3. largest group of diseases in dermatological practice
- 8.4% of all complaints
- Prevalence 5.9% - 9.1% in the different regions [4]
- 2013 population-based study
- 515 adult employees of the University Campus of Botucatu, Sao Paulo State University, SP (Brazil)
- Melasma was identified in 34% of women and 6% of men [4]
- Large miscegenation of the Brazilian population
- Rather tropical climate of the country
- Authors estimate that 15-35% of adult Brazilian women are affected by melasma [4]
- Multicenter study involving 953 patients from three different Brazilian regions
- 13% had skin type II
- 36% had skin type III
- 40% had skin type IV
- 10% had skin type V [4]
Iran
- Population-based survey of 855 Iranian women in the city of Ardebil in 2002
- Melasma was identified in 39.5% of respondents
- 9.5% were pregnant women [4]
India
- Prevalence among paddy field workers in India reached 41%
USA
- Arab population resident in Detroit (USA)
- 14.5% of the sample had melasma
- 56.4% complained primarily of alterations in skin tone [4]
- Latino population resident in Texas (USA)
- Prevalence of melasma was 8.8%
- 4.0% of respondents reported past occurrence of melasma [4]
Tunisia
- 188 women
- 14% had skin type III
- 45% had skin type IV
- 40% had skin type V [4]
