I-metabolism ye-pigment yesikhumba engaqhelekanga - i-chloasma

I-Chloasma sisiphazamiso esixhaphakileyo sokufumana umbala wolusu kwinkqubo yonyango. Iyenzeka kakhulu kubasetyhini abakwiminyaka yokuzala, kwaye inokubonwa nakumadoda angaziwayo. Ibonakaliswe nge-pigmentation ye-symmetrical ezihlathini, ebunzi nasezidleleni, ubukhulu becala obufana namaphiko ebhabhathane. Umthubi okhanyayo okanye omdaka okhanyayo, onzima omdaka omnyama okanye omnyama okhanyayo.

Phantse bonke abantu abancinci bobuhlanga kunye nobuhlanga banokusiphuhlisa esi sifo, kodwa iindawo ezinokuvezwa kakhulu kwe-UV, ezinje ngeLatin America, Asia, kunye neAfrika, zinezehlo eziphezulu. Uninzi lwezigulane zihlakulela isifo kwi-30 kunye ne-40s, kwaye iziganeko kwi-40- kunye ne-50 yeminyaka ubudala i-14% kunye ne-16%, ngokulandelanayo. Abantu abanolusu olukhanyayo bakhula kwangethuba, abantu abanolusu oluntsundu bakhula kamva, nasemva kokuyeka ukuya exesheni. Uphando oluvela kubantu abancinci baseLatin America lubonisa iziganeko ze-4% ukuya kwi-10%, i-50% kubasetyhini abakhulelweyo kunye ne-10% kumadoda.

Ngokwendawo yosasazo, i-melasma inokwahlulwa ibe ziintlobo ezi-3 zeklinikhi, kubandakanywa phakathi kobuso (kubandakanya ibunzi, i-dorsum yempumlo, izihlathi, njl. njl.), i-zygomatic kunye ne-mandible, kwaye izinga lezehlo li-65%, i-20 %, kunye ne-15%, ngokulandelelanayo. Ukongezelela, ezinye izifo zesikhumba ze-idiopathic, ezifana ne-idiopathic periorbital skin pigmentation, zicingelwa ukuba zidibene ne-melasma. Ngokwendawo yokubeka i-melanin eluswini, i-melasma inokwahlulwa ibe yi-epidermal, i-dermal kunye neentlobo ezixubileyo, phakathi kwazo uhlobo lwe-epidermal lolona hlobo luqhelekileyo, kwaye uhlobo oluxubeneyo lunokwenzeka kakhulu.isibane Woodluncedo ekuchongeni iintlobo zeklinikhi. Phakathi kwabo, uhlobo lwe-epidermal lubomvu olukhanyayo phantsi kokukhanya kwe-Wood; uhlobo lwe-dermal luyingwevu ekhanyayo okanye eluhlaza okwesibhakabhaka phantsi kweliso leze, kwaye umahluko awubonakali phantsi kokukhanya kweWood. Ukuhlelwa ngokuchanekileyo kwe-melasma kunenzuzo ekukhetheni unyango kamva.