ALOPECIA專(zhuān)業(yè)知識(shí)課件

ALOPECIAWHATISALOPECIA?ITISABSENCEORLOSSOFHAIRFORMSOFALOPECIAAREATA-BALDSPOTSPATCHYHAIRLOSSTOTALIS-COMPLETELYBALDORWITHLITTLEVISIBLEHAIRONSCALPUNIVERSALIS-NOVISIBLEHAIRONBODYCICATRICIAL-SCARRINGHAIRLOSSCurrentevidencesuggeststhatalopeciaareataiscausedbyanabnormalityintheimmunesystem.Thisparticularabnormalityleadstoautoimmunity.Asaresult,theimmunesystemattacksparticulartissuesofthebody.Inalopeciaareata,forunknownreasons,thebody'sownimmunesystemattacksthehairfolliclesanddisruptsnormalhairformation.Biopsiesofaffectedskinshowimmunecellsinsideofthehairfollicleswheretheyarenotnormallypresent.Whatcausesthisisunknown.Alopeciaareataissometimesassociatedwithotherautoimmuneconditionssuchasallergicdisorders,thyroiddisease,vitiligo,lupus,rheumatoidarthritis,andulcerativecolitis.Sometimes,alopeciaareataoccurswithinfamilymembers,suggestingaroleofgenesandheredity.ALOPECIAAREATAALOPECIAAREATAIsalopeciaareatahereditary?

Yes,heredityplaysarole.Inoneoutoffivepersonswithalopeciaareata,someoneelseinthefamilyalsohasit.Thosewhodevelopalopeciaareataforthefirsttimeaftertheageofthirtyyearshavelesslikelihoodthatanotherfamilymemberwillhaveit.Thosewhodeveloptheirfirstpatchofalopeciaareatabeforetheageofthirtyhaveahigherpossibilitythatotherfamilymemberswillalsohaveit.ALOPECIATOTALISAlopeciatotalisisthelossofallheadhair.Itscausesareunclear,butitisanautoimmunedisorder.Stressissometimesthoughttobeacontributortothehairlosscausedbyalopecia,howevermanypeopleleadingrelativelystress-freeliveshaveexperiencedthesymptoms.ALOPECIATOTALIS(CONT’D)Inalopeciatotalis,immunesystemcellscalledwhitebloodcellsattacktherapidlygrowingcellsinthehairfolliclesthatmakethehair.Theaffectedhairfolliclesbecomesmallanddrasticallyslowdownhairproduction.Fortunately,thestemcellsthatcontinuallysupplythefolliclewithnewcellsdonotseemtobetargeted.Sothefolliclealwayshasthepotentialtoregrowhair.ISTHEREADIFFERENCEBETWEENAREATAANDTOTALIS?Forallpracticalpurposes,afewpatchesofhairlossiscalledAlopeciaareata;whiletotalhairlossalloverthehead,includingeyebrows,eyeslashesiscalledAlopeciatotalis.Thetreatmentapproachisdifferentandtheprognosisisalsodifference.Thatis,AlopeciaAreataistreatablewithgreatsuccess,whileAlopeciatotalisisnotcurableusinghomeopathy.Steroidsmayhelpbutsuperficially.Ourexperiencesuggeststhatbyuseofsteroids,mostpatientsgetmorespotselsewhereontheskin.Steroidsdonotaddressinternalautoimmunedisorder.But,theyareveryusefulduringacuteattacks.ALOPECIAUNIVERSALISThemostadvancedforminaseriesofconditionsallrelatedtothesamedisease,AlopeciaUniversalisischaracterizedbytotalalossofbodyhair.AmemberofthegroupofhairlossconditionscalledAlopeciaAreata,theonlydifferencebetweenAlopeciaUniversalisandit'svariantsistheextentofhairloss.

ALOPECIAUNIVERSASLIS(CONT’D)Patientsareusuallyotherwisehealthy,buthavemorethyroiddiseaseandvitiligothanthegeneralpopulation.Thosewithvitiligo(patchylossofskincolor)mayalsodevelopAUintime.ManyindividualswithAlopeciaUniversalisarebornwithsomehair,butthenbeginlosingitveryquickly.Thedisorderisinheritedasanautosomalrecessivetrait.ItiscausedbyamutationinagenedubbedHRinchromosomeband8p21.2thatisthehumanhomologueofthemouse"hairless"gene--thehumanversionofthegeneinthemousethatisresponsibleforhairlessmice.

ALOPECIAUNIVERSALIS(CONT’D)Isthe"hairless"geneonlyfoundinpeoplewithAlopeciaUniversalis?Mostlikely.Basedontheknownresearch,wecansafelyassumethatonlyindividualswiththisrareandsevereformofAlopeciaAreatacarrythegene.Unfortunately,therehavenotbeenenoughstudiesdonetoverifythatthisistrueofallthoseafflicted.

ALOPECIAUNIVERSALIS(CONT”D)Asidefromgenetictendencies,thecontributingcausesofAlopeciaUniversalisarenotknown.Itisimportantthatthosewithitarecarefultoprotectthemselvesfromthesun,bacteria,andotherpotentiallyharmfulelements,asthescalp,nasalcavityandeyesarenotprotected.

AccordingtotheNationalAlopeciaAreataFoundation,otherthanthehair,nailscanalsobeaffected.Thenailinvolvementmaybelimitedtopinprickindentations,allthewaytoseveredistortionoftheentirenail.AlopeciaUniversalismaybeacuteandshort-lived,orremainpermanently.Thepossibilityofregrowthdoesremainhowever,evenforthosewith100%hairlossformanyyears.Predictingwhenregrowthmayoccurisnotcurrentlypossible.

ALOPECIAINCHILDRENHairlossinchildrenisactuallynotverycommon,howeveritissignificantenoughthatnearly2MillionchildrensufferfromatleastoneformofAlopecia(hairloss)oranotherintheUnitedStatesalone.Thegoodnewsisthatatleast60%ofchildrenwithAlopeciawill"outgrow"theconditionwithoutneedfortreatment.AswithallformsofAlopecia,areversalandcompleterestorationofhairtakestime-sometimesuptoayearormore,butforthevastmajorityofchildren,itwillspontaneouslyresolve.Thebadnewsisthat40%wonthavesuchluck,whichcanbequitefrustratingbothfortheparentsandthechildaffectedbythisoftencosmeticallyembarrassingcondition.

CHILDRENWITHALOPECIAPleasekeepinmind:hairlossinchildrenisnotduetovitamindeficiencies(unlessextrememalnutritionispresent),poorscalpcirculation,headbands,hats,orcoldweather.Diagnosisistypicallyassimpleasanevaluationoftheriskfactorsavisualexaminationofthetypeofloss,andsometestsyourdoctorcanperform.

Alopeciaisnotlife-threatening,andchildrenwhohaveitareotherwisehealthy.Whythehairfallsoutfromtherootsisstillamystery.Whatisknownisthattheconditionisnotcontagious,causedbyfoods,ortheresultofnervousness,hyperactivedisorders,orpsychologicalstress.In20%ofcasesanotherfamilymemberhasbeenaffected.Somepatientswithth