肌炎的临床诊断

临床分型多发性肌炎皮肌炎免疫介导坏死性肌炎肿瘤相关性肌炎CTD相关性肌炎嗜酸性粒细胞肌炎肉芽肿性肌炎局灶/结节性肌炎眶周肌炎包涵体肌炎多发性肌炎(PM)典型皮疹有诊断特异性合并ILD常见且进展快难治性皮疹考虑合并肿瘤可能皮肌炎(DM)无肌病性皮肌炎(ADM)是一组高度异质性疾病Nearlyallpatientswillpresentwithsubacuteonsetofproximalweaknessthatisverysymmetricalandinvolvesthepelvicaswellastheshouldergirdle病理：肌肉的坏死是其突出临床表现,炎性浸润可以很轻或不明显预后因病因不同而不同坏死性肌炎(NM)坏死性肌炎(NM)自身免疫性坏死性肌病药物相关坏死性肌病肿瘤相关坏死性肌病①抗SRP相关②抗HMGCR相关③无自身抗体存在坏死性肌炎(NM)坏死性肌炎(NM)坏死性肌炎(NM)IIM:CLINICALFEATURESDMPMIBMAgeatonset:Adult,childAdult50Sexpreference:FFMFamilyhistory:NoNoRareAssociationwithmalignancy:YesSlightNoCTD:YesYesYesWeakness:PDPDP=DRash:YesNoNoCK:↑↑↑,nl↑↑↑Normalor↑AdaptiveimmunesystemBcellsSubgroupingaccordingtoautoantibodyprofileseemstobeawaytounderstandmolecularpathwaysandpredicttreatmentresponseTcellsmaybeimportantinsubsetsofmyositisandCD28nullTcellsmayexplainsomeofthetreatmentresistance.SpecificityofTcellsisnotknownInnateimmunesystemTypeIIFN,HMGB1couldinteractwiththeadaptiveimmunesystemandmaydirectlyaffectmusclefibresTheimmunesysteminteractswithnon-immunemechanismsInflammatorycellsinpolymyositisanddermatomyositisCD8+TcellsCD4+TcellsBcellsArahata&EngelAnnNeurol1984SalajeghehMM&N42:576,2010PlasmacellsGreenbergSANeurol65:1782,2005,SalajeghehMM&N42:576,2010MacrophagesDendriticcellsPageGetalA&R50:199,2004Plasmacytoiddendriticcells(pDC)GreenbergetalAnnNeurol,57:664,2005TcellsBcellsCD8+CD4+MyositisspecificautoantibodiesClinicalphenotypesinadultsandchildrenAnti-synthetasesAnti-Mi-2Anti-SRPAnti-SAEAnti-MDA5Anti-p155/140TIF1gPL-12OJKSPL-7EJJo-1ZoHaAnti-p140LungdiseaseMyositisHallmarkDMCADMSevereDM(muscle,skin,softtissue)Cancer-DMSeverenecrotizingmyopathyMSAsinadultandjuveniledisease,CourtesyH.GunawardenaGunawardenaH.Rheumatology2009;48:607-12.Review.BcellActivatedTcellActivatedTcellActivatedTcellActivatedTcellBcellMemoryBcellImmunecomplexformationUptakeofautoantigenBcellactivation&differentiationPCautoantibodyproductionAPCTcellactivation&proliferationFcγReceptorBCellReceptor/AntibodyTCellReceptorMHCIIBcellepitopeTcellepitopeAdaptiveandinnateimmunesystemTh17CD28nullTcellTregpDCIFNaCourtesyK.AmaraHMGB1MuscleweaknessEarlyphasewithoutinflammatoryinfiltratesClassicaltimeofdiagnosisChronicphasewithoutinflammatoryinfiltratesDiagnosisofPM/DMImmunosuppressivetreatmentObservationsfromlongitudinalstudies–MHCclassIinmusclefibersMHCclassIinmusclefibersMHCclassIinmusclefibersDiseaseonset?Healthyindividual?Regeneratingmusclefiberexpressinghistidyl-tRNAsynthetaseMusclefiberInflammatorycellIFN-a,bVirusHistidyl-tRNAsynthetase?LymphnodesTrauma/HypoxiaBTTTTBBBBTTTTBBBTTTAPCsTBTcellBcellPlasmacytoidDCHypothesismyositisandanti-Jo-1Anti-Jo-1TIFN-a,bCD28nullTRef:CasciolaRosenJEM2005IL-1aIL-1a,bIL-15HMGB1ABCDDM(A&B):pDCproducingTypeIIFN(IFNαandβ)dendriticcells(DC)PM/IBM(C&D):mDCproducingTypeIIIFN,namelyIFNγGreenbergetal.,2005,Ann.Neurol.Greenbergetal.,2007,MuscleNerve.plasmacytoidDC(pDC)andmyeloidDC(mDC)PM:IMMUNOPATHOGENESISImmunopathologyCD8+cytotoxicmemoryTcellsinvadenonnecroticmusclefibersMHCclassIexpressiona/b-Tcells,oligoclonalTCRgenerearrangementsantigen-drivenresponseEosinophilicmyofasciitisGranulomatousmyopathyDM:OVERLAPSYNDROMESSSandMCTDMusclebiopsyvariableincidenceofabnormalbiopsyfiberatrophy:generalizedortypeIItypicalDMpathologyunspecificinflammatorymyopathyperimysialdenseconnectivetissuevascularabnormalitiesvasculitisMRI在PM/DM中的应用价值确定诊断累及范围及活动度评估确定病变阶段确定理想的活检部位疗效评估了解全身肌肉受累情况肌肉外PM/DM相关疾病鉴别诊断MRI在PM/DM诊断中的应用MRI检查序列T1WT2WSTIRT2WfsDWIT1Wfs+C1.看TR、TET2WI：长TR（2000毫秒）、长TE（50毫秒）T1WI：短TR（﹤800毫秒）短TE（﹤20毫秒）STIR:长TR、长TE、有TI2.看脂肪T1W/T2W高信号STIR低信号3.看水T1W低信号T2W高信号；STIR高信号T1WT2WSTIR如何区分T1WI、T2WI、STIRT2WSTIRT1WMRI在PM/DM诊断中的应用T1WT2WSTIRT1Wfs+CMRI在PM/DM诊断中的应用T1WT2WSTIRT1Wfs+C脂肪高中、高低低水低高高低钙化低低低低正常肌肉低低低均匀轻度强化肌肉水肿区等或略低高高斑片状强化肌肉脂肪浸润区高中、高低低PM/DM肌肉MRI表现1.肌肉炎性水肿（局灶性分布）STIRSTIRT2WT1WPMPM/DM肌肉MRI表现1.肌肉炎性水肿（局灶性分布）T1WDWISTIRT2WPM/DM肌肉MRI表现1.肌肉炎性水肿（散在性分布）STIRSTIRT1WPM/DM肌肉MRI表现T1WT2WSTIRSTIR1.肌肉炎性水肿（弥漫性分布）DMPM/DM肌肉MRI表现T1WSTIRT2.皮下软组织炎性水肿（弥漫性）PM/DM肌肉MRI表现DMT1WT2WSTIRSTIR2.皮下软组织炎性水肿（弥漫性）PM/DM肌肉MRI表现2.皮下软组织炎性水肿（局限性）PM/DM肌肉MRI表现STIR3.肌筋膜炎STIRPM/DM肌肉MRI表现T1WSTIRSTIRT2W4.脂肪沉积、肌肉萎缩PM/DM肌肉MRI表现正常肌肉T1W病变肌肉T1W4.脂肪沉积、肌肉萎缩PM/DM肌肉MRI表现T1WFST1W4.脂肪沉积、肌肉萎缩PM/DM肌肉MRI表现T1WSTIR脂肪浸润合并水肿PM/DM肌肉MRI表现DMT1WT2WSTIRSTIR皮下及肌肉炎性水肿、肌肉萎缩脂肪浸润MRI新技术在PM/DM应用1.T2MAPSTIRT2MAPMRI新技术在PM/DM应用2.DWISTIRDWIMRI新技术在PM/DM应用2.DWIMRI新技术在PM/DM应用4.MRS-1HMRI新技术在PM/DM应用4.MRS-1HSubhawongTK,WangX,MachadoAJ,etal.1Hmagneticresonancespectroscopyfindingsinidiopathicinflammatorymyopathiesat3T.InvestRadiol,2013;48(7):509-16.MRI新技术在PM/DM应用5.灌注加权像（PWI)MRI新技术在PM/DM应用6.肌肉纤维束示踪肿瘤相关性肌病肿瘤最常见于肌病发生的1-3年内出现(60%)肿瘤与肌病同时发生肿瘤出现在肌病之前DM(白种人)：与卵巢癌、肺癌、胰腺癌、胃癌有较强相关性，PM(白种人)：非霍奇金淋巴瘤、肺癌和膀胱癌较多见国内IIM:各种类型的肿瘤绝多数患者都只发生一种肿瘤，但也有同时或先后出现两种或三种肿瘤的情况概念散发性包涵体肌炎是一组50岁以上人群最常见的慢性、进行性肌纤维变性伴随炎细胞浸润为主要改变的骨骼肌疾病发病率在4.9-13/100万之间，而50岁人群的发病率在3.95/10万。占国外特发性炎性肌肉病的30%AmatoAA,BarohnRJ.Inclusionbodymyositis:oldandnewconcepts.JNeurolNeurosurgPsychiatry.2009;80:1186-93.发病机制肌纤维变性炎细胞浸润AskanasV,EngelWK.Sporadicinclusion-bodymyositis:Conformationalmultifactorialageing-relateddegenerative