抗MDA5抗体阳性炎性肌病患者的临床特征
目的：
本研究的目的是评估抗黑素瘤分化相关基因5（MDA5）抗体阳性的炎性肌病患者的临床特征以及发病前后抗MDA5抗体滴度的变化。
方法：
收集-年期间在本院新诊断的例PM/DM患者，采用MESACUP抗MDA5检测法，在诊断时和治疗后采用ELISA法检测血清抗MDA5抗体水平。分析抗MDA5抗体水平与临床表现、实验室数据及死亡率之间的关系。
结果：
与抗MDA5抗体阴性的患者相比，抗MDA5抗体阳性的患者更容易出现皮炎，无肌病性DM、间质性肺病和快速进展性间质性肺病，血清铁蛋白显著升高，肌酸激酶和醛缩酶明显降低，ANA阳性率明显低（?1∶）及出现抗胞浆型阳性。
在2例患者发病前检查抗MDA5抗体滴度：一例显示2年前低滴度的抗体阳性，两者在发病时均表现出滴度升高。
与治疗后死亡的患者比较，存活者抗MDA5抗体滴度显著降低，但两组治疗后2个月比较无统计学差异。
结论：
本研究观察到在大多数患者治疗开始后，抗MDA5抗体滴度最初有所降低，包括死亡病例，这表明抗MDA5抗体可能不是治疗DM患者的有效标志物。
原文
Clinicalcharacteristicsandchangeintheantibodytitresofpatientswithanti-MDA5antibody-positiveinflammatorymyositis
Abstract
OBJECTIVE:
Theaimofthisstudywastoevaluatetheclinicalcharacteristicsofpatientswithanti-melanomadifferentiation-associatedgene5(MDA5)antibody-positiveinflammatorymyositis,andthechangeinanti-MDA5antibodytitresbeforeandafteronset.
METHOD:
ForPM/DMpatients,newlydiagnosedinourhospitalwithintheperiod-,serumanti-MDA5antibodylevelsweremeasuredatdiagnosisandaftertreatmentbyELISAusingtheMESACUPanti-MDA5test.Therelationshipsbetweenanti-MDA5antibodylevelsandclinicalmanifestations,laboratorydata,andmortalitywereexamined.
RESULT:
Comparedwithpatientswhowereanti-MDA5antibodynegative,thosewhowereantibodypositivedemonstratedmorefrequentdermatitis,clinicallyamyopathicDM,interstitiallungdiseaseandrapid-progressiveinterstitiallungdisease,aswellassignificantlyhigherserumferritin,significantlylowercreatinekinaseandaldolase,andsignificantlylessfrequentANA(?1:)andanti-cytoplasmicpatternofANAstainingpositivity.Anti-MDA5antibodytitreswereexaminedbeforediseaseonsetintwopatients;oneshowedantibodypositivitywithlowtitres2yearsearlier,whilebothexhibitedincreasedtitresatonset.Anti-MDA5antibodytitresdeclinedsignificantlylessinsurvivorsthaninnon-survivorsaftertreatment;however,therewasnosignificantdifferencebetweenthetwogroupswhentheratewas
