Investigation on Serum Levels of Interleukin-18 and Interleukin-6 in Patients With Dermatomyositis and Polymyositis

摘要

Background:Dermatomyositis(DM)andpolymyositis(PM)arecommonformsofidiopathicinflammatorymyopathywhicharecharacterizedbymuscleinflammationwithanunknowncause.Immunecellsinfiltratemyofibrilsandendomysialcapillaries,whichleadstodamageofmusclefibersthroughtheproductionofhumoralfactorsanddifferentcytokines.Objectives:IncreasedIL-18andIL-6serumlevelshavebeenreportedinavarietyofautoimmunediseases,includingrheumatoidarthritisandinflammatoryboweldisease.ThepurposeofthisstudywastoevaluateIL-18andIL-6serumlevelsinDMandPMpatientscomparedtoahealthycontrolgroup.PatientsandMethods:Inthiscross-sectionalstudy,15patientswithDM,5patientswithPM,and20healthycontrolsubjectswererecruited.ThelevelsofserumIL-18andIL-6inpatientsandcontrolgroupsweremeasuredbyusingELISAassay.BloodtestsweretakentodeterminethelevelsofC-reactiveprotein(CRP)andcreatinekinase(CK)andweremeasuredbystandardmethods.StatisticalanalyseswereperformedusingtheMann-WhitneyU-testwithanon-GaussianpopulationusingSPSS19software.Results:IL-18levelsweresignificantlyhigherinDMpatientsandPMpatientsbeforetreatmentcomparedtohealthycontrolsubjects(P=0.001,P=0.01,respectively).TherewerenosignificantdifferencesbetweenDMandPMpatientsbeforetreatmentwithhealthycontrolsforIL-6serumlevels(P=0.51,P=0.43,respectively).Conclusions:SerumIL-18contributestotheimmunopathogenesisofDMandPMandwouldbeausefulmarkerforthediagnosisandtreatmentofdiseases.IL-6hasalesspivotalroleinthepathologyofDMandPM.