简介：Objectives:Todevelopamulti-nestedpolymerasechainreactioninanassaytodetectearlyTreponemapallidumandHaemophilusducreyiDNAintheswabsofgenitalulcers.Methods:Fourpairsofouterandinnerprimers,specifictothebasicmembraneproteingeneofTreponemapallidumandtothe16srRNAgeneofHducreyiweresynthesized.Themulti-nestedPCRwasdevelopedandappliedtodetectTreponemapallidumandHaemophilusdicreyiinclinicalswabs.Result:ThetwosamplesofstandardstrainsofHaemophilusducreyiandoneTreponemapallidumwereamplifiedandshowed309-bprRNAgeneofHaemophilusducreyiand506-bpDNAofTreponemapalidum,respectively.Outof51samplesofgenitalulcerdetected,29showedTreponemapallidumpositiveproductandnoHaemophilusducreyiDNAwasfound.Conclusion:Themulti-nestedPCRforTreponemapallidumandHaemophilusducreyicouldbeusefulforearlydetectionanddistinguishingdiagnosisbetweensyphilisandchancroid.