Macrolide-Resistance of Mycoplasma Pnuemoniae in Respiratory Tract Infection in Children / 实用儿科临床杂志

ABSTRACT

Objective To investigate the mycoplasma pneumoniae(MP) infection of the respiratory tract infection in children,the macrolide-resistant situation and resistance mechanism of MP. Methods The cultured throat swab specimens were obtained from 80 pediatric outpatients with respiratory tract infection from Dec.2008 to Mar.2009 in Beijing friendship hospital.The 23S rRNA gene of throat swab specimens and positive-cultured specimens were amplified using nested-PCR,and the products were further verified by electrophoresis and DNA sepuencing,which were collected from the outpatients.The specimens were divided into 2 groups depending on the findings of the gene sequencing whether they had gene mutationsensitive and resistance group.The DNA sequence of samples were compared to the sequence of MP reference strain in genbank in order to findout MP drug resistant gene.The differences in macrolids therapy were investigated between 2 groups before the throat swab obtained.The drug resistance rates were compared between outpatients and inpatients. Results Thirty-two throat swab specimens were proved to be MP by direct nested-PCR,and 8 throat speeimens were proved to be MP by isolation and culrures.Total 33 cases(including 1 was positive-culture but nagative-direct PCR) were proved to be MP positive.Sixteen were identical to the M129 standard sequence,and 17 had point mutation in gene of 23S rRNA V region.Ten had A to G mutation at position 2063,3 had A to G mutation at position 2064,2 had A to G mutation at position 2067,1 had G to A mutation at position 2062,1 had A to T mutation at position 2063.There was no significant difference between the sensitive and resistance group in whether had macrolids before the throat swab obtained(P =0.909).And there was no significant difference in MP drug resistance rate between outpatients and inpatients(P =0.459). Conclusions The major mutation were A2063G and A2064G,and A2063T,A2067G,G2062A were newly found mutation points which were possibly related to macrolids resistance.