Abstract:

[Abstract] Objective  To study the characterization and molecular mechanisms of macrolide-resistant mycoplasma pneumoniae (MP) in children hospitalized with pneumonia in Tianjin. Methods  A total 237 of alveolar lavage fluid specimens were collected from children with pneumonia hospitalized in Tianjin children’s hospital from October 2010 to December 2011. The DNA of them was extracted. The genomic fragments of the strains were amplified by using polymerase chain reaction (PCR) method with specific primers. The positive strains were selected randomly to be amplified with nest PCR method. The amplifiable production was electrophoresised and purified and the 23 S rRNA gene sequences were sent to sequencing. The results of sequencing were compared with the sequence of MP M129 to detect the mutations. Results  Among 237 specimens，129 samples were MP positive after detecting by PCR with the primers. The positive rate was 54.43% (129/237). Of the 50 strains that were selected to sequence, 4 strains and the standard strains were completely same. The other 46 strains showed A-to-G transition at position 2063. There was no other site of mutation. The percentage of macrolide-resistant was 92% (46/50). Conclusion  The macrolide-resistance in mycoplasma pneumoniae is serious in Tianjin. The major molecular mechanism is A-to-G transition at position 2063 of the 23 S rRNA domain Ⅴ.

Key words: pneumonia, mycoplasma RNA, ribosomal, 23Smacrolidesgene expression polymerase chain reactionchild TIANJIN, 聚合酶链反应