A study of community-acquired in Yantai, China.

INTRODUCTION

Community-acquired pneumonia (CAP) is a global disease responsible for a large number of deaths, with significant economic impact. As diagnostic tools have increased in sensitivity, understanding of the etiology of CAP has begun to change. is one of the major pathogens causing CAP. Macrolides and related antibiotics are first-line treatments for . Macrolide resistance has been spreading for 15 years and now occurs in worldwide. We undertook the first study on macrolide resistance of in Yantai. This may be helpful to determine the appropriate therapy for CAP in this population.

OBJECTIVE

To investigate the rate and mechanism of macrolide resistance in Yantai.

METHODS

Pharyngeal swab samples were collected from adult CAP patients. Samples were assayed by polymerase chain reaction (PCR) and cultivated to test for . Nested PCR was used to specifically amplify 23S rRNA gene fragments containing mutations, and amplicons were analyzed by CE-SSCP for macrolide resistance mutations. Results were confirmed by sequencing. Twenty-seven strains of were isolated and the activities of nine antibiotics against were tested .

RESULTS

Out of 128 samples tested, 27 were positive for . Mycoplasma 100% macrolides resistance to . The mechanism of macrolides resistance was A2063G point mutation in the sequence directly binding to macrolides in the 23S rRNA V domain The mean pyretolytic time for the fluoroquinolone group was 4.7 ±2.9 d, which was significantly shorter than 8.2 ±4.1 d for the azithromycin group.

CONCLUSIONS

Macrolides are not the first-line treatment for respiratory tract infections in Yantai.