沙眼衣原体药物敏感性试验方法比较

Comparison of Antimicrobial Susceptibility Testing Methodologies for Chlamydia Trachomatis

目的比较3种测定沙眼衣原体对抗生素敏感性的方法。方法以微量板稀释法为基础，分别用碘染色、荧光染色和RT-PCR方法确定红霉素、阿奇霉素、克拉霉素、氧氟沙星、多西环素和四环素对E型和L3型沙眼衣原体标准株的最低抑茵浓度（MIC）。结果RT-PCR方法检出的MIC结果高出另外两种方法的1～8个稀释度。免疫荧光和碘染色法相比，后者比前者的MIC结果低1个稀释度，或者没有差别。结论就沙眼衣原体抗生素敏感性检测而言．与免疫荧光法比较，RT-PCR法较为客观，而碘染色方法则相对简便，且敏感性差别不大。

Objective To compare three methods for antimicrobial susceptibility testing on C. trachomatis. Methods Mc- Coy cells were cultured in 96 - well plates and 24 - well plates with RPMI1640 medium supplemented with 10% calf serum. When the cells came to confluency,the suspension of C. trachomatis in SPG was inoculated onto the monolayers of McCoy cells. After cen- trifugation, the supernatant was replaced with maintenance medium containing a serially twofold diluted antimicrobial agent. After incubation at 35℃ for 48 -72h ,the cultures were subjected to iodine staining,immunofluorescence staining or RT-PCR for the ex- amination of in vitro susceptibility of six antibiotics,including erythromycin, azithromycin, clarithromycin, ofloxacin, doxycycline and tetracycline, against two reference strains of C. trachomatis, E and L3. Results For all antibiotics tested, MICs resulted from RT- PCR were consistently higher than those from other two methods, and the increase in MICs ranged from 1 - 8 folds. The difference was 1 - 2 folds between iodine staining and immunofluorescence staining. Conclusion For the detection of antimicrobial suscepti- bility testing of C. trachomatis, compared with the gold standard method, RT-PCR is more objective ,while iodine staining is relatively easy to carry out.