【摘要】 目的　探讨快速检测结核分枝杆菌异烟肼 (INH)耐药基因型的分子药敏方法。方法　用聚合酶链反应 单链构象多态性 (PCR SSCP)检测了 3 0株INH敏感菌株及 3 0株耐药株的katG基因 ,随后用SSCP方法鉴定扩增产物有无突变 ,以结核分枝杆菌H3 7Rv作对照。结果　所有INH敏感株均观察到katG基因扩增产物 ,3 0株INH耐药株中 2 8株观察到katG基因扩增产物。以H3 7Rv标准株为对照 ,3 0株敏感株SSCP带谱与对照相同 ;2 8株INH耐药株中 13株与对照相同 ,15株有不同程度的差异。与药敏试验比较 ,PCR SSCP检测INH耐药结核菌的敏感性为 5 7% ,特异性为 10 0 %。结论　多数结核分枝杆菌耐INH是由于katG基因突变所致 ,用PCR SSCP筛选突变株可达到快速检测结核分枝杆菌INH耐药基因型的目的更多还原

【Abstract】 Objective One of the main mechanisms of isoniazid (INH) resistance is catalase peroxidase katG gene mutation of Mycobacterium tuberculosis . Polymerase chain reaction (PCR) and singlestrand conformation polymorphism (SSCP) technique is a simple, rapid method for detecting gene mutation. In this study, the katG gene mutation associated with isoniazid resistance was detected by PCR SSCP technique. Methods Thirty isoniazid susceptible M.tuberculosis clinical isolates and 30 isoniazid resistant isolates were analysed by PCR SSCP technique, with Mycobacterium tuberculosis H 37 Rv reference strains as control group. The detection method involved amplification of the isoniazid resistance region of katG gene by PCR and the identification of mutations of the amplification products by SSCP analysis. Results Amplification was observed in all clinical isolates except two isoniazid resisant isolates. Thirty isoniazid susceptible clinical isolates and M.tuberculosis H 37 Rv displayed identical SSCP patterns. About twenty eight isoniazid resistant clinical isolates, fifteen isolates showed PCR SSCP patterns different from that of H 37 Rv, and 13 isolates displayed the same patterns as H 37 Rv. Around fifty seven percent of isoniazid resistant clinical isolates showed mutation or deletion of katG gene by SSCP analysis. Conclusion The changes of katG gene are associated with isoniazid resistance. PCR SSCP technique will be useful to rapidly screen gene mutation of isoniazid resistant M.tuberculosis .更多还原