Kim Kyung Suk, Kang Jung Oak, Eun Chang Soo, Han Dong Soo, Choi Tae Yeal
Department of Clinical Pathology, Major Woman 's Hospital, Seoul, Korea.
J Korean Med Sci. 2002 Oct;17(5):599-603. doi: 10.3346/jkms.2002.17.5.599.
Among 12 clarithromycin-resistant Helicobacter pylori strains isolated in Guri, Korea, 8 showed an adenine to guanine mutation at position 2143 (formerly A2144G or E. coli 2059) in the 23S rRNA gene by the PCR-restriction fragment length polymorphism (RFLP) method. The remaining 4 strains, digested by neither BsaI nor BbsI, showed a thymine to cytosine mutation at position 2182 (T2182C) by direct sequencing of the PCR products. The T2182C mutants showed a tendency of higher levels of minimum inhibitory concentration to clarithromycin than the A2143G mutants. In conclusion, either the A2143G or the T2182C mutation was present in 100% of clarithromycin-resistant H. pylori isolates examined. The PCR-RFLP technique with restriction enzymes BbsI and BsaI was a rapid and relatively simple method to detect the clarithromycin resistance. But undigested isolates were quite frequent among our isolates (33.3%), the PCR-RFLP method with restriction enzymes BbsI and BsaI should not be used alone, and development of other rapid detection method for clarithromycin resistance is mandatory.
在韩国九里分离出的12株对克拉霉素耐药的幽门螺杆菌菌株中，通过聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法，有8株在23S rRNA基因的2143位（原A2144G或大肠杆菌2059位）发生了腺嘌呤到鸟嘌呤的突变。其余4株既不被BsaI也不被BbsI消化，通过对PCR产物进行直接测序，发现在2182位（T2182C）发生了胸腺嘧啶到胞嘧啶的突变。T2182C突变体对克拉霉素的最低抑菌浓度水平有高于A2143G突变体的趋势。总之，在所检测的对克拉霉素耐药的幽门螺杆菌分离株中，100%存在A2143G或T2182C突变。用限制性酶BbsI和BsaI的PCR-RFLP技术是检测克拉霉素耐药性的一种快速且相对简单的方法。但在我们的分离株中未消化的分离株相当常见（33.3%），不应单独使用用限制性酶BbsI和BsaI的PCR-RFLP方法，必须开发其他快速检测克拉霉素耐药性的方法。
