聚合酶链反应(PCR)检测幽门螺杆菌cag A基因  

Direct PCR for identification of cag A gene of Helicobacter pylori

作　　者：齐志宏[1] 刘振元[1] 秦伟[1] 褚娅[1] 

机构地区：[1]中国医学科学院.中国协和医科大学北京协和医院检验科,北京100032

出　　处：《中国实验诊断学》2003年第5期410-411,共2页Chinese Journal of Laboratory Diagnosis

摘　　要：目的　探讨应用PCR直接测定胃粘膜标本中幽门螺杆菌cagA基因。方法　不需细菌培养 ,直接从胃粘膜标本中提取幽门螺杆菌DNA ,选择合适的引物及条件进行PCR ,通过琼脂糖电泳来确定标本中的cagA基因。结果　每例cagA阳性的标本在 191bp的位置有一条清晰的电泳带。 19例胃溃疡患者中cagA阳性 16例 ,阴性 3例。 15例健康人血清对照 ,cagA阳性 3例 ,阴性 12例。该法敏感性 84 .2 % ,特异性 80 %。同时进行快速尿素酶实验 ,发现 17例阳性标本中PCR方法 16例阳性 (94 .1% ) ,2例快速尿素酶实验阴性标本PCR阴性。二者没有显著差异 (χ2 =0 ,P >0 .0 5 )。结论　应用PCR直接测定胃粘膜标本中幽门螺杆菌cagA基因方法简单 ,快速 ,灵敏度和特异性较高。Objective To explore the method of using PCR to assay directly cag A gene of Helicobacter pylori.Methods None culture,direct abstract DNA of Helicobacter pylori from the sample of gastric mucosa , and by PCR, the primer and conditions, to amplify cag A gene.Results The cag A-positive has a clear electrophoretic stripe of 191bp.In our hospital , assaying cag A gene from gastric mucosa of 19 patients with gastric ulcer(male 12,female 7), 16 cases are PCR-positive. Simultanously assaying cag A of serum of 15 healthy controls(male 10,female 5), 3 cases are PCR-positive,12 cases are PCR-negative.The sensitivity of the PCR is 84.2%,The specificity is 80%.To compare the results of the PCR with rapid urease test of Helicobacter pylori: finding out 16 cases of 17 positive of rapid urease test are PCR-positive (94.1%),2 of 2 negative cases of rapid urease test are PCR-negative. There are no significant difference between the two methods(χ 2=0,P> 0.05 ).Conclusion It is simple, rapid and more sensitive and specificity by PCR to amplify directly cag A gene of Helicobacter pylori from gastric mucosa.

关 键 词：聚合酶链反应 PCR 检测 幽门螺杆菌感染 CAG A基因 

分 类 号：R446.5[医药卫生—诊断学]