PCR及RT-PCR检测咽拭子标本肺炎支原体的比较

Comparision of clinical diagnostic value between PCR and TaqMan RT-PCR for Mycoplasma pneumoniae in throat swabs

目的应用聚合酶链反应(PCR)与实时taqMan荧光定量PCR(RT-PCR)检测咽拭子标本中的肺炎支原体DNA(Mp-DNA),比较2种方法检测结果的临床诊断价值。方法随机选取临床儿科门诊患儿566例,包括临床治诊Mp感染患儿106例和临床疑似Mp感染患儿460例,分别采用PCR法和RT-PCR法检测,以临床治诊Mp作为参照标准,采用χ2检验评定2种检测方法诊断的灵敏度和特异度,比较2种检测方法对Mp的诊断价值。结果 566份受检患儿的咽拭子标本中,PCR法检测阳性45例(7.95%)(临床治诊Mp感染患儿5例,临床疑似Mp感染患儿40例),RT-PCR法检测阳性175例(30.92%)(临床治诊Mp感染患儿95例,临床疑似Mp感染患儿80例)。RT-PCR法检测咽拭子Mp-DNA诊断Mp感染的敏感度显著高于PCR法(敏感度RT-PCR 89.62%,PCR 4.72%,χ2=146.322,P<0.05),特异度与PCR法的差异无统计学意义(特异度RT-PCR 82.60%,PCR 91.30%,χ2=3.331,P>0.05)。结论应用RT-PCR法检测咽拭子中的Mp-DNA对儿童Mp感染的诊断价值优于应用PCR法检测咽拭子中的Mp-DNA,其中应用RT-PCR检测对Mp感染患儿的早期诊断有更大的临床价值。

To compare the clinical diagnostic value between PCR and RTPCR for M. pneumoniae in swab, we performed both PCR and RTPCR assays analysis for M. pneumoniae DNA on a total of 566 samples of throat swab from 106 pediatric children with M. pneumoniae and in whom M. pneumoniae was suspected. Among the 566 pediatric children, there were 45（7.95%） PCRpositive specimens and 175 （30. 92%） RTPCRpositive specimens. In the 106 pediatric children with M. pneumoniae, 5 were positive for PCR, and 95 were positive for RTPCR. In the 460 pediatric children with symptom of M. pneumoniae, 40 were positive for PCR, and 80 were positive for RTPCR. The sensitivy of RtPCR for M. pneurnoniae detection appeared to be better than that of PCR. （sensitivity ： RT- PCR 89.62 %,PCR 4.72 x^ 2 = 146. 322, P=0. 000）, but there was no significant difference in the specificity between RTPCR and PCR （specifitivity： RT- PCR 82. 60 %, PCR 91.30%, 2 =3. 331, P=0. 068）. It is concluded that the TaqMan based RT PCR assay is a rapid, sensitive and specific method for the detection of M. pneumoniae in throat swabs of children in early period of diagnosis.