Application value of polymerase chain reaction combined with probe-based in the diagnosis of pediatric Mycoplasma pneumoniae pneumonia and drug resistance mutation / 中华实用儿科临床杂志

ABSTRACT

Objective To evaluate the value of polymerase chain reaction (PCR) combined with probe detection method in diagnosis of Mycoplasma pneumonia (MP) pneumonia (MPP) in children and to analyze the factors influencing the diagnostic accuracy,and to identify the rate of MP mutation for drug resistance and the involving factors.Methods Two hundred and twenty-five children with MPP hospitalized in the Department of Respiratory Medicine,Beijing Children's Hospital,Capital Medical University between June 2015 and March 2016 were enrolled in this study.Nasopharyngeal swab samples from the participants within 24 hours of admission were detected by using PCR combined with fluorescence probes for MP-DNA and macrolide-resistant mutations.The information of age,sex,clinical symptoms,course of disease,duration by admission,the history of macrolide treatment and the increase or decrease of quadruple or more serum MP antibody titer were extracted from medical records within 4 weeks of treatment,which received further correlation analysis with the detection rate of MP-DNA and the drug resistance mutation.Results The sensitivity of the MPP by using the method of PCR combined with fluorescence probes was 80.4％ (181/225 cases),while the specificity was 98.0％ (99/101 cases).The MP-DNA positive rate for patients with double MP antibody 4 times increased during treatment was 88.8％ (71/80 cases),which was significantly higher than that of patients with antibody titer ≥1 ∶ 160 [75.9％ (110/145 cases)],and the difference was sigmficant(x =5.443,P =0.020).The positive rate of MP-DNA of patients had no obvious association with gender,age,and disease duration and macrolide treatment history before admission.Macrolide-resistant mutation rate of MP-DNA was 85.1％ (154/181 cases),macrolide-resistant mutation rate of MP for patients finishing one course of macrolide treatment when admission(89.6％)was higher than that of the patients without using macrolide and the patients treated with macrolide but not finishing one course of treatment (71.9％ and 86.6％),and the significant difference among the three groups was observed(x2 =4.454,P =0.035).Conclusions PCR combined with fluorescence probe for MP-DNA detection has a high accuracy for the diagnosis of MPP,and the overall mutation rate is high,suggesting that the clinical treatment of MPP needs to be adjusted according to drug resistance in children.