Indirect Particle Agglutination Antibody Testing for Early Diagnosis of Mycoplasma pneumoniae pneumonia in children

Abstract

목 적 : 이 연구의 목적은 항체 검사를 어느 시기에 검사해야 마이코플라스마 폐렴을 가장 적절하게 진단을 내릴 수 있는지를 파악하기 위함이다.방 법: 2011년 6월부터 2011년 10월까지의 한양대학교병원에서 진단받은 206 명의 폐렴 환아들을 대상으로 후향적으로 분석하였다.결 과:마이코플라스마 폐렴으로 진단받은 160명의 평균 연령은 5.4세이었다. 마이코플라스마 간접입자 응집항체의 측정을 위한 혈청 획득 시간은 마이코플라스마 항체가가 1:640 이상인 혈청들과(8.58일) 1:640 미만인 혈청들(5.44일) 사이에서 통계학적으로 유의한 차이가 있었다(P <0.001).결 론 : 본 연구의 결과는 폐렴 환아에서 증상 시작일로부터 8일 전에 획득한 마이코플라스마 항체가가 음성이면 확진을 위해 반복 검사가 필요한 것으로 보였다. 이 제안으로 마이코플라스마 폐렴에서 최적의 진단을 내릴 수있게 도움을 줄 수 있을 것이다.Objectives: Outbreaks of pneumonia caused by Mycoplasma pneumoniae (MP) occur every 3-4 years in Korea, most recently in 2011. The aim of our study was to determine the optimal time to perform indirect particle agglutination antibody assays to improve early diagnosis of MP pneumonia in children.Methods: A database of 206 pediatric patients treated for pneumonia at the Hanyang University Hospital from June to October 2011 was analyzed retrospectively for demographic characteristics and laboratory test results.Results: Among the 206 patients treated for pneumonia during the study period, there were 160 children (mean age, 5.44years) diagnosed with MP pneumonia, who were studied further. The mean age of these MP pneumonia patients was 5.44years. Antibody titers increased with increasing time between symptom onset and the collection of serum collection: MP titers were <1:640 for sera collected after 5.44 days and titers 1:640 for those collected ≥ after 8.58 days; P<0.001). Antibody titers were considered positive when they reached ≥1:640. In 42 MP pneumonia patients in whom there was a four-fold or greater increase in titer between successive serum samples, the optimal cut-off time-point for distinguishing between the initial and second titer groups was 7.5 days after the onset of symptoms (sensitivity, 90.5%; specificity, 92.9%).Conclusions: Negative MP antibody titers earlier than 8 days after the onset of symptoms in children with pneumonia may require repeating to confirm the diagnosis. This finding could optimize diagnosis and result in better therapeutic outcomes of MP pneumonia in children.