Polymerase chain reaction 양성 소아 마이코플라스마 폐렴에서 혈청 IgM enzyme-linked immunosorbent assays의 진단적 가치

• Published in: Allergy asthma & respiratory disease pp. 248 - 254
• Main Authors: 이혜진, 이윤태, 김경훈, 양은애, 김환수, 전윤홍, 윤종서, 김현희, 김진택
• Format: Journal Article
• Language: Korean
• Published: 대한 소아알레르기 호흡기학회 30.09.2018
• Subjects: 소아과학
• ISSN: 2288-0402; 2288-0410
• DOI: 10.4168/aard.2018.6.5.248

Purpose: Mycoplasma pneumoniae (MP) is a common cause of community-acquired pneumonia (CAP) in children. MP Serum IgM and polymerase chain reaction (PCR) are the methods that enable early diagnosis in patients with MP pneumonia. The objective of this study was to investigate the clinical value of serum MP-specific IgM antibodies in PCR-positive MP pneumonia for the early diagnosis of MP pneumonia in children with CAP. Methods: Out of 129 patients with lower respiratory tract infection aged over 3 years, 90 CAP children were enrolled in the study. Throat swab MP real-time PCR and serum enzyme-linked immunosorbent assays (ELISA) IgM antibodies were performed. A positive rate of MP PCR and serum IgM, the level of IgM index, clinical features, and laboratory findings were analyzed. Results: MP PCR was positive in 57 cases. Longer fever duration before admission (P<0.001), higher rates of lobar or segmental pneumonia (P=0.048), unilateral infiltration (P=0.038), and extrapulmonary symptoms (P=0.049) were associated with MP PCR-positive pneumonia. Serum IgM index was significantly higher in MP PCR-positive pneumonia them in MP PCR-negative pneumonia (3.9±3.0 vs. 0.8±1.3, P<0.001). Using MP PCR as a gold standard, the sensitivity, specificity, positive predictive value and negative predictive value of serum IgM were 85.5%, 82.1%, 91.4%, and 71.9%, respectively. The area under the curves for serum IgM index was 0.892, and the ROC analysis indicated that an optimal cutoff value of 1.05 for serum IgM provided the highest sensitivity and specificity interestingly (83.9% vs. 85.7%, P<0.001). Conclusion: Serum IgM ELISA has useful diagnostic value in PCR-positive MP pneumonia. Applying an IgM index cutoff of 1.05 improves diagnostic accuracy. KCI Citation Count: 0