anti-Mycoplasma pneumoniae IgM index ; Children ; Mycoplasma pneumoniae pneumonia
Abstract
Purpose: Mycoplasma pneumoniae (MP) has become a very important pathogen in childhood community-acquired pneumonia and usually detected with a immunological method. There had been a few studies for relationship of its antibody titer with the clinical features, so this study has been done to know it. Methods: I collected the informations of MP pneumonia patients who had been admitted and diagnosed with Chorus anti-Mycoplasma Pneumoniae IgM index method at the Department of Pediatrics, Yongin Severance Hospital, Yongin, Korea from September 2010 to December 2011. I divided the patients to group A(>5.0) and group B (≤5.0 and ≥1.1) by index value and compared them. Results: There were 99 cases for group A(55 boys and 44 girls) and 170 cases(83 boys and 87 girls) for group B. The mean ages for group A and group B were 4.4±3.0 years old and 5.0±3.0 years old respectively(P=0.167). There was no difference for sex ratio(P=0.287). The frequent clinical findings for group A and B were cough(100.0% versus 96.5%, P=0.088), sputum(96.0% versus 90.6%, P=0.105), fever(89.9% versus 90.0%, P=0.979), and rale(71.8% versus 61.2%, P=0.080). Chest radiographic infiltration had been found in 94 cases(95.0%) of group A and 154 cases(90.6%) of group B(P=0.198). Group A had longer durations of pre-admission fever(3.7±3.5 days versus 2.8±2.2 days, P=0.007), cough(6.7±5.3 days versus 5.2±5.5 days, P=0.030), sputum(6.7±5.6 days versus 4.7±5.4 days, P=0.014), more frequent vomiting(17.2% versus 8.8%, P=0.041), urinary ketone(10.1% versus 3.5%, P=0.028) and pyuria(18.2% versus 9.4%, P=0.038), more peripheral blood platelet counts (324,180.7 ± 96,279.3/μL versus 269,117.5±91,421.2/μL, P=0.00004), faster erythrocyte sedimentation rate (29.9±15.1 mm/hr versus 26.3±13.7 mm/hr, P=0.048) than group B. The admission durations were 4.2±1.5 days for group A and 4.2±1.4 days for group B(P=0.912). Conclusion: The Chorus anti-Mycoplasma pneumoniae IgM index titer is related with the initial clinical severity, but it does not predict the short-term prognosis. Continuous monitoring and study for it should be carried on to know its relevance to long-term prognosis.