Clinical Significance of Pleural Effusion in Mycoplasma pneumoniae Pneumonia in Children

The clinical significance of pleural effusion in Mycoplasma pneumoniae (MP) pneumonia in children has not yet been elucidated. Herein, we investigated the clinical implications of pleural effusion in children with MP pneumonia. Overall, 150 children with MP pneumonia transferred to a tertiary hospital were enrolled in this study. Information on their clinical, laboratory, and radiological features was retrospectively obtained from medical chart reviews. In total, 24 (16.0%) children had pleural effusion at the time of admission. The duration of fever and length of hospitalization were significantly longer in the pleural effusion group than in the non-pleural effusion group. A significantly higher proportion of individuals in the pleural effusion group had a poor response to stepwise treatment for MP pneumonia. The mean C-reactive protein, lactate dehydrogenase, and aspartate aminotransferase levels were significantly higher in the pleural effusion group than in the non-pleural effusion group at admission. The prevalence of severe pneumonia, defined on the basis of the extent of pneumonic lesions on chest radiography, was higher in the pleural effusion group than in the non-pleural effusion group. However, there was no significant intergroup difference in the proportion of macrolide-resistant MP cases or respiratory viral coinfections. The presence of pleural effusion in children with MP pneumonia indicated a more severe clinical course and poor treatment response. The results of the present study would help in the creation of a therapeutic plan and prediction of the clinical course of MP pneumonia in children.