Clinical characteristics of Mycoplasma pneumoniae pneumonia in different pediatric age groups

Abstract

Background: Mycoplasma pneumoniae is an important pathogen of childhood community-acquired pneumonia. While M. pneumoniae pneumonia generally occurs in school-aged children, recent studies have recognized its burden in young children, yet the difference in clinical feature has not been clarified. The aim of this study is to compare the clinical characteristics of M. pneumoniae pneumonia between children of different age groups. Methods: We reviewed medical records of children with M. pneumoniae pneumonia who were treated at the Seoul National University Hospital from January 2010 to December 2015. Patients were divided into 3 age groups: group 1, <2 years

group 2, 2 to <5 years

group 3, 5 to <18 years. The clinical manifestations and laboratory findings of children in each group were compared. Results: Of the 411 children with M. pneumoniae pneumonia, 39 (9.5%) patients were in group 1, 150 (36.5%) patients in group 2, and 222 (54.0%) patients in group 3. Respiratory viruses were more commonly co-detected in group 1 (51.9%) than group 3 (23.4%, P = 0.002). The fever duration of children in group 1 was shorter than that in group 2 (7 days vs. 10 days, P = 0.021) and group 3 (7 days vs. 10 days, P = 0.006). Group 1 presented with shorter fever duration even though fewer children (56.4%) were treated with macrolide compared to children in group 2 (87.3%) and group 3 (92.8%) (P < 0.001). Additionally, the initiation of macrolide from fever onset was late in group 1 when compared to group 2 (P = 0.016) and group 3 (P = 0.004), and the treatment duration of group 1 was shorter than group 2 (P = 0.042). On initial auscultation, wheezing was more frequently heard in group 1 compared to the other two groups (P < 0.001). However, when children without respiratory virus co-detection were separately analyzed, there was no significant difference in wheezing among the three age groups. Group 1 children with co-detected respiratory virus tended to have lower rate of rise in antimycoplasma antibody titer than those without respiratory virus co-detection (57.1% vs. 90.0%, P = 0.25). Conclusions: M. pneumoniae pneumonia in young children tended to present with shorter duration of fever, frequent wheezing and co-detection with respiratory viruses. Further studies are needed to elucidate the role of M. pneumoniae as a sole pathogen for pneumonia, one of the co-detected pathogens, or asymptomatic colonizer in viral pneumonia in young children.