Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in school-aged children, but its clinical features in younger children remain poorly characterized. We conducted a retrospective cohort study of pediatric patients (<18 years) with isolated M. pneumoniae identified by multiplex PCR who presented to a tertiary children's hospital between October 2020 and February 2025. Patients with co-infections or underlying medical conditions were excluded, and clinical characteristics were compared between younger (0-5 years) and older (6-17 years) children. Among the 73 eligible patients, younger children had significantly lower oxygen saturation at presentation, more frequently required oxygen supplementation, and had higher rates of hospitalization than older children. However, other clinical findings (rate of fever, cough, pneumonia) and laboratory findings were similar between the two groups. These findings suggest that M. pneumoniae infection in younger children may be associated with a higher risk of hypoxemia despite otherwise comparable clinical features.
Kuroda et al. (Wed,) studied this question.