Beyond Pneumonia: Nonspecific and Extrapulmonary Manifestations of Mycoplasma pneumoniae Infection in Children

Abstract

Mycoplasma pneumoniae is a well-recognized cause of respiratory infection in children, but its clinical spectrum extends beyond the lungs. Extrapulmonary manifestations may occasionally precede respiratory symptoms or dominate the presentation, making the diagnosis more difficult. This narrative clinical review focuses on nonspecific and extrapulmonary manifestations reported in pediatric patients, including neurological, mucocutaneous, hematological, cardiovascular, hepatic, gastrointestinal, and musculoskeletal complications. Relevant literature published between 2000 and 2026 was reviewed using PubMed/MEDLINE, Scopus, and Google Scholar. Most reported extrapulmonary manifestations appear to be immune-mediated, although direct microbial effects and vascular or prothrombotic mechanisms may contribute in selected cases. Clinical presentations range from prolonged fever and nonspecific systemic symptoms to severe complications such as encephalitis, myocarditis, hemolytic anemia, mucocutaneous disease, and thromboembolic events. Diagnosis can be challenging because respiratory symptoms may be minimal, while laboratory and microbiological findings are not always straightforward to interpret. Positive microbiological findings should be interpreted in the clinical context because currently available tests cannot reliably distinguish active infection from asymptomatic carriage. Recognition of extrapulmonary manifestations is critical for timely diagnosis and appropriate management in pediatric practice. M. pneumoniae should be considered in children with otherwise unexplained extrapulmonary manifestations, particularly when there is a history of recent respiratory illness.