Clinical features of severe Mycoplasma pneumoniae pneumonia with pulmonary complications in childhood: A retrospective study

Incidence of severe M. pneumoniae pneumonia (SMPP) reported in China has been increasing over the last decade. We aimed to evaluate the clinical features of pediatric SMPP with pulmonary complications, according to laboratory tests and chest radiographic resolution patterns.We retrospectively reviewed 93 SMPP patients between January 2016 and February 2019, and grouped them by pneumonia pattern: pulmonary complications (63 patients) and extensive lung lesions without pulmonary complications (30 patients).SMPP patients with pleural effusion (medium or large) and necrotizing pneumonia showed longer duration of fever, high serum value of lactate dehydrogenase (LDH), d-dimer, and LDH to albumin ratio (LAR). LAR and d-dimer were associated with moderate or massive pleural effusion, and d-dimer was associated with lung necrosis. The average time of radiographic resolution in the pulmonary complication group was 12 weeks, while those with elevated d-dimer were significantly more likely to have longer time for radiographic clearance.We conclude that M. pneumoniae pneumonia in patients with pleural effusion (medium or large) or lung necrosis was more severe than those without pulmonary complications. LAR and d-dimer might be used as parameters to identify children susceptible to pleural effusion (medium or large) or lung necrosis, and longer time for radiographic clearance among pediatric patients of SMPP.