Mycoplasma pneumoniae and recurrent respiratory tract infection within one year after treatment in infants: Risk factors and prevalence

Abstract

Background: Mycoplasma pneumoniae pneumonia (MPP) is common in pediatric patients. Many studies showed that recurrent respiratory tract infections (RRTIs) are common in the year following treatment of MPP in infants, but the factors associated with the occurrence of RRTIs are rarely reported. Therefore, the present study aimed to identify these factors. Methods: This retrospective observational study included infants (< one year) who were clinically treated for MPP from January 2015 to December 2018. Clinical features and relevant data were collected on admission. The cases of the occurrence of RRTIs and the presence of related factors after one year of follow-up were investigated by questionnaires. The questionnaires contained the number of upper respiratory infections, tracheobronchitis, and pneumonia, the titers and course of MP-IgG and positive IgM antibody, eczema, pet ownership, interior decoration, inhaled or ingested allergens, exposure to environmental tobacco smoke, and gastrointestinal function. Independent significant risk factors for RRTIs were identified using binary logistic regression. Results: A total of 300 MPP cases were included, among which RRTIs occurred in 134 (44.7%) cases in the year following MPP treatment. Binary logistic regression analysis showed that a history of prematurity (OR = 6.336, 95% CI: 2.337-17.116, P ≤ 0.001), a history of exposure to inhaled or ingested allergens (OR = 2.527, 95% CI: 1.289-4.956, P = 0.007), and co-infection involving Chlamydia pneumoniae (OR = 2.787, 95% CI: 1.145-6.784, P = 0.024) were significantly and positively associated with RRTIs after MPP, while age (OR = 0.894, 95% CI: 0.825-0.970, P = 0.007) showed a negative correlation with RRTIs. Conclusions: RRTIs in the year following clinical treatment of MPP in infants are relatively common and significantly associated with the patient’s age, history of prematurity, history of exposure to inhaled or ingested allergens, and C. pneumoniae co-infection. Thus, these factors should be carefully assessed in pediatric MPP cases to predict the risk of RRTIs and appropriately manage the patient.