Risk factors affecting severe pneumococcal pneumonia in children: a retrospective study

Abstract Objective To identify risk factors for severe Streptococcus pneumoniae pneumonia (SPP) in children, and to analyze the characteristics of co-infection, drug resistance, and vaccine serotype distribution. Methods A retrospective cohort study was conducted. The clinical data, laboratory parameters, etiological co-infections, antibiotic resistance, and vaccine serotype coverage rates were collected and compared between the severe SPP and non-severe SPP groups. Results A total of 203 children were included in the study. Univariate analysis revealed that the median age, fever duration, CRP, PCT, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were significantly higher in the severe SPP group than in the non-severe SPP group (P < 0.05). Multivariate analysis identified older age, elevated NLR, and longer fever duration as independent risk factors for severe SPP. The area under the receiver operating characteristic (ROC) curve for the combined prediction of the three was 0.802, the highest. Severe SPP combined with mycoplasma pneumoniae (MP) infection rate was higher (P < 0.05), but the incidence of wheezing was instead lower in this subgroup (P < 0.05). Antibiotic resistance profiles did not differ significantly between groups, with the highest resistance rate to erythromycin (over 90%) and the lowest to penicillin (1.4%–1.8%). The vaccination rate with the 13-valent pneumococcal conjugate vaccine (PCV13) was low in both groups (9.1% severe vs. 4.7% non-severe). There were no significant differences in PCV13 serotype coverage (58.2% severe vs. 55.4% non-severe). Conclusion Higher median age, elevated NLR, and longer duration of fever are independent risk factors for severe SPP in children, and their combination effectively predicts disease severity. Co-infection with MP may increase the risk of severe disease but alter the clinical phenotype. Clinical treatment should focus on the high macrolide resistance, and penicillins may be preferred. Currently, the vaccination rate for PCV13 is low, and increasing this rate is the primary task to prevent this disease. Clinical trial number Not applicable.