Bacterial pathogens in sputum of children with community-acquired pneumonia, unexpected results: a single hospital-based study

Background Community-acquired pneumonia (CAP) is one of the most important causes of mortality and morbidity in children worldwide. Identification of the microbial etiology in childhood CAP is impeded by difficulties in obtaining the proper samples. Limited data have been reported on bacterial pathogens that cause childhood CAP in Saudi Arabia. Objectives The authors aim to investigate the bacteriological causes of childhood CAP in Saudi Arabia and the value of serum biomarkers in the identification of bacterial CAP. Materials and methods A retrospective analysis of the electronic data of children with CAP aged 1 month to 14 years who were admitted between January 1, 2017 and December 31, 2019 was carried out. Demographic, clinical, laboratory, radiological, and sputum culture data were extracted. Results A total of 163 children with documented bacterial sputum culture results were identified; 43 (26.4%) had positive sputum. Staphylococcus aureus was the most frequently isolated organism in children with bacterial CAP (37.2%), followed by Klebsiella pneumonia (30.2%), streptococcus pyogens (14%), pseudomonas (14%), enterococci (2.3%), and streptococcus pneumonia (2.3%). A total leukocyte count of 11 000/mm3 has 60% sensitivity and 67% specificity for the prediction of positive bacterial sputum culture. An absolute neutrophil count of 7000/mm3 and C-reactive protein of 30 mg/L have low sensitivities of 36% and 38%, but high specificities of 78% and 80% in predicting positive bacterial sputum culture, respectively. Conclusion S. aureus and Klebsiella pneumonia are the most common bacteria that cause CAP in children in Saudi Arabia, with a lower prevalence of streptococcus pneumonia. Serum biomarkers such as total leukocyte count, absolute neutrophil count, and C-reactive protein have adequate specificity to identify patients with positive bacterial sputum culture.