Clinical characteristics of children with septic arthritis caused by different pathogenic bacteria

Septic arthritis is a serious infectious disease in children. In this study, we retrospectively analyzed the relationship between demographics, laboratory values at presentation, reported symptoms at presentation, joint involvement, and distribution characteristics of pathogenic bacteria in 171 patients during the period of 2012-2022. The results showed that a total of 77 pathogen-positive patients were detected in the 171 patients (culture-positive rate of 45.0%), 15 categories of pathogenic bacteria, and the highest detection rates were 52 cases of <i>Staphylococcus aureus</i> (67.5%), <i>Streptococcus pyogenes</i> in 7 cases (9.1%), and <i>Streptococcus pneumoniae</i> in 5 cases (6.5%). Comparison of these three pathogens revealed that the age of the <i>Staphylococcus aureus</i> and <i>Streptococcus pyogenes</i> groups was significantly older than that of the <i>Streptococcus pneumoniae</i> group (<i>p</i> < 0.05), and that the white blood cell count (WBC) of the <i>Streptococcus pyogenes</i> group was significantly higher than that of the <i>Staphylococcus aureus</i> group (<i>p</i> < 0.05), and that the <i>Streptococcus pyogenes</i> group had a significantly higher procalcitonin (PCT), which was significantly higher in the <i>Streptococcus pneumoniae</i> group (<i>p</i> < 0.05). The results suggest that the pathogenic bacteria of septic arthritis in children are mainly <i>Staphylococcus aureus</i>, <i>Streptococcus pneumoniae</i> infection occurred more commonly in the infant stage, and <i>Staphylococcus aureus</i> and <i>Streptococcus pyogenes</i> were detected frequently in school-age children. <i>Streptococcus pyogenes</i> was found to be more pathogenic than <i>Staphylococcus aureus</i> and <i>Streptococcus pneumoniae</i>.