Which inflammatory marker is more reliable in diagnosing acute septic arthritis in the pediatric population?

Background: The present study aimed to investigate diagnostic values of C-reactive protein (CRP), white blood cell (WBC), erythrocyte sedimentation rate (ESR), neutrophil to lymphocyte ratio (NLR), and the platelet to lymphocyte ratio as possible indirect inflammatory markers in children with septic arthritis (SA) for diagnosis process.

Methods: The medical records of pediatric patients with SA who underwent debridement surgery between February 2005 and November 2018 were obtained from the hospital records. A total of 59 children with SA and 60 age- and gender-matched healthy controls were enrolled in the study. Hemograms parameters including WBC count, neutrophil count, lymphocyte count, hemoglobin, platelet count, CRP, ESR, NLR, and platelet to lymphocyte ratio. Biochemical parameters including alanine transaminase, aspartate aminotransferase, blood urea nitrogen, creatinine, glucose, and albumin were investigated and compared between both groups.

Results: Fifty-nine patients, 30% female (n: 18) and 70% male (n: 41), who had received operations for SA were included in the study. The mean age of the patients was 7.1 (range 6 days to 15 years) years and mean follow up 56.6 (12-140) months. No significant differences were observed in any biochemical parameters between the groups. However, a significant difference was found between the septic arthritis and the control group in all hemogram parameters.

Conclusions: Although the sensitivity and specificity of the NLR are lower than CRP, ESR, and WBC which are most commonly used inflammatory parameters in diagnosis process of septic arthritis, NLR may be useful in confirming the diagnosis in the clinical practise, with an optimum diagnostic cut-off value of 4.05.