Diagnosing Septic Arthritis in the Synovial White Cell Count "Gray Zone".
Review
Overview
abstract
Differentiating septic arthritis of the pediatric hip from other causes of hip pain and effusion continues to present a diagnostic challenge for the clinician. Although septic arthritis traditionally has been reported to have a synovial white blood cell count of 75,000 cells/mm3 or greater, lower counts can be seen in this condition. In cases where a synovial sample has been obtained and the cell count falls in the intermediate range between 25,000 and 75,000 cells/mm(3), it is unclear what proportion of these cases may be truly septic hips. In this evidence-based review, we examine Heyworth et al's study focusing on the predictive value of this intermediate white cell count range in a Lyme-endemic region.