Identifying Inflammation in Knee Osteoarthritis: The Relationship of Synovial Fluid White Blood Cell Count to MRI Effusion-Synovitis

Autor: Lindsey A, MacFarlane, Kaetlyn R, Arant, Aleksandra M, Kostic, Hanna, Mass, Morgan H, Jones, Jamie E, Collins, Elena, Losina, Jeffrey N, Katz
Rok vydání: 2022
Zdroj: Arthritis careresearch.
ISSN: 2151-4658
Popis: Inflammation is a potential pain generator and treatment target in knee osteoarthritis (OA). Inflammation can be detected on MRI and by synovial fluid white blood cell count (SF WBC). However, the performance characteristics of SF WBC for the detection of synovitis have not been established.We identified records of patients seen at an academic center with a diagnosis code for knee OA, a procedural code for knee aspiration and laboratory order for SF WBC in the same encounter, as well as an MRI within 12 months of the aspiration. MRIs were read for effusion synovitis (E-S) using the MRI OA Knee Score (MOAKS). We dichotomized E-S as: 1) none or small, or 2) medium or large. We calculated the sensitivity and specificity of SF WBC, using MRI E-S (medium/large) as the gold standard. We used Youden's Index to identify the best cut-point.We included 75 patients. Mean age was 63 y.o. (SD 12) and 69% were female. The SF WBC was higher in the medium/large E-S group (median = 335, IQR =312) than in the none/small group (median = 194, IQR =272). The optimal cut-point was 242, yielding a sensitivity of 71% (95% CI 56-83%) and specificity of 63% (95 % CI 41-81%).The sensitivity and specificity of SF WBC in identifying E-S on MRI were limited. Further research is needed to better understand the association between MRI and SF measured E-S and to determine which measure more strongly relates to synovial histopathology and patient outcomes.
Databáze: OpenAIRE