Procalcitonin most sensitive and specific systemic marker in differentiating septic from aseptic arthritis

Results:

Using multiple logistic regression, bacteremia (OR 6.75 ± 5.75) was determined to be the greatest predictor of SA. On linear regression, concomitant bacteremia (coef 3.07 ± 0.87), SA (coef 2.18 ± 0.70), and the presence of pseudogout crystals (coef 1.80 ± 0.83) on microscopy predicted an increase in PCT. Using a PCT cutoff of 0.25 ng/mL yields a sensitivity of 91.7% and specificity of 55.2% for predicting SA; however, the ideal cutoff in our series was 0.32 ng/mL with a sensitivity of 79.2% and specificity of 72.4%. PCT was superior to the white blood cell count, erythrocyte sedimentation rate, and C-reactive protein in the area under the receiver-operating characteristic curve analysis.

Procalcitonin seems to be the most sensitive and specific systemic marker in differentiating septic from AA.

Reference:

West K, Almekdash H, Fisher J, Rounds AD, Murphree J, Simpson J. Procalcitonin as a Predictor of Septic Knee Arthritis: A Retrospective Cohort Study. J Am Acad Orthop Surg Glob Res Rev. 2023 Jan 9;7(1):e22.00261. doi: 10.5435/JAAOSGlobal-D-22-00261. PMCID: PMC9831185.

Keywords:

West K, Almekdash H, Fisher J, Rounds AD, Murphree J, Simpson J. Procalcitonin, Predictor, Septic, Knee, Arthritis, Retrospective Cohort Study, J Am Acad Orthop Surg Glob Res Rev.