Early diagnosis of septic arthritis using synovial fluid presepsin: A preliminary study

Therapeutic outcomes for septic arthritis vary greatly depending on the span of time between disease-onset and surgery. The most important factor is making an early and definitive diagnosis; however, some cases may be difficult to diagnose. We investigated presepsin, a biomarker of sepsis, to determine whether or not presepsin in synovial fluid would be useful for the diagnosis of septic arthritis. We selected 18 patients with septic arthritis including periprosthetic joint infections (SA group) and 28 patients with osteoarthritis (OA group). We measured the concentrations of synovial fluid presepsin, blood presepsin and procalcitonin (PCT) in the two groups. We compared the sensitivities and specificities of synovial fluid presepsin, blood presepsin and PCT. Synovial fluid and blood presepsin and blood PCT were all significantly higher in the SA group. Synovial fluid presepsin exhibited both 100% sensitivity and 100% specificity in the SA group, which were higher rates than those for blood presepsin and PCT. We found that synovial fluid presepsin is markedly elevated in case of septic arthritis, and therefore, it has potential as a new biomarker of septic arthritis.