To assess the diagnostic values of presepsin and procalcitonin in patients with rheumatoid arthritis (RA) by identifying those with bacterial infection METHOD: During June 2014-September 2015, 126 patients with RA and 25 healthy controls were enrolled. RA patients were divided into an infection group and a non-infection group. Infection was diagnosed by clinical symptoms, microbiological or radiographic methods, and good response to antibiotics. Concentrations of plasma presepsin, serum procalcitonin, C-reactive protein (CRP), and white blood cell counts (WBC) were measured and compared in each group. The correlations with the Sequential Organ Failure Assessment (SOFA) Score and these markers were calculated.
RA patients included 26 patients in the infection group, 45 patients in the CRP-positive non-infection group (CRP > 0.3 mg/dL), and 55 patients in the CRP-negative non-infection group (CRP < 0.3 mg/dL). Levels of presepsin and procalcitonin in the infection group were highest and significantly higher than those in the CRP-positive non-infection group (presepsin 682.8 ± 158.1 pg/mL vs. 192.0 ± 12.0 pg/mL [P < 0.0001]; procalcitonin 4.052 ± 1.637 ng/mL vs. 0.120 ± 0.032 ng/mL [(P < 0.0001]). According to receiver operating characteristic curve (ROC) analysis, presepsin and procalcitonin levels appeared to have a higher diagnostic accuracy for infection than CRP or WBC. For the infection group, the SOFA Score positively correlated with the concentration of presepsin but not with that of procalcitonin.
Presepsin and procalcitonin may be useful to identify infection in RA patients. Presepsin may better reflect infection severity than procalcitonin.