Clinical diagnostic value of presepsin in patients with rheumatoid arthritis complicated with bacterial infection

Abstract

Objective To investigate the clinical diagnostic value of plasma soluble leukocyte differentiation antigen 14 (presepsin) in patients with rheumatoid arthritis (RA) complicated with pulmonary bacterial infection. Methods A total of 133 patients with RA and 60 healthy controls were enrolled in this study. Fifty-eight RA patients were infected with lung bacterial infection and 75 patients were non-infected with RA. Among them, RA activity was performed in 43 patients and RA was stable in 32 patients. Chemilluminescence immunoassay was used to detect presepsin (P-SEP) in all subjects, and its correlation with inflammatory markers such as white blood cells, blood sedimentation rate and C-reactive protein was analyzed. Results The P-SEP of RA (561±142) pg/ml combined with pulmonary bacterial infection group was significantly higher than that of active RA group (378±100) pg/ml (t=8.12, P<0.01), higher than that of stable RA group (197±68) pg/ml (t=8.51, P<0.01) and healthy control group (113±9) pg/ml (t=13.75, P<0.01). There was a positive correlation between P-SEP and leukocyte count in patients with RA complicated with pulmonary bacterial infection (r=0.627, P<0.01). The degree of the disease activity was correlated with CRP (r=0.63, P<0.01), regardless of the P-SEP level (r=0.47, P=0.521). The optimal threshold value of P-SEP in diagnosing RA patients with bacterial infection was 458.9 pg/ml, with a sensitivity of 79.3% and a specificity of 81.4%. Conclusion P-SEP has an important diagnostic value for the identification of bacterial infection in RA patients, which is not related to RA disease activity. Key words: Arthritis, rheumatoid; Soluble leukocyte differentiation antigen 14; Bacterial infection