Serum interleukin-23 level in rheumatoid arthritis patients: Relation to disease activity and severity

Abstract

Aim of the workThe aim of this study was to evaluate interleukin-23 (IL-23) level in the sera of rheumatoid arthritis (RA) patients and to determine its relation with disease activity and severity. Patients and methodsThis study was carried out on 40 RA patients and 40 healthy control subjects. All patients were subjected to full history taking, thorough clinical examination, radiological and laboratory investigations including C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), anti-cyclic-citrullinated peptide (anti-CCP) antibodies. Serum IL-23 was measured by enzyme-linked immunosorbent assay. Disease activity score (DAS-28) and rheumatoid arthritis severity scale (RASS) were assessed. ResultsPatient's mean age was 43.3 ± 10.4 years and they were 37 females and 3 males. The mean disease duration of the patients was 4.98 ± 4.1 years (1–15 years) with a mean DAS-28 of 4.8 ± 1.2 (2.4–7.6) and RASS of 41.1 ± 16.9 (16.7–85). The mean IL-23 serum level was significantly higher in RA patients (67.6 ± 39.2 pg/ml) compared to the control (37.7 ± 15.6 pg/ml) (p < 0.001). There were significant correlations between IL-23 levels with the DAS-28 (r = 0.35, p = 0.02), RASS (r = 0.31, p = 0.04), CRP (r = 0.39, p = 0.02), ESR (r = 0.45, p = 0.004), RF (r = 0.48, p = 0.002) and anti-CCP antibodies (r = 0.35, p = 0.04). At a cut-off value of 45 (pg/ml), IL-23 had a sensitivity of 77.8% and a specificity of 75% for detection of active disease and at 43.5 pg/ml the sensitivity was 88.2% and specificity 83.3% for occurrence of physical damage. ConclusionIL-23 could be a useful marker for disease activity in RA. Its correlation with RASS suggested that IL-23 might be a therapeutic target for prevention of disability.