Alarming serum antiprotease levels in axial spondyloarthritis

Abstract

Objectives: The objective was to assess the serum levels of secretory leukocyte protease inhibitor (SLPI) and elafin in individuals diagnosed with axial spondyloarthritis (AxSpA) and analyze their diagnostic significance and correlation with disease activity.

Patients and methods: The case-controlled, cross-sectional study was conducted between August 2021 and April 2023. Sixty patients diagnosed with AxSpA (n=60) were classified according to imaging results as nonradiographic AxSpA (nr-AxSpA [n=30]; 15 males, 15 females; median age: 30 years; range, 27.6 to 34.1 years) and radiographic AxSpA (r-AxSpA [n=30]; 19 males, 11 females; median age: 33 years; range, 30.6 to 38.1 years), forming two patient groups (the nr-axSpA and r-axSpA groups). A total of 30 age- and sex-matched healthy controls (16 females, 14 males; median age: 33 years; range, 29.2 to 37.1 years) were included. Demographic data, laboratory, and clinical characteristics of the participants were recorded.

Results: There was no significant difference between SLPI and elafin serum levels in the disease groups. SLPI and elafin levels in AxSpA and nr-AxSpA groups were significantly higher compared to the control group (p<0.05). Based on receiver operating characteristic analysis, the diagnostic values of both parameters were found to be significant in the Ax-SpA and nr-AxSpA groups (p<0.05). There was no significant correlation between serum levels of SLPI and elafin and disease activity parameters. Significant positive correlations were found between SLPI and elafin in both the nr-AxSpA (p<0.05, r=0.870) and r-AxSpA (p<0.05, r=0.725) groups.

Conclusion: The levels of SLPI and elafin were found to be significantly elevated in patients with AxSpA, particularly in those with nr-AxSpA, compared to the control group. Therefore, SLPI and elafin can be used as therapeutic biomarkers for the diagnosis of AxSpA and nr-AxSpA. However, no relationship was found with disease activity.

Citation: Kul A, Tüzün Z, Çelik M. Alarming serum antiprotease levels in axial spondyloarthritis. Arch Rheumatol 2024;39(2):285-293. doi: 10.46497/ ArchRheumatol.2024.10466.

The study protocol was approved by the Atatürk University Faculty of Medicine Clinical Research Ethics Committee (date: 15.04.2021 no: 56). Atatürk University Scientific Research Projects Coordination Unit supported our study within the framework of scientific research projects (04.08.2021/TSA-2021-9500). The study was conducted in accordance with the principles of the Declaration of Helsinki.

A written informed consent was obtained from each patient.

Idea/concept, literature review: K.A., C.M.; Design, control/supervision, analysis and/or interpretation, critical review, references and fundings, materials: K.A., T.Z., C.M.; Data collection and/or processing: K.A., T.Z.; Writing the article: K.A.

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

The authors received no financial support for the research and/or authorship of this article.

The data that support the findings of this study are available from the corresponding author upon reasonable request.