Levels of YKL-40, pannexin-1, calprotectin and sialic acid in lung involvement of rheumatoid arthritis

Purpose and Hypothesis: In this study, it was aimed to determine the blood levels of YKL-40, Pannexin-1, Calprotectin and Sialic acid in RA patients with lung involvement and to investigate their relationship with disease activity. In line with the purpose of the research, two hypotheses were formed. The first of these hypotheses is "In RA patients with lung involvement, blood levels of YKL-40, Pannexin-1, Calprotectin and Sialic acid are high and are associated with disease activity". The second hypothesis of the study is "YKL-40, Pannexin-1, Calprotectin and Sialic acid blood levels are high in RA patients with lung involvement and are not associated with disease activity" Method: Our study included 18-year-olds with hemogram, sedimentation, RF, anti-CCP laboratory results, who met the 2010 ACR/EULAR criteria, were evaluated in terms of organ involvement (heart, lung, gastrointestinal system and kidney), who applied to the Internal Medicine Rheumatology outpatient clinic of Aydın Adnan Menderes University Faculty of Medicine. Patients aged 80 years were included. The patients' anamnesis, physical examination findings, sedimentation, c-reactive protein, RF, anti-CCP, kidney and liver function tests, DAS-28 scores were recorded in the case report form. During the routine outpatient control, the patients were informed about the study and their consent was obtained, and the venous blood of all groups meeting the inclusion criteria was taken into a dry biochemistry tube. When the number of patients was completed, calprotectin, Pannexin-1, Sialic acid and YKL-40 levels were obtained in serum by ELISA (enzyme-linked immunosorbent assay) method Results: A total of 154 patients, including 104 RA patients (49 with lung involvement and 54 RA patients without lung involvement), and 50 healthy controls, were included in the study. ESR and CRP were found to be statistically significantly higher in the RA lung and RA patient group, calprotectin and sialic acid in the control group, and Pannexin in the RA patient group. When biochemistry markers were compared according to threshold values between RA, RA lung and control groups, RF and anti-CCP markers were found to be statistically significantly higher in the RA lung patient group than in the RA patient group, and calprotectin marker in the control group compared to the RA and RA lung patient groups. Sialic acid was found to be statistically significantly higher in RA patients without lung involvement than in RA patients with lung involvement. Calprotectin level was found to be statistically significantly higher in the group with rheumatoid nodules than in the group without rheumatoid nodules. Conclusion: In our study, it was found that blood levels of YKL-40, Calprotectin and Sialic acid in RA lung involvement were not higher than the control group. Pannexin-1 blood levels are thought to be higher in RA patient groups than in the control group, and it is thought that Pannexin-1 may be a specific biomarker in the diagnosis of RA and disease progression. We think that a better understanding of the pathophysiology and further studies are necessary for a biomarker that researchers agree and accept. Keywords: rheumatoid arthritis, inflammation, biomarker