Investigation of relationship between serum cd74 levels and mif gene polymorphism with clinical features in patients with ankylosing spondylitis

Objective: The primary aim of this study was to compare the CD74 antigen levels of ankylosing spondylitis (AS) patients with those of healthy controls. The secondary aim was to explore the distribution of polymorphisms of Macrophage Migration Inhibitory Factor (MIF) 173 G/C in both AS patients and control group. The last aim of this study was to investigate a possible relationship between CD74 antigen levels and polymorphism of MIF 173 G/C . Methods: 79 AS and 82 healthy blood donors who applied to Gaziantep University Physical Medicine and Rehabilitation Department / Rheumatology polyclinic were included in the study. Clinical and demographic characteristics of the patients were questioned and recorded. CD 74 antigen level and MIF 173 G / C polymorphism were investigated in the patient and control group. Bath AS Disease Activity Index (BASDAI), Bath AS Metrology Index (BASMI), Bath AS Functional Index (BASFI), Bath AS Radiology Index (BASRI), day and night evaluated Visual Analogue Scale (VAS), and Ankylosing Spondylitis Quality of Life (ASQOL) Scale scores were calculated and recorded. Results: There were no statistically significant differences between patient and control groups with respect to their age, gender, and body mass index. CD74 antigen levels were significantly low in AS patients when compared to those of the controls. Median CD74 of the patient group, 1.17(0.93-2.1), was significantly lower than that of the controls, 2.16(1.6-4.41). There were no correlations found between the CD74 antigen levels and BASDAI, BASMI, BASFI, BASRI, VAS and ASQoL scores. It was found that the number of patients with C allele was higher than that of the controls, however, the difference was not statistically significant. There were no correlations found between genotypes and BASDAI, BASMI, BASFI, BASRI, VAS and ASQoL scores. A comparison of the median CD74 with respect to HLA B-27 status and genotypes of the patients and controls showed no statistically significant difference. Conclusion: It was found that the CD74 antigen levels of AS patients were significantly lower than that of the control group. Accordingly, it is believed that CD74 is a parameter which can be used in AS diagnosis. Although it was found that the C allele frequency of polymorphisms of MIF 173 G/C was higher in the patient group, the difference was not statistically significant. Furthermore, there was no statistically significant relationship between CD74 antigen levels and polymorphisms.