Laboratory findings and treatment response in patients with HLA-B27 positive and HLA-B27 negative spondyloarthropathy

Introduction and Aim: Spondyloarthropathies (SpA) constitute a group of diseases, including ankylosing spondylitis (AS), radiographic axial spondyloarthritis (r-axSpA), non-radiographic axial spondyloarthritis (nr-axSpA), as well as arthritis forms associated with psoriasis and inflammatory bowel diseases. SpAs can manifest with symptoms such as inflammatory back pain (related to sacroiliitis or spondylitis), enthesitis, oligoarthritis, anterior uveitis, psoriasis, and inflammatory bowel disease. Human leukocyte antigen (HLA) class 1 allele HLA-B27 is associated with the development of spondyloarthropathies, including ankylosing spondylitis and reactive arthritis. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) are commonly used acute phase reactants as indicators of systemic inflammation. In our study, 50 patients with Spondyloarthropathy, classified as HLA-B27 positive and HLA-B27 negative, were examined. Clinical and laboratory findings before and after treatment were evaluated. Clinical assessment was performed based on the BASDAI scales. Laboratory investigations included sedimentation rate, CRP, white blood cell count (WBC), platelet count, hemoglobin (Hgb), alanine transaminase (ALT), and aspartate transaminase (AST). The primary objective of our study is to retrospectively analyze the laboratory findings and treatment response in HLA-B27 positive and HLA-B27 negative patients with Spondyloarthropathy. The analysis aims to compare the laboratory values of patients before and after treatment. Materials and Methods: A retrospective evaluation was conducted on the laboratory findings, disease activity, and HLA-B27 genetic results of 50 SpA patients followed at the Department of Internal Medicine, Immunology Division, Faculty of Medicine, Karadeniz Technical University, Trabzon, Turkey. Findings: Out of the 50 patients included in the study, 12 (24%) were female, and 38 (76%) were male. Of the patients, 37 (74%) were HLA-B27 negative, and 13 (26%) were HLA-B27 positive. In the MRI imaging, 24 patients (49%) had findings consistent with sacroiliitis, while 25 patients did not have sacroiliitis-compatible findings. MRI results could not be obtained for one patient. The chief complaint at the time of presentation was lower back pain in 19 patients (38%) and limb pain was more prominent in 31 patients (62%). The mean BASDAI score before treatment was 4.78. Conclusion: There was no significant decrease in the BASDAI score before and after treatment in both HLA-B27 positive and negative patients. No significant changes were observed in ESR, CRP, and platelet values. A decrease in the BASDAI score was observed in HLA-B27 negative patients before and after treatment. The lack of a significant decrease in the BASDAI score before and after treatment in both HLA-B27 positive and negative patients was associated with the uneven distribution of patients, with 37 in the HLA-B27 negative group and 13 in the positive group. The insignificant p-value is thought to be due to the unequal distribution of patients in both groups. In future studies, enrolling an equal number of patients in both groups is planned. Keywords: Spondyloarthropathies, Ankylosing Spondylitis, HLA-B27