Abstract
OBJECTIVE: To investigate the significance of CXC chemokine ligand 10 (CXCL10) in the pathogenesis of isolated polymyalgia rheumatica (PMR). METHODS: The serum of six PMR patients diagnosed and treated at the First Affiliated Hospital of Wannan Medical College from September 2019 to December 2020 before treatment and after remission was collected, and the serum of six active rheumatoid arthritis (RA) patients and six healthy medical checkups were also collected, and protein microarray technology was used to detect 24 cytokines, including IL-6, IL-4, CXCL10, CXCL8, and CXCL2. Subsequently, serum was collected from other 28 patients with active PMR, 26 patients with PMR in remission, 24 patients with active RA, and 24 healthy medical checkups who were diagnosed and treated at the First Affiliated Hospital of Wannan Medical College from January 2021 to July 2023, and the enzyme-linked immunosorbent assay (ELISA) was used to validate and compare the levels of CXCL10 in each group and analyze the correlation between the levels of serum CXCL10 and the parameters of the clinical activities of PMR. RESULTS: Protein microarray screening revealed significant differences in CXCL10 before and after PMR treatment, and ELISA validation revealed that peripheral serum CXCL10 levels were significantly higher in the PMR-active group than in the remission group (P < 0.001), and also significantly higher than in the RA-active group (P = 0.003) and in the healthy control group (P < 0.001); correlation analysis showed a significant positive correlation between serum CXCL10 levels and serum ferritin in PMR patients (r = 0.450, P = 0.024). In the ROC curve for distinguishing PMR and RA, the area under the curve is 0.741, sensitivity = 0.643, and specificity = 0.792. CONCLUSION: CXCL10 may play a role in the pathogenesis of isolated PMR and its level might contribute to the differential diagnosis of PMR and RA. Key Points • The concentration of CXCL10 was higher in peripheral blood of isolated PMR patients. • CXCL10 is a potential diagnostic biomarker for isolated PMR patients. • The level of CXCL10 might contribute to the differential diagnosis of PMR and RA.