The early diagnostic value of serum neopterin and cartilage oligomeric matrix protein for osteoarticular changes among brucellosis patients at an early period

Background: Brucellosis is an important public health problem in China. Brucellosis can cause many osteoarticular changes, especially chronic brucellosis. Brucellosis presents various diagnostic difficulties because it mimics many other diseases. Because of the poor sensitivity and ability of X-ray image, it is necessary to find a good method of early diagnosis for osteoarticular changes among brucellosis patients at an early period. The aim of this study was to find early changes biomarkers for osteoarticular changes among brucellosis patients at an early period and provide a better understanding of the osteoarticular changes in this disease at an early stage. Methods: Sixty-one cases of brucellosis patients at an early period (within 6 months) and 67 cases of volunteers were selected and divided into brucellosis vs. control groups. Serum samples were detected with serological tests for brucellosis, including rose bengal plate test (RBPT), agglutination test (SAT), and IgG and IgM with ELISA. Meanwhile, cartilage oligomeric matrix protein (COMP) and neopterin (NPT) levels in all samples were measured simultaneously with ELISA. The data were analyzed using SPSS 17.0 software. Results: Together with the clinical examination, epidemiological investigation, and serological tests of RBPT, SAT, and IgG and IgM with ELISA, the patients from brucellosis group all were diagnosed as brucellosis cases at an early period, while the results of RBPT, SAT, and IgG and IgM with ELISA from the healthy control group were negative. Comparing with the healthy control, the medians of serum NPT and COMP in the patients group were 9.26 ng/l, 1.70 ng, respectively, which were higher than that of the healthy control group with significant differences (Z = 5.512, 3.614, all p = 0.000). Conclusion: The serum NPT and COMP levels of brucellosis patients at an early period were increased. The serum NPT and COMP levels might be the indicator biomarker for osteoarticular changes of human brucellosis at an early stage.