Investigation on the serum marker of MPO-ANCA associated vasculitis in active phase / 医学研究生学报

ABSTRACT

Objective Antineutrophil cytoplasmic antibody (ANCA) associated vasculitis(AAV)is a systemic necrotizing small-vessel vasculitis, and myeloperoxidase(MPO) is one of the main antigens that ANCA can recognize.This study was to investigate the clinical significance of MPO, activated complement C5a fragment and ceruloplasmin ( Cp) in the peripheral blood of patients with MPO-ANCA associated vasculitis ( MPO-AAV) in active phase by observing their changes. Methods 132 MPO-AAV patients at active stage were selected as the patient group, while the control group was made up of 30 healthy controls.Peri-nuclear ANCA (p-ANCA) and MPO-ANCA in the patient group were detected by IIF and ELISA, respectively.The levels of MPO, Cp and C5a in both groups were tested by ELISA.The Birmingham vasculitis activity score (BVAS) of every patient was calculated.In the patient group, the relationship among MPO, Cp, C5a and MPO-ANCA were analysed, and the association between BVAS and each of them was also explored. Results The levels of MPO, CP, C5a in the patient group were significantly higher than those in the health control group [MPO:400.7(333.5~506.1) vs 286.9(225.5~329.1)IU/L, P<0.001;C5a:336.7 (277.6~403.5) vs 236.8 (204.2~304.1) ng/mL, P<0.001;Cp:481.1 (387.9~535.9) vs 326.9 (177.1~405.5) ng/mL,P<0.001].The associations between MPO and Cp, C5a and MPO, C5a and Cp in the patient group were statistically significant ( r=0.663, P<0.001;r=0.792, P<0.001;r=0.637, P<0.001, respectively).No significant correlation was found in MPO-ANCA and any of these indexes.MPO-ANCA had a positive association with the total BVAS, the kidney BVAS, and the lung BVAS ( r=0.247, P=0.004;r=0.339,P<0.001 and r=0.191, P=0.028, respec-tively) .p-ANCA had a positive correlation with the kidney BVAS ( r=0.208, P=0.017) while C5a had a negative correlation with the kidney BVAS ( r=-0.207, P=0.018) . Conclusion The levels of MPO, Cp and C5a increased significantly in the peripheral blood of MPO-AAV patients in active phase.The complex interactions among MPO, Cp, C5a and ANCA might influence the clinical damage in MPO-AAV.Notablely, the influence from MPO-ANCA might be most obvious while C5a might affect renal damage more markedly.