Serum complement C1q level in patients with polymyositis/dermatomyositis and its clinical significance
10.3760/cma.j.cn114452-20191031-00622
- VernacularTitle:多发性肌炎与皮肌炎患者血清补体C1q检测的临床意义
- Author:
Lei SHI
1
;
Yiyi WANG
;
Jue ZHANG
Author Information
1. 上海中医药大学附属曙光医院检验科，上海 201203
- From:
Chinese Journal of Laboratory Medicine
2020;43(4):452-456
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the serum complement C1q level in patients with polymyositis/dermatomyositis (PM/DM) and its clinical significance.Methods:Thirty patients with PM/DM admitted to the Department of Endocrinology in Shuguang Hospital from January 2016 to December 2018 were selected as the case group. Thirty healthy people for physical examination in the same period in Shuguang Hospital were selected as the control group. The levels of complement C1q and creatine kinase (CK) in the serum of all the subjects were detected. Meanwhile, the levels of anti-Jo-1 antibody(Jo-1) , antineutrophil cytoplasmic antibodies (ANCA) and anti-ribonuclear protien antibody (RNP) in PM/DM patients were detected. The levels of complement C1q and CK in the serum of PM/DM patients with different clinical symptoms and antibody expression were compared. The working characteristics (ROC curve) were used to determine the diagnostic efficacy of complement C1q and CK for PM/DM.Results:Compared with the control group, the levels of complement C1q [(241.26±26.10) mg/L vs (125.04±11.87)mg/L] and CK[(561.03±29.48)mU/ml vs (161.74±15.86)mU/ml] in serum of patients with PM and DM were higher ( t=22.201, P=0.026; t=65.331, P=0.012) , but there was no significant difference in the levels of complement C1q [(254.63±29.24) mg/L vs (240.18±25.72) mg/L] and CK[(557.19±50.10)mU/ml vs (585.42±63.64)mU/ml] between PM and DM( t=1.427, P=0.165; t=1.358, P=0.185). The serum complement C1q and CK in patients with myalgia, limb muscle weakness, Reynolds phenomenon, arthralgia, Yang rash, interstitial lung disease, Gottron sign, V sign, dysphagia and other organ-accumulated patients were increased( P<0.05). The levels of complement C1q[(189.25±24.20) mg/L vs (352.19±30.22) mg/L; (207.31±16.29)mg/L vs (298.16±34.29) mg/L] and CK[(524.56±51.32) mU/ml vs (752.56±49.61)mU/ml; (497.36±54.28) mU/ml vs (651.22±58.26)mU/ml] in patients with serum of Jo-1 or ANCA positive were lower than those of negative patients (χ 2=8.536, P=0.019;χ 2=7.694, P=0.037 and χ 2=12.696, P=0.027; χ 2=10.763, P=0.046). The levels of complement C1q [(316.00±34.82) mg/L vs (225.46±41.38) mg/L] and CK[(624.18±26.10)mU/ml vs (468.25±24.27)mU/ml] in serum of RNP positive patients were higher than those of negative patients (χ 2=6.712, P=0.041; χ 2=11.751, P=0.038). The ROC curves of complement C1q and CK in diagnosis of PM/DM were 0.842 and 0.783 respectively, and the Jordan index was 0.811 and 0.534 respectively, which had certain value for diagnosis of PM/DM, but that of the complement C1q level was higher than that of CK ( P<0.05). The sensitivity and specificity of complement C1q were 88.95% and 92.10% respectively with 231.820 mg/L as the critical value, which was higher than that of CK (68.42% and 85.00%)( P<0.05). Conclusions:The expression of complement C1q in serum of PM/DM patients is increased, which is related to the clinical symptoms and antibody levels of PM/DM patients. It may be involved in the progression of PM/DM disease.
