血清中IgA/C3比值在IgA肾病诊断预测中的价值及其与IgA肾病临床及病理联系

目的探讨血清IgA/C3水平在IgA肾病诊断预测中的价值，及其与IgA肾病临床、病理之间的关系。方法收集自2009年
11月~2015年2月于南方医科大学第三附属医院肾活检诊断的66例IgA肾病，111例其他肾小球疾病，40例无肾脏病的健康体
检者。使用CRM470调整后的标准化免疫比浊法检测患者血清中IgA、C3，并计算IgA/C3比值。参照牛津分级及Lee氏分级分
别对IgA肾病患者进行病理学分级。在比较血清IgA、IgA/C3比值在预测IgA肾病的价值时，通过绘制ROC曲线，并计算曲线
下面积。结果IgA肾病患者血清IgA/C3比值较其他肾小球疾病组和健康对照组明显升高，其ROC曲线下面积为0.776。血清
IgA/C3比值升高与IgA肾病病理损伤程度无明显相关性。结论在未开展肾活检的医院及不接受行肾活检的患者，血清IgA/
C3比值在IgA肾病诊断中可起一定辅助作用。

Value of serum IgA/C3 ratio in the diagnosis of IgA nephropathy and its correlation withthe clinicopathological features

Objective To investigate the value of serum IgA/C3 ratio in the diagnosis of IgA nephropathy and explore its
relationship with the clinicopathological features of the patients. Methods Sixty-six patients with IgA nephropathy, 111 with
other glomerular diseases, and 40 healthy control subjects without kidney disease were tested for serum IgA and C3 levels
using CRM470 adjusted standardized immune turbidimetric method, and the IgA/C3 ratio was calculated. According to
Oxford and Lee’s classification criteria, we analyzed the pathological grades of the renal biopsy samples from patients with
IgA nephropathy. The ROC curve was used to assess the value of serum IgA and IgA/C3 ratio in predicting IgA nephropathy.
Results Patients with IgA nephropathy had an elevated serum IgA/C3 ratio than those with other glomerular diseases and the
control subjects, with an area under the ROC curve of 0.776. An elevated serum IgA/C3 ratio was not found to significantly
correlate with the pathological grade of renal biopsy samples in patients with IgA nephropathy. Conclusion In the absence of
renal biopsy findings, serum IgA/C3 ratio can help in the diagnosis of IgA nephropathy.