摘要目的:了解原发性IgA肾病(IgAN)患儿血清补体因子B(CFB)水平，探讨该补体水平与IgAN的临床表现和预后的相关性。方法:收集2014年12月至2017年4月在郑州大学第一附属医院肾脏内科住院经肾穿刺活检确诊为原发性IgAN的患儿204例[年龄(11.0±3.5)岁]为IgAN组。选取同期在郑州大学第一附属医院健康体检儿童84例[年龄(10.9±3.2)岁]为健康对照组。应用酶联免疫吸附法检测各组血清CFB水平，根据IgAN组患儿血清CFB中位数水平将该组分为高CFB组(102例)和低CFB组(102例)。采用 Spearman相关分析各指标间的相关性、多因素 Cox比例风险回归模型分析血清CFB水平与儿童IgAN肾脏预后的关系。 结果:IgAN组患儿血清CFB水平高于健康对照组[290.9(186.2~453.9) mg/L比218.9(155.0~321.3) mg/L， Z＝-3.372， P＝0.001]。IgAN组患儿血清CFB与血清白蛋白( r＝-0.388， P<0.001)、估算肾小球滤过率( r＝-0.416， P<0.001)呈负相关，与血清肌酐( r＝0.305， P<0.001)、24 h尿蛋白定量( r＝0.456， P<0.001)呈正相关。IgAN患儿高CFB组有新月体(C1-2)的比例(70.6%比29.4%， χ2＝34.588， P<0.001)及C 3沉积较强(++~+++)的比例(63.7%比44.1%， χ2＝7.892， P＝0.005)均高于低CFB组。 Kaplan- Meier生存曲线分析显示IgAN患儿高CFB组肾脏累积生存率低于低CFB组( χ2＝17.509， P<0.001)。多因素 Cox回归分析显示，高CFB水平与儿童IgAN肾脏不良预后相关( HR＝2.517，95% CI：1.284~4.932， P＝0.007)。 结论:高血清CFB水平与IgAN患儿肾功能下降、尿蛋白排泄增加、新月体形成及肾脏不良预后相关。

abstractsObjective:To detect serum level of complement factor B (CFB), and to explore its correlations with clinical parameters and prognosis in children with primary IgA nephropathy (IgAN).Methods:A total of 204 children with primary IgAN confirmed by kidney biopsy in the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University from December 2014 to April 2017 were included in IgAN group.During the same period, 84 healthy children were included in healthy control group.Their mean age was (11.0±3.5) years and (10.9±3.2) years, respectively.Patients in IgAN group were divided into low CFB group (102 cases) and high CFB group (102 cases) according to the medium serum level of CFB measured by enzyme-linked immunosorbent assay. Spearman′ s coefficient was employed to analyze correlation amongst various parameters.Multivariable-adjusted Cox proportional ha-zards models were used to evaluate the relationship between serum CFB level and prognosis in children with IgAN. Results:Serum CFB levels were significantly higher in IgAN group than that in healthy control group [290.9 (186.2-453.9) mg/L vs.218.9 (155.0-321.3) mg/L, Z=-3.372, P=0.001]. Serum levels of CFB were negatively correlated with serum albumin ( r=-0.388, P<0.001) and estimated glomerular filtration rate ( r=-0.416, P<0.001), but positively correlated with serum creatinine ( r=0.305, P<0.001) and 24 h urinary protein ( r=0.456, P<0.001) in IgAN group.The incidences of crescents (C1-2) (70.6% vs.29.4%, χ2=34.588, P<0.001) and C 3 deposition (+ + -+ + + ) (63.7% vs.44.1%, χ2=7.892, P=0.005) were significantly higher in high CFB group than those in low CFB group. Kaplan- Meier analysis showed that high CFB levels predicted worse renal outcome in pediatric IgAN patients ( χ2=17.509, P<0.001). Multivariate Cox regression analysis showed that the high CFB level was the independent risk factor for the poor renal outcome ( HR=2.517, 95% CI: 1.284-4.932, P=0.007). Conclusions:High serum levels of CFB are associated with decreased renal function, increased urinary protein excretion, crescentic formation and poor renal outcome in pediatric IgAN patients.