目的 探讨外周血TGF-β1 及IL-18 mRNA 表达水平在儿童原发性肾病综合征（PNS）的临床诊断分型及病情评估中的作用。方法 采用实时聚合酶链反应(RT-PCR) 技术，对77 例PNS 患儿及30 例健康对照儿童外周血单个核细胞(PBMC) 中TGF-β1 和IL-18 mRNA 表达水平进行检测。结果 激素敏感型肾病综合征（SSNS）患儿中，在激素治疗0（治疗前）、1、4 周时，单纯型肾病患儿血PBMC 中TGF-β1 及IL-18 mRNA 的水平低于肾炎型肾病患儿，差异有统计学意义（P 均<0.05）。在激素治疗0 周时，SSNS 患儿TGF-β1 mRNA 的水平低于激素耐药型肾病综合征（SRNS）患儿，差异有统计学意义（P<0.05）。随着激素治疗时间的延长，各组患儿TGF-β1 mRNA 的水平均呈逐渐下降趋势。SRNS 患儿中，在激素治疗0、1 周时，单纯型肾病患儿血PBMC 中IL-18 mRNA 的表达水平低于肾炎型肾病患儿，差异有统计学意义（P<0.05）。SSNS 患儿中，活动期组TGF-β1 及IL-18 mRNA 水平均高于缓解组，差异有统计学意义(P<0.01)。结论 PNS 疾病初期，检测患儿血清PBMC 中TGF-β1、IL-18 mRNA 表达水平，对评估患儿疾病的活动情况、临床鉴别单纯型肾病与肾炎型肾病及临床早期预测激素耐药有一定意义。

Objective To study the clinical significance of transforming growth factor (TGF)-β1 and interleukin (IL)-18 mRNA in the diagnosis and evaluation of disease severity of primary nephrotic syndrome (PNS) in children. Methods The expression levels of TGF-β1 and IL-18 mRNA in peripheral blood mononuclear cells (PBMC) were measured by real-time fluorescent quantitative polymerase reaction (RT-PCR) in 77 children with PNS and 30 healthy children (control group). Results In children with steroid-sensitive nephrotic syndrome (SSNS), the expression levels of TGF-β1 and IL-18 mRNA before treatment and at 1, 4 weeks after hormone therapy were significantly lower in children with simple type nephrotic syndrome than those in children with nephritic type nephrotic syndrome (P<0.05). The level of TGF-β1 mRNA before treatment was significantly lower in children with SSNS than that in children with steroid-resistant nephrotic syndrome (SRNS). With the extension of hormone therapy, the expression levels of TGF-β1 mRNA showed a trend of declining in children with PNA. In children with SRNS, the expression levels of TGF-β1 and IL-18 mRNA before treatment and at 1, 4 weeks after hormone therapy were significantly lower in children with simple type NS than those in children with nephritic type nephrotic syndrome (P<0.05). In children with SSNS, the levels of TGF-β1 and IL-18 mRNA were significantly higher in acute phase than those in the remission phase. Conclusions At the early stage of PNS, the detection of the expression levels of TGF-β1 and IL-18 mRNA is useful for evaluatation of disease activity, clinical identification of nephritic type nephrotic syndrome and simple type nephrotic syndrome and early prediction of SRNS.