Chen Xiaoqing, Zhang Yong, Yan Liqun, Xie Yangbin, Li Shujing, Zhuang Yongze, Wang Liping
Fuzong Clinical Medical College of Fujian Medical University, Fuzhou, 350025, China.
Department of Nephrology, The 900th Hospital of Joint Logistics Support Force, 156 West Second Ring Road, Fuzhou, 350025, People's Republic of China.
Clin Exp Nephrol. 2024 May;28(5):409-420. doi: 10.1007/s10157-023-02444-9. Epub 2024 Jan 19.
Idiopathic membranous nephropathy (IMN) is a leading cause of end-stage renal disease (ESRD). The purpose of this study was to evaluate whether urinary albumin-to-creatinine ratio (UACR) diurnal variation rate calculated by spot urinary protein test predicts 1-year nephrotic outcomes as a biomarker of proteinuria severity in patients with IMN.
Patients' baseline demographics, blood and urinary biomarkers, and clinical and pathological characteristics were collected retrospectively. Urine samples were collected at 7:00 (before breakfast) and 19:00 (after dinner) to calculate the UACR diurnal variation rate. A prediction model for no remission (NR) was developed statistically based on differences between prognosis groups. Receiver operating characteristic curve (ROC) analysis was performed to evaluate prediction abilities and determine optimal cut-off points of the model and UACR diurnal variation rate alone.
The formula for calculating the probability of NR was exp(L)/(1 + exp(L)), where the linear predictor L = - 22.038 + 0.134 × Age (years) + 0.457 × 24-h urinary protein + 0.511 × blood urea nitrogen (BUN) + 0.014 × serum uric acid (SUA) + 2.411 if glomerular sclerosis + 0.816 × fasting blood glucose (FBG)-0.039 × UACR diurnal variation rate (%). Optimal cut-off points for NR prediction by the final model and UACR diurnal variation rate alone were 0.331 and 58.5%, respectively. Sensitivity and specificity were 0.889 and 0.859 for the final model, and 0.926 and 0.676 for UACR diurnal variation rate alone.
UACR diurnal variation using spot urinary protein is a simpler way to predict nephrotic outcomes and is a highly sensitive screening tool for identifying patients who should undergo further comprehensive risk assessment.
特发性膜性肾病（IMN）是终末期肾病（ESRD）的主要病因。本研究的目的是评估通过即时尿蛋白检测计算出的尿白蛋白与肌酐比值（UACR）日变化率是否可作为IMN患者蛋白尿严重程度的生物标志物来预测1年肾病结局。
回顾性收集患者的基线人口统计学资料、血液和尿液生物标志物以及临床和病理特征。于7:00（早餐前）和19:00（晚餐后）采集尿液样本以计算UACR日变化率。基于预后组间差异，统计学建立无缓解（NR）的预测模型。进行受试者工作特征曲线（ROC）分析以评估预测能力，并确定模型及单独UACR日变化率的最佳截断点。
计算NR概率的公式为exp(L)/(1 + exp(L))，其中线性预测因子L = -22.038 + 0.134×年龄（岁）+ 0.457×24小时尿蛋白 + 0.511×血尿素氮（BUN）+ 0.014×血清尿酸（SUA）+ 2.411（如果存在肾小球硬化）+ 0.816×空腹血糖（FBG）- 0.039×UACR日变化率（%）。最终模型和单独UACR日变化率预测NR的最佳截断点分别为0.331和58.5%。最终模型的敏感性和特异性分别为0.889和0.859，单独UACR日变化率的敏感性和特异性分别为0.926和0.676。
使用即时尿蛋白检测UACR日变化是预测肾病结局的一种更简单方法，并且是用于识别应接受进一步全面风险评估患者的高灵敏度筛查工具。
