Department of Urology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
Department of Urology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
J Pediatr Urol. 2019 Dec;15(6):605.e1-605.e8. doi: 10.1016/j.jpurol.2019.08.015. Epub 2019 Aug 27.
To investigate the postoperative long-term prognosis and the factors predicting the renal function of patients with reflux nephropathy. As the serum creatinine (s-Cr) level tends to increase during infancy, the degree of reflux and renal parenchymal damage are thought to be more important factors in pediatric patients than in older patients.
This study examined s-Cr, urinary protein, and blood pressure of patients who underwent anti-reflux surgery 10 years before. It also calculated the postoperative estimated glomerular filtration rate (eGFR) and examined the correlation between the eGFR and preoperative factors (age, gender, number of urinary tract infections [UTIs], primary diagnosis, reflux grade, percentage of dimercaptosuccinic acid uptake, degree of renal parenchymal damage, s-Cr abnormality, proteinuria, and hypertension), and analyzed the factors associated with the long-term prognosis.
The study population was 51 infants (37 boys and 14 girls). The mean age of the patients before surgery and at the follow-up examination was 3.41 ± 3.61 and 14.63 ± 3.74 years, respectively. After surgery, the s-Cr, urinary protein, and blood pressure values showed (44.7%, 26.7%, and 18.2%, respectively) were abnormal. The postoperative eGFR was a mean 90.27 ± 20.42 ml/min/1.73 m and primary correlated with an older age (P = 0.0361), no UTI at the primary diagnosis (P = 0.0044), reflux grade ≥8 (P = 0.0180), degree of renal parenchymal damage (group ≥2b, P < 0.0001), s-Cr abnormality (P < 0.0001), and proteinuria (P = 0.0001) at baseline. A total of 20 patients had chronic kidney disease (CKD; Fig. 1). The multiple regression analysis of these factors revealed that an older age (P = 0.0021), reflux grade ≥8 (P = 0.0134), and degree of renal parenchymal damage (group ≥2b, P < 0.0001) were significantly associated with the long-term postoperative prognosis of reflux nephropathy. Using these three factors, this study derived a multiple regression equation estimating eGFR in the 10th year after surgery (Fig. 1).
In this study, severe vesico-ureteral reflux (reflux grade ≥8) and severe renal parenchymal damage (group ≥2b) were associated with a long-term decrease in the eGFR. In particular, renal parenchymal damage was closely correlated with the postoperative eGFR; thus, this was clearly a critical factor. The age at surgery showed a better correlation with the postoperative eGFR in the multiple regression analysis; thus, age was regarded as an independent prognostic factor.
The age, reflux grade, and degree of renal parenchymal damage at baseline were factors that affected the long-term postoperative prognosis of reflux nephropathy. Patients with high-grade reflux and severe renal parenchymal damage were more likely to show a reduced CKD level at 10 years after anti-reflux surgery.
探讨反流性肾病患者的术后长期预后及预测肾功能的因素。由于婴儿期血清肌酐（s-Cr）水平趋于升高，反流程度和肾实质损伤被认为在儿科患者中比在老年患者中更为重要。
本研究检查了 10 年前接受抗反流手术的患者的 s-Cr、尿蛋白和血压。还计算了术后估计肾小球滤过率（eGFR），并检查了 eGFR 与术前因素（年龄、性别、尿路感染次数[UTI]、原发性诊断、反流分级、二巯丁二酸摄取百分比、肾实质损伤程度、s-Cr 异常、蛋白尿和高血压）之间的相关性，并分析了与长期预后相关的因素。
研究人群为 51 名婴儿（37 名男孩和 14 名女孩）。手术前和随访检查时患者的平均年龄分别为 3.41±3.61 岁和 14.63±3.74 岁。手术后，s-Cr、尿蛋白和血压值分别为（44.7%、26.7%和 18.2%）异常。术后 eGFR 平均为 90.27±20.42ml/min/1.73m，主要与年龄较大（P=0.0361）、原发性诊断无 UTI（P=0.0044）、反流分级≥8（P=0.0180）、肾实质损伤程度（组≥2b，P<0.0001）、s-Cr 异常（P<0.0001）和蛋白尿（P=0.0001）相关。共有 20 名患者患有慢性肾脏病（CKD；图 1）。对这些因素进行多元回归分析显示，年龄较大（P=0.0021）、反流分级≥8（P=0.0134）和肾实质损伤程度（组≥2b，P<0.0001）与反流性肾病的长期术后预后显著相关。使用这三个因素，本研究得出了一个估计术后第 10 年 eGFR 的多元回归方程（图 1）。
在这项研究中，严重的膀胱输尿管反流（反流分级≥8）和严重的肾实质损伤（组≥2b）与 eGFR 的长期下降有关。特别是，肾实质损伤与术后 eGFR 密切相关，因此这显然是一个关键因素。在多元回归分析中，手术时的年龄与术后 eGFR 的相关性更好；因此，年龄被视为一个独立的预后因素。
基线时的年龄、反流分级和肾实质损伤程度是影响反流性肾病术后长期预后的因素。患有高等级反流和严重肾实质损伤的患者在抗反流手术后 10 年更可能出现较低的 CKD 水平。
