Chevalier Robert L
Department of Pediatrics, University of Virginia, Box 800386, Charlottesville, VA 22908, USA.
Pediatr Radiol. 2008 Jan;38 Suppl 1:S35-40. doi: 10.1007/s00247-007-0585-z. Epub 2007 Dec 11.
Although congenital urinary tract obstruction is a common disorder, its pathophysiology remains poorly understood and clinical practice is controversial. Animal models have been used to elucidate the mechanisms responsible for obstructive nephropathy, and the models reveal that renal growth and function are impaired in proportion to the severity and duration of obstruction. Ureteral obstruction in the neonatal rat or mouse leads to activation of the renin-angiotensin system, renal infiltration by macrophages, and tubular apoptosis. Nephrons are lost by glomerular sclerosis and the formation of atubular glomeruli, and progressive injury leads to tubular atrophy and interstitial fibrosis. Recovery following release of obstruction depends on the timing, severity, and duration of obstruction. Growth factors and cytokines are produced by the hydronephrotic kidney, including MCP-1 and TGF-beta1, which are excreted in urine and can serve as biomarkers of renal injury. Because MRI can be used to monitor renal morphology, blood flow, and filtration rate, its use might supplant current imaging modalities (ultrasonography and diuretic renography), which have significant drawbacks. Combined use of MRI and new urinary biomarkers should improve our understanding of human congenital obstructive nephropathy and should lead to new approaches to evaluation and management of this challenging group of patients.
尽管先天性尿路梗阻是一种常见疾病，但其病理生理学仍未得到充分理解，临床实践也存在争议。动物模型已被用于阐明梗阻性肾病的发病机制，这些模型显示，肾脏的生长和功能损害程度与梗阻的严重程度和持续时间成正比。新生大鼠或小鼠的输尿管梗阻会导致肾素-血管紧张素系统激活、巨噬细胞浸润肾脏以及肾小管凋亡。肾单位因肾小球硬化和无肾小管肾小球的形成而丢失，进行性损伤会导致肾小管萎缩和间质纤维化。解除梗阻后的恢复情况取决于梗阻的时机、严重程度和持续时间。积水性肾病肾脏会产生生长因子和细胞因子，包括MCP-1和TGF-β1，它们会随尿液排出，可作为肾损伤的生物标志物。由于MRI可用于监测肾脏形态、血流和滤过率，其应用可能会取代目前存在显著缺点的成像方式（超声检查和利尿肾图）。MRI与新型尿液生物标志物的联合应用应能增进我们对人类先天性梗阻性肾病的理解，并应能带来评估和管理这类具有挑战性患者群体的新方法。
