Has Recep, Sarac Sivrikoz Tugba
Division of Perinatology, Department of Obstetrics and Gynecology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Front Pediatr. 2020 Sep 4;8:492. doi: 10.3389/fped.2020.00492. eCollection 2020.
The widespread use of obstetric ultrasonography has increased the detection rate of antenatal hydronephrosis. Although most cases of antenatal hydronephrosis are transient, one third persists and becomes clinically important. Ultrasound has made differential diagnosis possible to some extent. Ureteropelvic junction type hydronephrosis (UPJHN) is one of the most common cause of persistent fetal hydronephrosis and occurs three times more in male fetuses. It is usually sporadic and unilateral. However, when bilateral kidneys are involved and presents with severe hydronephrosis, the prognosis may be poor. Typical ultrasound findings of UPJHN is hydronephrosis without hydroureter. The size and appearance of the fetal bladder is usually normal without thickening of the bladder wall. Several grading systems are developed and increasingly being used to define the severity of prenatal hydronephrosis and provides much more information about prediction of postnatal renal prognosis. If fetal urinary tract dilation is detected; laterality, severity of hydronephrosis, echogenicity of the kidneys, presence of ureter dilation should be assessed. Bladder volume and emptying, sex of the fetus, amniotic fluid volume, and presence of associated malformations should be evaluated. Particularly the ultrasonographic signs of renal dysplasia, such as increased renal parenchymal echogenicity, thinning of the renal cortex, the presence of cortical cysts, and co-existing oligohydramnios should be noticed. Unfortunately, there is no reliable predictor of renal function in UPJHN cases. Unilateral hydronephrosis cases suggesting UPJHN are mostly followed up conservatively. However, the cases with bilateral involvement are still difficult to manage. Timing of delivery is also controversial.
产科超声检查的广泛应用提高了产前肾积水的检出率。虽然大多数产前肾积水病例是暂时的，但三分之一会持续存在并具有临床意义。超声在一定程度上使鉴别诊断成为可能。肾盂输尿管连接部型肾积水（UPJHN）是持续性胎儿肾积水最常见的原因之一，在男性胎儿中发生率高出三倍。它通常是散发性的且为单侧性。然而，当双侧肾脏受累并出现严重肾积水时，预后可能较差。UPJHN的典型超声表现是肾积水而无输尿管积水。胎儿膀胱的大小和外观通常正常，膀胱壁无增厚。已开发出几种分级系统，并越来越多地用于定义产前肾积水的严重程度，且能提供更多关于产后肾脏预后预测的信息。如果检测到胎儿尿路扩张，应评估其侧别、肾积水的严重程度、肾脏的回声、输尿管扩张的情况。还应评估膀胱容量和排空情况、胎儿性别、羊水量以及是否存在相关畸形。尤其应注意肾发育不良的超声征象，如肾实质回声增强、肾皮质变薄、皮质囊肿的存在以及并存羊水过少的情况。不幸的是，在UPJHN病例中没有可靠的肾功能预测指标。提示UPJHN的单侧肾积水病例大多采取保守随访。然而，双侧受累的病例仍然难以处理。分娩时机也存在争议。
