Correlation between ultrasound and anatomical findings in fetuses with lower urinary tract obstruction in the first half of pregnancy

Abstract

Objective The prognosis of fetal lower urinary tract obstruction (LUTO) depends upon renal function and also upon the underlying etiology. Precise identification

Early vesico-amniotic shunting — does it change the prognosis in fetal lower urinary tract obstruction diagnosed in the first trimester?

“…Depending on the cause and degree of urethral obstruction, LUTO may be associated with 45-100% prenatal mortality [3], and even postnatal survivors often develop end-stage chronic renal impairment [4]. Fetal LUTO can be suspected as early as at 11-14 weeks of gestation on the basis of the urinary bladder enlargement, referred to as megacystis, especially when the fetal bladder length exceeds 15 mm [5]. Percutaneous vesico-amniotic shunting with drainage of fetal urine to the amniotic cavity, is the most common intervention in LUTO fetuses [6] The second option is fetal cystoscopy with laser fulguration of PUVs.…”

Congenital urinary tract obstruction: defining markers of developmental kidney injury

“…The predictive value of normal parenchyma (on prenatal ultrasound) in detecting the absence of dysplasia or normal renal function was 56%. Detailed ultrasound examination of the urinary tract, particularly when performed by an experienced operator, yields a higher accuracy of diagnosis of congenital urinary tract obstruction (11). Fetal magnetic resonance imaging can provide a more detailed assessment of the fetal urinary tract (12,13), but predictive values of magnetic resonance imaging for congenital urinary tract obstruction are difficult to ascertain, given the selective use of this method and the small numbers of published cases.…”

Congenital Obstructive Nephropathy: Clinical Perspectives and Animal Models

“…Although PUV is the most common cause of congenital lower urinary tract obstruction postnatally, detailed postmortem analysis of fetuses with megacystis and hyperechogenic kidneys showed that isolated severe lower urinary tract obstruction before 25 weeks' gestation was as likely to be due to urethral atresia or stenosis as PUV (Robyr et al, 2005). Urethral atresia may arise in association with complex collections of other genitourinary and/or gastrointestinal anomalies.…”

“…These include gestational age at diagnosis (Hutton et al, 1994); the volume of amniotic fluid (Oliveira et al, 2000;Sarhan et al, 2008); the presence of megacystis (Oliveira, et al, 2000); the appearance of the renal parenchyma on prenatal ultrasound Robyr, et al, 2005;Sarhan, et al, 2008); fetal urinary sodium, calcium, 2-microglobulin, and other urinary solutes and proteins (Decramer et al, 2008;Morris et al, 2007). Additionally, pilot studies show that urine proteome analysis can identify urodynamically significant UPJ obstruction in infants with hydronephrosis with a sensitivity of 83% and a specificity of 92%, although the test had poor diagnostic accuracy in patients older than 1 year of age (Drube et al, 2010).…”