Consensus on the prenatal management of antenatally detected urological abnormalities

Timing of delivery in antenatal fetal hydronephrosis: a snap shot social media survery of obstetric and fetal medicine practice

OBJECTIVES

To identify when obstetricians would deliver a fetus with antenatal hydronephrosis and normal liquor. Designed as snap-shot survey. Setting: Survey Monkey link. Population/sample were obstetrics and fetal medicine consultants who received the survey link via closed professional forums on the North West Coast Maternity Clinical Network, Facebook, and publicly on Twitter.

METHODS

Survey link publicised as above, obstetric consultants were asked at what gestation would they deliver a fetus with antenatal hydronephrosis and normal liquor; and what criteria would they use to make that decision. Main outcome measures were number of years in practice, gestation at delivery, anteroposterior diameter (APD) of renal pelvis.

RESULTS

A total of 44/102 respondents (43%) would deliver prior to 40 weeks (median no. of years as consultant 10 years [IQR 5-17]) vs. those who would not (median years as consultant 5.5 [IQR 3-12]). Re APD threshold of delivery: 17 indicated delivery if the APD were 20 mm, 10 if it were 21-30 mm and 16 if it were >30 mm. Re gestation at which they would deliver: 13 indicated 37-38 weeks, 13 indicated 38-39 weeks and 17 indicated 39-40 weeks. Reasons selected for delivery before term were obstetric anxiety n=2, maternal request n=2, maternal anxiety n=2 and concern about fatal renal damage/renal damage n=34.

CONCLUSIONS

A surprising number of respondents would consider early delivery of a fetus with hydronephrosis and normal liquor despite the lack of evidence of benefit. The evidence supporting term delivery means that early term delivery is only indicated for obstetric reasons in this scenario.

Current perspective and scope of fetal therapy: part 1

Fetal therapy term has been described for any therapeutic intervention either invasive or noninvasive for the purpose of correcting or treating any fetal malformation or condition. Fetal therapy is a rapidly evolving specialty and has gained pace in last two decades and now fetal intervention is being tried in many malformations with rate of success varying with the type of different fetal conditions. The advances in imaging techniques have allowed fetal medicine persons to make earlier and accurate diagnosis of numerous fetal anomalies. Still many fetal anomalies are managed postnatally because the fetal outcomes have not changed significantly with the use of fetal therapy and this approach avoids unnecessary maternal risk secondary to inutero intervention. The short-term maternal risk associated with fetal surgery includes preterm labor, premature rupture of membranes, uterine wall bleeding, chorioamniotic separation, placental abruption, chorioamnionitis, and anesthesia risk. Whereas, maternal long-term complications include risk of infertility, uterine rupture, and need for cesarean section in future pregnancies. The decision for invasive fetal therapy should be taken after discussion with parents about the various aspects like postnatal fetal outcome without fetal intervention, possible outcome if the fetal intervention is done, available postnatal intervention for the fetal condition, and possible short-term and long-term maternal complications. The center where fetal intervention is done should have facility of multi-disciplinary team to manage both maternal and fetal complications. The major issues in the development of fetal surgery include selection of patient for intervention, crafting effective fetal surgical skills, requirement of regular fetal and uterine monitoring, effective tocolysis, and minimizing fetal and maternal fetal risks. This review will cover the surgical or invasive aspect of fetal therapy with available evidence and will highlight the progress made in the management of fetal malformations in last two decades.

Quantitative analysis of renal vascularization in fetuses with urinary tract obstruction by three-dimensional power-Doppler

OBJECTIVE

To evaluate the applicability of 3-dimensional evaluation of renal vascularization for predicting postnatal renal function in fetuses with suspected urinary obstruction.

STUDY DESIGN

Fetuses were evaluated by 3-dimensional power-Doppler histogram, and vascular indices were estimated. Depth between the probe and the renal cortex was also evaluated. Postnatal follow-up was obtained in all cases and the main outcome was renal impairment.

RESULTS

Twenty-three fetuses with urinary dilatation (cases) and 73 with normal renal morphology (controls) were included in the current study. Five (21.7%) cases developed renal impairment. Vascularization index and vascularization and flow index were significantly lower in fetuses that developed renal impairment compared with those with normal renal function (P = .009 and P = .036, respectively). The 3 vascular indexes correlated with depth. Percentage of depth-corrected vascularization index and vascularization flow index were lower in fetuses developing postnatal renal failure.

CONCLUSION

Fetal renal vascularity (vascularization index and vascularization and flow index) was significantly lower in fetuses that developed renal impairment.

Ultrasound evaluation of prognosis in fetuses with posterior urethral valves

PURPOSE

The aim of this study was to evaluate the ability of prenatal ultrasound markers to predict postnatal renal prognosis in fetuses with posterior urethral valves.

METHODS

Medical files on fetuses with prenatal diagnosis of posterior urethral valves from 2000 to 2006 were reviewed retrospectively. Data from prenatal follow-up included gestational age at diagnosis, ultrasound renal parenchyma evaluation, and presence and time of oligohydramnios onset. Prenatal parameters studied were correlated to postnatal renal function.

RESULTS

Thirty-one male fetuses were included. Six pregnancies were terminated. Of the remaining 25 pregnancies that were continued, 4 children had abnormal creatine and 21 normal creatinine levels at follow-up. Presence and time of oligohydramnios onset did not differ between groups (P = .43). Ultrasound detected bilateral renal abnormalities in 3 fetuses (75%) with altered renal function, and 10 fetuses (55%) with normal creatinine, at follow-up.

CONCLUSIONS

None of the ultrasound parameters evaluated were able to reliably predict postnatal renal function.