Serial Amnioinfusion as Regenerative Therapy for Pulmonary Hypoplasia in Fetuses With Intrauterine Renal Failure or Severe Renal Anomalies: Systematic Review and Future Perspectives

Outcomes of fetal lower urinary tract obstruction based on timing of oligohydramnios onset

OBJECTIVE

Fetal Lower Urinary Tract Obstruction (LUTO) is associated with oligohydramnios and significant fetal morbidity, resulting in poor lung development and perinatal death. However, oligohydramnios may develop at different gestational periods, and the impact of timing on fetal outcomes remains unknown. Our objective was to characterize the impact onset of oligohydramnios had on prenatal outcomes.

METHODS

This study is a retrospective cohort study of all patients with a prenatal diagnosis of LUTO at our tertiary referral center from 2014 to 2023. All patients underwent detailed ultrasonography and interdisciplinary counseling and were subsequently delivered at our institution. Data were obtained from electronic medical records and complete extraction was required for final inclusion.

RESULTS

During the study time period, 93 patients met inclusion criteria of which 68 (73.1%) developed oligohydramnios during their pregnancy. 63 (93%) of these pregnancies resulted in livebirths with 28 (41.1%) perinatal deaths. Onset of oligohydramnios was earlier in pregnancies with perinatal death (23 vs. 28 weeks, p = 0.004) and associated with pulmonary hypoplasia.

CONCLUSIONS

Our data show the impact of oligohydramnios timing in pregnancy on pulmonary hypoplasia and ultimately perinatal death. This allows for detailed patient counseling on the impact oligohydramnios may have on pregnancies by the gestational age of onset.

Ethical Concerns for Amnioinfusions to Treat Early-Onset Anhydramnios

This Viewpoint discusses the long-term medical, emotional, and financial implications of using amnioinfusion to treat anhydramnios; outlines the ongoing Renal Anhydramnios Fetal Therapy (RAFT) trial, which aims to document outcomes and survival in infants after amnioinfusion; and suggests that amnioinfusions be withheld in early anhydramnios, pending the findings of the RAFT trial.

Fetal Therapy for Renal Anhydramnios

The most severe forms of congenital anomalies of the kidney and urinary tract present in fetal life with early pregnancy renal anhydramnios and are considered lethal due to pulmonary hypoplasia without fetal therapy. Due to the high rate of additional structural anomalies, genetic abnormalities, and associated syndromes, detailed anatomic survey and genetic testing are imperative when stratifying which pregnancies are appropriate for fetal intervention. Restoring amniotic fluid around the fetus is the principal goal of prenatal treatment. The ongoing multi-center Renal Anhydramnios Fetal Therapy (RAFT) trial is assessing the safety and efficacy of serial amnioinfusions to prevent pulmonary hypoplasia so that the underlying renal disease can be addressed.

Outcomes of dialysis in neonates with anuric end-stage renal disease at birth: ethical considerations

INTRODUCTION

We present a case series of neonates with anuric ESRD undergoing renal replacement therapy (RRT) and discuss the associated ethical implications of RRT in this population.

METHODS

We reviewed patients who initiated RRT within 1 week of life due to anuric ESRD from 2009-2019 at a single tertiary center. Primary outcomes were receipt of renal transplant (RT), one-year survival, and overall survival.

RESULTS

Five patients met the inclusion criteria. Two patients received an RT. One-year survival was 80%, while overall survival was 60% with a median follow-up of 18 months. In the 2 still-living patients who have not undergone RT, they are ineligible, one due to recent malignancy and the other from acquired cardiovascular comorbidities.

CONCLUSION

Patients with anuric ESRD requiring RRT undergo multiple treatment challenges with low RT and survival rates. These findings should be shared with families considering intervention for cases of severe renal disease diagnosed prenatally.

Selection of candidates for foetal intervention in congenital lower urinary tract obstruction

PURPOSE OF REVIEW

Congenital lower urinary tract obstruction (LUTO) is a rare group of conditions characterized by high perinatal morbidity and mortality if associated with oligohydramnios or anhydramnios in early pregnancy. Although foetal intervention has the potential to improve perinatal survival in a select group of foetuses with LUTO, the actual selection of those candidates most likely to benefit from intervention remains challenging.

RECENT FINDINGS

Foetuses with LUTO who are potential candidates for prenatal intervention should undergo detailed multidisciplinary evaluation to ensure proper assessment and counselling. Using a combination of multiple ultrasound-based renal parameters, including measurement of foetal bladder volumes before and after vesicocentesis and kidney size and morphology, combined with repeated foetal urine biochemistry may allow for better selection than any single test.

SUMMARY

Foetal intervention should be offered to women carrying a foetus with LUTO only after appropriate evaluation and counselling. A combined approach utilizing ultrasound and biochemical measurements of foetal renal function appears best. Research focusing on the development of more accurate markers is needed.