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

Abstract

Objectives: The aim of the study was to assess the outcome of vesico-amniotic shunting performed before 16 weeks of pregnancy in fetuses with severe megacystis diagnosed in the first trimester of pregnancy. Material and methods:Between January 2008 and October 2012 severe megacystis with the bladder length > 15 mm was diagnosed in 17 fetuses. The procedure of early vesico-amniotic shunting (VAS) was offered to 8 patients with presumably isolated LUTO.The procedure of VAS was performed in 6 fetuses. Before the intervention one or two procedures of vesicocentesis and urine analysis were performed. Results:In all treated cases shunts provided urinary tract decompression. All babies were born prematurely, 2 of them died due to premaurity, 3 of them survived and have normal renal function at the age of 5-6 years. In 4/5 children accompanying malformations were later diagnosed, in 1 born prematurely neonate necropsy was not performed. Conclusions:Our results suggest that early vesico-amniotic shunting in fetal LUTO is feasible and may potentially prevent not only pulmonary hypoplasia but also renal insufficiency. However, the rationale of the procedure needs further investigation due to a high risk of long-term morbidity and co-existing malformations in children Before offering the therapy detailed counseling of the parents about the possible pros and cons of the therapy is necessary.

Antenatal Workup of Early Megacystis and Selection of Candidates for Fetal Therapy

“…Animal studies have demonstrated a correlation between early LUTO and severity of renal damage, thus suggesting that an early treatment, although technically more challenging, may potentially improve the outcome [19,20]. New therapeutic attempts, based on recent technical improvements, aim at sparing renal function starting from 14-16 weeks' gestation [3][4][5]. In this context, it has become extremely important to be able to select, as early as possible, fetuses eligible for timely treatment, should the parents choose for this option.…”

“…Nowadays, thanks to technical improvements, early fetal therapy has however become plausible [3][4][5], as it appears that an early intervention is the only strategy potentially capable of preventing the occurrence of renal damage in the very few cases with truly isolated posterior urethral valves (PUV) [3,6,7]. In the attempt to identify these rare cases -should parents not consider termination of pregnancy as an option -the challenge remains which criteria should be used to effectively detect first-trimester fetuses with complex megacystis and very poor prognosis, on the one hand, and those with a high chance of spontaneous resolution and favorable prognosis, on the other.…”

Urethroplasty with balloon catheterization in fetal lower urinary tract obstruction: observational study of 10 fetuses

“…Prenatal treatment, offered in cases of fetuses with presumed PUVs without underlying genetic defects or additional anatomical anomalies, 6,7 includes vesicoamniotic shunting (VAS) and fetoscopic transvesical laser ablation of posterior urethral valves. [8][9][10][11][12] All above mentioned procedures have some disadvantages and the optimal method of treatment of fetal LUTO has not been developed yet. VAS is associated with many complications including difficulties in placement of the shunt, its obstruction or translocation; additionally, presence of a shunt impairs bladder function resulting in its spasticity and secondary vesicoureteral reflux and hydronephrosis.…”

“…VAS is associated with many complications including difficulties in placement of the shunt, its obstruction or translocation; additionally, presence of a shunt impairs bladder function resulting in its spasticity and secondary vesicoureteral reflux and hydronephrosis. 9,10,[14][15][16][17] An alternative option to VAS is fetal cystoscopy which is much less frequently performed and much more challenging because it requires access with fetoscope to the posterior urethra and identification of the obstruction. Reaching the urethral valves is difficult because of the sharp vesicourethral angle and creates a risk of consequent laserrelated thermal injury of surrounding tissues and even urethrocutaneous or urethrorectal fistulas formation.…”

“…Prenatal management options include expectant management, intrauterine therapeutic intervention and pregnancy termination. Prenatal treatment, offered to cases with presumed PUVs without an underlying genetic defect or additional anatomical anomaly 6,7 , includes vesicoamniotic shunting (VAS) and fetoscopic transvesical laser ablation of the PUVs [8][9][10][11] . However, these procedures have disadvantages and the optimal method for the treatment of fetal LUTO has not been developed yet.…”