Diagnóstico prenatal de anomalías nefrourológicas en el Centro de Referencia Perinatal Oriente, Santiago, Chile / Prenatal diagnosis of nefrourological anomalies at the Eastern Perinatal Referral Center, Santiago, Chile

INTRODUCCIÓN: Las anomalías congénitas de los riñones y las vías urinarias (CAKUT, Congenital Anomalies of the Kidney and Urinary Tract) representan un 20-30% de las anomalías detectadas en el periodo prenatal. Si bien la mayoría son de buen pronóstico, un 25% se asocian a enfermedad renal crónica en la infancia y en los casos graves a mortalidad perinatal. OBJETIVO: Describir los casos ingresados al Centro de Referencia Perinatal Oriente (CERPO) y determinar los resultados perinatales y la sobrevida al año. MÉTODO: Estudio descriptivo y retrospectivo. Se incluyeron pacientes ingresadas en la base de datos CERPO, entre los años 2003 y 2019, con diagnóstico de anomalía nefrourológica. Se incluyeron antecedentes prenatales, perinatales y de seguimiento posnatal al año. RESULTADOS: Se evaluaron 273 pacientes. La edad gestacional promedio de derivación fue de 29 semanas + 2 días. El diagnóstico más frecuente fueron las anomalías del tracto de salida (69%). Un 40% de los casos se asociaron a otras anomalías congénitas, siendo las cardiopatías las más frecuentes (19%). Aceptaron la realización de estudio genético invasivo 38 pacientes, de las cuales un 34% presentaron aneuploidías, siendo las trisomías 18 y 13 las más frecuentes (17% y 6%, respectivamente). Se instalaron cinco shunts derivativos vesicoamnióticos en fetos diagnosticados con megavejiga. La sobrevida global para la patología nefrourológica fue del 63% al año, y la mortalidad fetal y neonatal fue del 7% y el 16%, respectivamente. La sobrevida al año según el grupo de clasificación CAKUT fue del 22% para las anomalías de número de riñones, del 46% para las anomalías de tamaño y de morfología renal, del 60% para las anomalías de la posición renal y del 72% para las anomalías del tracto de salida. En este último grupo, la sobrevida alcanza el 81% al excluir los pacientes con diagnóstico prenatal de megavejiga, que presentaron una sobrevida al año del 28%. Los casos de patología nefrourológica asociada a oligohidramnios (índice de líquido amniótico < 5 cm) sin evidencias de uropatía obstructiva asociada presentaron una sobrevida al año del 3%. CONCLUSIONES: Las anomalías del sistema nefrourológico son un diagnóstico prenatal frecuente. La sobrevida al año fue del 63%, pero es necesario prolongar el seguimiento a largo plazo para determinar la evolución de la función renal en cada diagnóstico. La asociación de patología nefrourológica y oligohidramnios conlleva una sobrevida menor.

INTRODUCTION: Congenital anomalies of the kidneys and urinary tract (CAKUT) represent 20 to 30% of the anomalies detected prenatally. Although most are of good prognosis, 25% are associated with chronic kidney disease in childhood and severe cases with perinatal mortality. OBJECTIVE: To describe the cases studied in the Eastern Perinatal Referral Center (CERPO) and to determine the perinatal outcome and survival at one year. METHOD: Descriptive and retrospective study. Patients registered on the CERPO database, between 2003 to 2019, with diagnosis of nephrourological anomaly were included. Antenatal, perinatal and postnatal follow-up information was collected. RESULTS: 273 patients were evaluated. The average gestational age at referral was 29 + 2 weeks. The main diagnosis was urinary tract outlet disorders (69%). Thirty nine percent of the cases were associated with other congenital anomalies, with heart disease being the most frequent (19%). Thirty-eight patients accepted an invasive procedure for genetic study, 34% presented aneuploidy, trisomy 18 and 13 were the most frequent (17% and 6% respectively). Five vesico-amniotic derivative shunts were installed in fetuses diagnosed with megabladder. Overall survival at one year was 63% and fetal and neonatal mortality were 7% and 16% respectively. One-year survival per group according to CAKUT classification was 22% in kidney number abnormalities, 46% in kidney size and morphology abnormalities, 60% in renal position abnormalities and 72% in outflow tract abnormalities. In the latter, survival reaches 81% excluding the patients with prenatal diagnosis of megabladder who had a one-year survival of 28%. The cases of nephrourological pathology associated with oligohydramnios (amniotic fluid index < 5 cm) without evidence of associated obstructive uropathy presented a survival of 3% at one year. CONCLUSIONS: The anomalies of the nephrourological system correspond to a frequent prenatal diagnosis. Overall, the one-year survival was 63%; however, follow-up must continue to determine the evolution of renal function in relation to each diagnosis.

Variación de la microglobulina beta-2 en orina fetal en punciones sucesivas previo a derivación vesicoamniótica antenatal

Introduction. Fetal obstructive uropathy can be treated early in pregnancy by intrauterine vesicoamniotic shunting, immediately after diagnosis by ultrasound, in specific cases with a favorable prognosis in renal function using fetal urine beta2 microglobulin. Objective: To determine the changes of beta-2 microglobulin in consecutive samples of fetal urine in 48 - 72 hour-intervals in fetuses with obstructive uropathy at 16 weeks of gestation. Methods: We designed a descriptive and longitudinal study, including 15 pregnant women whose fetuses were diagnosed with obstructive uropathy without chromosomal abnormalities, performing vesicocentesis for urinary biometry. Results: Beta-2 microglobulin values were higher than 4 mg/dL in the first vesicocentesis of all 15 cases and decreased to less than 4 mg/dL in 7 cases (46.6%) after the second vesicocentesis. In all cases when beta-2 microglobulin was less than 8 mg/dL in the first vesicocentesis, there was a decrease to nearly 4 mg/dL (maximum 4.3 mg/dL) in the second vesicocentesis. Conclusions: Vesicoamniotic shunting should be performed in all cases of fetal obstructive uropathy when the values of beta-2 microglobulin are less than 8 mg/dL in the first vesicocentesis.

Antecedentes y objetivos. La uropatía obstructiva fetal puede ser tratada precozmente mediante la colocación de derivación vesicoamniótica intrauterina. Los criterios de tratamiento incluyen la ausencia de malformaciones mayores asociadas, cariotipo normal y función renal conservada demostrada por microglobulina beta-2 4 mg/dL en los 15 casos con la primera vesicocentesis, y disminuyeron a < 4 mg/dL en 7 casos (46,6%) en la segunda vesicocentesis. En todos los casos cuando la microglobulina beta-2 fue < 8 mg/dL en la primera vesicopunción, siempre disminuyó a valores muy próximos a 4 mg/dL (máximo de 4,3 mg/dL) en la segunda vesicopunción. Conclusiones. Se plantea la colocación in útero de derivaciones vesicoamnióticas en los casos de uropatía obstructiva fetal cuando la microglobulina beta-2 sea < 8 mg/dL en la primera vesicopunción, omitiendo realizar una segunda vesicopunción.

A Case of in-utero Vesicoamniotic Shunting and Postnatal Vesicostomy in Very Low Birth Weight Baby with Posterior Urethral Valve Syndrome

We present a case of in-utero vesicoamniotic shunting and postnatal vesicostomy in a very low birth weight baby with posterior urethral valve syndrome. He was diagnosed as posterior urethral valve at 24(+5) weeks' gestation. Because of severe hydronephrosis and oligohydroamnios, the shunt was established by basket-shaped catheter at 27(+0) weeks' gestation. After shunt, hydronephrosis improved. At 29(+4) weeks' gestation, the shunt catheter escaped from its position and severe urinary ascites and hydronephrosis developed. At 30 weeks' gestation, the baby was born and showed elevated BUN and creatinine. On the 10th day of birth, vesicostomy was done for urinary drainage. Thereafter, the baby has been followed up for 10 months and has had recurrent episodes of urinary infection. We report the case with a brief review of literature.

In-utero fetal therapy of posterior urethral valve syndrome: A case of vesicoamniotic shunting using a basket-shaped catheter / 대한산부인과학회잡지

We present a case of in-utero treatment of posterior urethral valve syndrome(PUVS) by vesicoamniotic shunting. The shunt was established by basket-shaped catheter at the 22 weeks' gestation. Enlarged bladder and hydronephrosis were improved after the shunt procedure. The baby was delivered at the 39 weeks' gestation and had normal serum range of BUN and creatinine. Because the outer opening of catheter was burried under abdominal skin on the day before delivery, posterior urethral valve excision and basket removal through urethra were operated by endoscopy on the 2nd day of birth. The baby has been followed up for 5 months and in good health. We report this case with a brief review of literature. Shunt operation in-utero is considered as a safe and effective therapy for lower urinary tract obstruction caused by PUVS.