The natural history of pregnancies with prenatal diagnosis of Trisomy 18 or Trisomy 13: Retrospective cases of a 23-year experience in a Brazilian public hospital

Conducta médica frente al diagnóstico prenatal de trisomía 18: ¿se aproxima un cambio de paradigma?

El objetivo del trabajo es analizar dos conductas médicas opuestas en la vida prenatal de los niños con trisomía 18: el aborto y los cuidados paliativos perinatales. Se realizó una búsqueda bibliográfica en PubMed a partir de los términos “trisomy 18”, “abortion” y “palliative care”. Actualmente, están cambiando las conductas médicas dirigidas a los niños nacidos con trisomía 18, debido a que ya no se la considera una enfermedad incompatible con la vida. Este cambio de paradigma en la conducta médica posnatal debería reflejarse en la conducta prenatal, para ofrecer a los padres alternativas distintas al aborto. Los cuidados paliativos fetales y perinatales constituyen una respuesta ética válida para el tratamiento de niños con trisomía 18.

Congenital diaphragmatic hernia in a middle-income country: Persistent high lethality during a 12-year period

BACKGROUND

In high- and middle-income countries, mortality associated to congenital diaphragmatic hernia (CDH) is high and variable. In Brazil, data is scarce regarding the prevalence, mortality, and lethality of CDH. This study aimed to analyze, in São Paulo state of Brazil, the temporal trends of prevalence, neonatal mortality and lethality of CDH and identify the time to CDH-associated neonatal death.

METHODS

Population-based study of all live births with gestational age ≥ 22 weeks, birthweight ≥400g, from mothers residing in São Paulo State, Brazil, during 2004-2015. CDH definition and its subgroups classification were based on ICD-10 codes reported in the death and/or live birth certificates. CDH-associated neonatal death was defined as death up to 27 days after birth of infants with CDH. CDH prevalence, neonatal mortality and lethality were calculated and their annual percent change (APC) with 95% confidence intervals (95%CI) was analyzed by Prais-Winsten. Kaplan-Meier estimator identified the time after birth that CDH-associated neonatal death occurred.

RESULTS

CDH prevalence was 1.67 per 10,000 live births, with a significant increase throughout the period (APC 2.55; 95%CI 1.30 to 3.83). CDH neonatal mortality also increased over the time (APC 2.09; 95%CI 0.27 to 3.94), while the lethality was 78.78% and remained stationary. For isolated CDH, CDH associated to non-chromosomal anomalies and CDH associated to chromosomal anomalies the lethality was, respectively, 72.25%, 91.06% and 97.96%, during the study period. For CDH as a whole and for all subgroups, 50% of deaths occurred within the first day after birth.

CONCLUSIONS

During a 12-year period in São Paulo State, Brazil, CDH prevalence and neonatal mortality showed a significant increase, while lethality remained stable, yet very high, compared to rates reported in high income countries.

First Trimester Screening Tests Pregnancy and Trisomy 13 Syndrome, Sex Chromosome Aneuploidy in Iran: A Cross-Sectional Study

BACKGROUND

Trisomy 13 (T13) and sex chromosome aneuploidies (SCA) are the vital causes of congenital malformations. This study was performed to identify the T13 and SCA with screening tests in the first trimester of pregnancy.

MATERIALS AND METHODS

In this cross-sectional study, first-trimester combined screening was conducted on 2100 pregnant women referred to Narges Genetics Laboratory, Ahvaz, Iran. Evaluating the first trimester screening tests, including nuchal translucency (NT), crown-rump length (CRL) and pregnancy-associated plasma protein-A (PAPP-A), and free beta of human chorionic gonadotropin (fβhCG) was performed. For a definitive diagnosis of T13 and SCA syndrome, fetal karyotype was evaluated.

RESULTS

The average NT and CRL in high-risk group for T13 were 5.96 mm and 61.7 mm respectively and in high-risk groups for SCA were 3.7 mm and 75.9 mm, respectively. Significant correlation was observed among NT, CRL and T13, SCA (P<0.05). The average serum fβhCG and PAAP-A levels in high-risk group for T13 were 0.42 and 0.31, respectively. Significant correlation was observed between decrease fβhCG, PAPP-A and T13 levels and increase fβhCG levels and SCA levels (P<0.05). No Significant correlation was observed between PAPP-A levels and SCA levels (P>0.05).

CONCLUSION

Using special software and karyotype testing, the prenatal screening tests based on the maternal age and gestational age in the first trimester of pregnancy may determine the major risk of fetal chromosomal abnormalities.

Umbilical artery pulsatility index and half-peak systolic velocity in second- and third-trimester fetuses with trisomy 18 and 13

OBJECTIVES

To analyze umbilical artery (UA) Doppler velocimetry and its possible role in placenta-mediated fetal growth restriction (FGR) in second- and third-trimester fetuses with trisomy 18 and 13.

METHODS

UA pulsatility index (PI) and half-peak systolic velocity deceleration time (hPSV-DT) were measured in fetuses with trisomy 18 and 13. Correlation with gestational age, birthweight, and perinatal outcome was analyzed.

RESULTS

A total of 80 measurements were taken from 33 fetuses with trisomy 18 and 19 with trisomy 13. Overall, there was a high prevalence of abnormal UA Doppler velocimetry. In fetuses with trisomy 18, 54% (27/50) of the UA PI values and 58% (29/50) of the UA hPSV-DT values were abnormal. In fetuses with trisomy 13, 80% (24/30) of the UA PI values and 87% (26/30) of the UA hPSV-DT values were abnormal. The prevalence of abnormal UA Doppler velocimetry increased with gestational age in both types of aneuploidy. However, this trend was only significant for trisomy 13 (p<0.05). All fetuses with trisomy 18 and 86% of fetuses with trisomy 13 were classified at birth as FGR. There were no perinatal survivors in this series.

CONCLUSIONS

A high prevalence of abnormal UA Doppler velocimetry was found in second- and third-trimester fetuses with trisomy 18 and 13, which further increased with gestational age. These results may well correlate with alterations described previously in the placenta, suggesting placental insufficiency has an important role in the development of FGR in these autosomal aneuploid fetuses.

A visual tool inclusive of fetal ultrasound and autopsy findings to reach a balanced approach to counseling on trisomy 18 in early second trimester

Identified by the eponym "Edwards' Syndrome," trisomy 18 (T18) represents the second most common autosomal trisomy after T21. The pathophysiology underlying the extra chromosome 18 is a nondisjunction error, mainly linked with the advanced maternal age. More frequent in female fetuses, the syndrome portends high mortality, reaching a rate of 80% of miscarriages or stillbirths. The three-step evaluation includes first trimester screening for fetal aneuploidy using a combination of maternal age, fetal nuchal translucency thickness, fetal heart rate and maternal serum free ß-hCG and PAPP-A; followed by the research for fragments of fetal DNA in maternal blood; and, finally, invasive techniques leave to the established diagnosis. Starting with the first trimester scan, selected ultrasound findings should be investigated to define not only the impact of the genetic problem on the fetus, but also to address the prenatal counseling. Previous series underline that T18 is not uniformly lethal. An active dialogue on the choices in the management of infants with T18 has emerged, sustained by the transition from the comfort care to the intervention attitude. Survival rates for individuals with supposedly fatal conditions have increased. In this novel scenario, an ad hoc counseling is pivotal. To support it, a comparative analysis by pictorial assays between ultrasound and autopsy findings could be beneficial. We provide an illustrative tool from a clinical case managed in early second trimester, with the purpose to strive a balanced approach in the hard choice faced by couples of fetuses with T18.

First-trimester presentation of ultrasound findings in trisomy 13 and validation of multiparameter ultrasound-based risk calculation models to detect trisomy 13 in the late first trimester

OBJECTIVES

To identify the most common ultrasound patterns of markers and anomalies associated with Patau syndrome (PS), to explore the efficacy of multiparameter sonographic protocols in detecting trisomy 13 (T13) and to analyze the influence of maternal age (MA) on screening performance.

METHODS

The project was a prospective study based on singleton pregnancies referred for a first-trimester screening examination. The scan protocol included nuchal translucency (NT), fetal heart rate (FHR), secondary ultrasound markers [nasal bone (NB), tricuspid regurgitation (TR), ductus venosus reversed a-wave (revDV)] and major anomaly findings.

RESULTS

The study population comprised 6133 pregnancies: 6077 cases of euploidy and 56 cases of T13. Statistically significant differences were found in MA, FHR, NT, absence of NB, presence of revDV, TR and single umbilical artery. Fourteen cases of T13 (25%) demonstrated no markers of aneuploidy. The best general detection rate (DR) (DR of 78.6% with an false positive rate (FPR) of 1.2%) was obtained for a cutoff of 1/300 utilizing the "NT+T13" algorithm. The logistic regression model revealed that the central nervous system (CNS) anomalies had the greatest odds ratio (of 205.4) for T13.

CONCLUSIONS

The effectiveness of the multiparameter sonographic protocol used for T13 screening showed promising results in patients older than 36 years and suboptimal results in patients between 26 and 36 years old. When screening for T13 left heart defects, CNS anomalies, abdominal anomalies, FHR above the 95th percentile, increased NT, revDV and lack of NB should receive specific attention.