Prenatal Screening Using Maternal Markers

Very elevated hCGβ (≥10 multiple of the median) in maternal marker screening for Down syndrome: Frequency, etiologies, outcomes, and guidelines

AIM

This aim of this study was to detail maternal and fetal anomalies observed on a national scale in a large French cohort of patients presenting high hCG values (≥10 multiple of the median [MoM]) at Down syndrome screening in order to define clear and optimal guidelines.

METHODS

This is a retrospective multicenter study based on a French annual database of all trisomy 21 screenings. Our study targeted and studied cases with hCG or hCGβ values ≥10 MoM. Complementary exams and outcomes were analyzed.

RESULTS

The calculated frequency was 0.05% for hCGβ ≥10 MoM in unselected patients. For this series of 289 cases, a complication of the pregnancy or a poor outcome was observed in 145 cases (51%) as follows: 96 (66%) cases of fetal disease, 23 (16%) of maternal disease, 5 (3.5%) of placental anomalies and 21 (14.5%) of systemic disease concerning mother, fetus and placenta.

CONCLUSION

This study establishes the frequency of hCG or hCGβ values ≥10 MoM, presents a flow chart that optimizes follow-up, and gives clear information for patients presenting with such abnormal values at trisomy 21 screening.

Recent Advances in the Prevention and Screening of Preeclampsia

Throughout the history of medicine, preeclampsia has remained an enigmatic field of obstetrics. In 2023, despite its prevalence and impact, preeclampsia's exact cause and effective treatment remain elusive; the current options are limited to delivery. The purpose of this review is to summarize the knowledge of the possible novel prophylactic therapies and screening methods for preeclampsia, thereby providing valuable insights for healthcare professionals and researchers. Aspirin and LMWH have already been widely used; meanwhile, calcium, vitamin D, and pravastatin show promise, and endothelin receptor antagonists are being explored. Stress reduction, dietary changes, and lifestyle modifications are also being investigated. Another interesting and fast-growing area is AI- and software-based screening methods. It is also key to find novel biomarkers, which, in some cases, are not only able to predict the development of the disease, but some of them hold promise to be a potential therapeutic target. We conclude that, while a definitive cure for preeclampsia may not be eligible in the near future, it is likely that the assessment and enhancement of preventive methods will lead to the prevention of many cases. However, it is also important to highlight that more additional research is needed in the future to clarify the exact pathophysiology of preeclampsia and to thus identify potential therapeutic targets for more improved treatment methods.

“Spinal Dysraphism Spectrum: A Novel Protocol-based Approach for Accurate Diagnosis on Imaging”

The spectrum of spinal dysraphism includes various congenital anomalies of the spinal column and spinal cord. Clinical manifestations are varied and range from paraparesis, gastrointestinal, genitourinary, and musculoskeletal anomalies to asymptomatic cases depending on the level and extent of spinal involvement. Magnetic resonance imaging is the gold standard for assessing these complex spinal anomalies. Even for the experienced radiologist, diagnosis can be challenging in complex cases. It is essential to be aware of the normal embryological developmental stages of the spine for an adequate understanding of the complex anatomy, pathogenesis, and cliniconeuroradiological classification of spinal dysraphism, which is necessary for accurately diagnosing each case as a particular pathological entity. In this pictorial essay, we have depicted the stages and process of spinal embryogenesis, cliniconeuroradiological classification, and the imaging spectrum of spinal dysraphism. As the confusing terminologies and the numerous variants can potentially lead to misdiagnosis, we have proposed a step-wise protocol-based imaging approach to analyze each case and arrive at the correct diagnosis systematically. This would be particularly helpful in confusing and difficult cases, as accurate and early diagnosis is crucial for appropriate patient management.

Second trimester maternal serum biomarkers and the risk of cerebral palsy

AIMS

To investigate whether second trimester maternal serum screening (2TMSS) biomarkers are associated with cerebral palsy (CP) and identify CP characteristics associated with abnormal biomarker levels.

METHOD

In this retrospective case-control data linkage study, we linked mothers of 129 singleton CP cases from a population register to their 2TMSS records and selected 10 singleton pregnancy controls per case (n = 1290). We compared mean and abnormal levels of alpha-fetoprotein (AFP), beta subunit of human chorionic gonadotrophin (β-hCG), unconjugated estriol (uE3), and inhibin between cases and controls and within CP subgroups.

RESULTS

Compared to control pregnancies, CP pregnancies had higher mean levels of AFP (1.10 vs. 1.01 multiple of the population median [MoM], p = 0.01) and inhibin (1.10 vs. 0.98 MoM, p ≤ 0.01). CP pregnancies were 2.5 times more likely to be associated with high levels of AFP (OR 2.52 [95% confidence interval [CI] 1.30, 4.65]; p < 0.01) and 2.6 times for inhibin (OR 2.63 [95% CI 1.37, 4.77]; p < 0.01), and 6.8 times when AFP and inhibin were both elevated (OR 6.75 [95% CI 2.41, 18.94]; p < 0.01). In CP cases, high AFP and high inhibin levels were associated with preterm birth and low birthweight.

INTERPRETATION

Abnormal second-trimester biomarker levels suggest abnormal placentation plays a role in the causal pathway of some CP cases.

Clinical Validation of Novel Chip-Based Digital PCR Platform for Fetal Aneuploidies Screening

Fetal aneuploidy is routinely diagnosed by karyotyping. The development of techniques for rapid aneuploidy detection based on the amplification reaction allows cheaper and rapid diagnosis. However, the currently available solutions have limitations. We tested a novel approach as a diagnostic tool in clinical practice. The objective of this study was to provide a clinical performance of the sensitivity and specificity of a novel chip-based digital PCR approach for fetal aneuploidy screening. The study was conducted in 505 pregnant women with increased risk for fetal aneuploidy undergoing invasive prenatal diagnostics. DNA extracted from amniotic fluid or CVS was analyzed for the copy number of chromosomes 13, 18, 21, X, and Y using a new chip-based solution. Performance was assessed by comparing results with findings from karyotyping. Aneuploidy was confirmed in 65/505 cases positive for trisomy 21, 30/505 cases positive for trisomy 18, 14/505 cases positive for trisomy 13 and 21/505 with SCAs. Moreover, 2 cases with triploidy and 2 cases with confirmed mosaicisms of 21 and X chromosomes were detected. Clinical sensitivity and specificity within this study was determined at 100% for T21 (95% CI, 99.26–100%), T18 (95% CI, 99.26–100%), and T13 (95% CI, 99.26–100%). Chip-based digital PCR provides equally high sensitivity and specificity in rapid aneuploidy screening and can be implemented into routine prenatal diagnostics.

First-trimester maternal serum biomarkers and the risk of cerebral palsy

AIM

To investigate whether combined first-trimester screening (cFTS) biomarkers are associated with cerebral palsy (CP) and to identify CP characteristics associated with abnormal biomarker levels.

METHOD

In this retrospective case-control data linkage study, we matched mothers of 435 singletons with CP from a population register to their cFTS records and selected 10 singleton pregnancy controls per case. We compared mean and abnormal levels (expressed as multiples of the median [MoMs]) of pregnancy-associated plasma protein-A (PAPP-A), beta subunit of human chorionic gonadotrophin (β-hCG), and nuchal translucency between cases and controls and between CP subgroups.

RESULTS

Compared with control pregnancies, CP pregnancies had lower mean levels of PAPP-A (0.95 vs 1.01 MoM, p=0.02) and β-hCG (0.93 vs 0.99 MoM, p=0.02). Biomarker levels in CP pregnancies were 1.8 times more likely to be associated with abnormally low levels of PAPP-A (p<0.01), 1.4 times for β-hCG (p=0.12), and 2.6 times for low PAPP-A and β-hCG together (p=0.04). In cases with CP, an abnormally low PAPP-A level was associated with moderate preterm birth, low Apgar scores, and Gross Motor Function Classification System level V. Low β-hCG was associated with very low birthweight.

INTERPRETATION

Low first-trimester biomarker levels suggest a role for early pregnancy factors in some causal pathways to CP.

WHAT THIS PAPER ADDS

Low first-trimester levels of biomarkers in maternal serum are associated with later cerebral palsy (CP). Early pregnancy factors have potential importance in causal pathways to CP. Causal pathways involving preterm birth, term neonatal encephalopathy, and genetic syndromes may be implicated.

Prenatal serum screening - a summary of our experience with high risk reporting

Objective: The spectrum of pregnancy tests for screening of chromosomal disorders in the unborn child includes maternal serum testing through double, triple and quadruple marker as well as the emerging cell free fetal DNA analysis based noninvasive prenatal test. The aim of this short communication is to summarize our finding's pertaining to high risk serum screening cases with reference to clinical indications and history.Methods: Data of cases reported high-risk by serum screening including a total of 3368 women with median age of 32 years was included. Serum testing was done in the laboratory using the technology of Chemiluminescence micro particle two-step immunoassay for sensitive quantification of hormones routinely tested for in the double, triple and quadruple marker. Risk estimation using values of hormone levels and the resulting MoM was done using the PRISCA 5.0.2.37.Results: A total of 16,608 samples were tested for serum screening in the study period and specific high risk analysis detected a total of 20% reported as high risk. Trisomy 21 was detected to be the most common finding at 86% followed by neural tube defects at 9%. Advanced maternal age (≥35 years) accounted for a total of 34% of the reported high risk cases.Conclusion: The gap between absence of a nation-wide screening mandate, and guidelines for agencies involved in prenatal screening tests can be reduced with studies which focus on trends in recommendation and developing an understanding of the clinical backdrop leading to high risk screening results.