Down Syndrome Screening in India: Are We There Yet?

Non-Invasive Prenatal Testing (NIPT): Reliability, Challenges, and Future Directions

Non-invasive prenatal testing was first discovered in 1988; it was primarily thought to be able to detect common aneuploidies, such as Patau syndrome (T13), Edward Syndrome (T18), and Down syndrome (T21). It comprises a simple technique involving the analysis of cell-free foetal DNA (cffDNA) obtained through maternal serum, using advances in next-generation sequencing. NIPT has shown promise as a simple and low-risk screening test, leading various governments and private organizations worldwide to dedicate significant resources towards its integration into national healthcare initiatives as well as the formation of consortia and research studies aimed at standardizing its implementation. This article aims to review the reliability of NIPT while discussing the current challenges prevalent among different communities worldwide.

Relationship between trunk muscle strength, reaching ability and balance in children with Down syndrome - A cross-sectional study

BACKGROUND

Children with Down Syndrome (DS) present with neuromuscular disturbances leading to delayed developmental milestones, poor quality of movement and poor balance. The aim of this study is to discuss the role of trunk muscle strength in the functional performance of children with DS.

METHODOLOGY

28 children were recruited in the study, 14 with DS and 14 age and gender-matched controls. Trunk muscle strength, reaching ability and balance were assessed using a Handheld Dynamometer, Modified Functional Reach test and Pediatric Balance Scale, respectively.

RESULTS

Children with DS present with poorer trunk muscle strength, reaching ability and balance as compared to typically developing (TD) children. There was a positive correlation between trunk muscle strength and lateral reaching in children with DS. A strong to moderate correlation was observed between the trunk muscle strength and balance in children with DS.

DISCUSSION

Children with DS demonstrated a significantly weak trunk muscle groups. Lateral reaching distance is reduced due to the poor proximal control and they present with near-normal forward reach distance attributed to compensation using the lower trunk muscles. They exhibit poor balance in the components that require a small base of support.

CONCLUSION

Children with DS exhibit weak trunk muscles along with lesser reaching distance and poor balance. Also, trunk muscle strength influences lateral reaching ability. Trunk muscle strength, mainly trunk extensors impacted functional balance in sitting, standing and while performing transfers.

Ethnic-specific reference range affects the efficacy of quadruple test as a universal screening for Down syndrome in a developing country

Objective

To evaluate the efficacy of the quadruple test for potential use as a Thai national policy for Down syndrome (DS) screening and establish an accurate equation for risk estimation of Down syndrome based on gestational age, weight and the ethnic-specific reference range of our population.

Methods

A prospective study was conducted on singleton pregnancies at 14 to 21 weeks of gestation to evaluate the efficacy of quadruple DS screening using the automatically calculated Western European descent factor (WF) in our population and the impact of screening using a specific Thai ethnic factor as well as to establish an equation for the risk estimation of DS based on gestational age, weight and a local Thai ethnic factor to correct for the impact of ethnic factor on the screening efficacy.

Results

Of a total of 5,515 women, 12 cases of DS and 8 cases of other aneuploidies were found. The detection rate, false positive rate and specificity were 75.0%, 9.1% and 90.9%, respectively, by automatic calculation with the widely used WF; the screening efficacy was lower when used in Asian populations than in other studies. The best-fitted regression equation of serum quadruple screening of AFP, free β-hCG, uE3 and inhibin A was established by adjustment for gestational age (GA) in days, maternal weight and our Thai-specific ethnic reference range which was created for this study. Calculations with our Thai-specific ethnic model gave a better detection rate of 83.3%, a false positive rate of 9.6% and specificity of 90.4%.

Conclusion

The serum quadruple test had a lower detection rate than expected when the risk estimation was based on the WF reference range. The serum quadruple test using WF had significantly different levels when corrected with our ethnic-specific factor. Using our local ethnic specific model could increase the detection rate of DS screening in Thailand with a minimal increase in false positive rates. Our findings indicate that DS screening should be adjusted with an appropriate individual ethnic factor when used for national screening.

The Emergence and Global Spread of Noninvasive Prenatal Testing

Since its introduction in 2011, noninvasive prenatal testing (NIPT) has spread rapidly around the world. It carries numerous benefits but also raises challenges, often related to sociocultural, legal, and economic contexts. This article describes the implementation of NIPT in nine countries, each with its own unique characteristics: Australia, Canada, China and Hong Kong, India, Israel, Lebanon, the Netherlands, the United Kingdom, and the United States. Themes covered for each country include the structure of the healthcare system, how NIPT is offered, counseling needs and resources, and cultural and legal context regarding disability and pregnancytermination. Some common issues emerge, including cost as a barrier to equitable access, the complexity of decision-making about public funding, and a shortage of appropriate resources that promote informed choice. Conversely, sociocultural values that underlie the use of NIPT vary greatly among countries. The issues described will become even more challenging as NIPT evolves from a second-tier to a first-tier screening test with expanded use.

Correlates of knowledge of genetic diseases and congenital anomalies among pregnant women attending antenatal clinics in Lagos, South-West Nigeria

Introduction

genetic diseases and congenital anomalies place a significant burden on the health of new-borns and their mothers. Despite the availability of a variety of prenatal screening tests, mothers' knowledge has been documented to determine uptake. This study aims to assess the knowledge of pregnant women about birth defects and the associated correlates with regard to willingness to do prenatal screening.

Methods

a cross-sectional descriptive study was conducted among 422 antenatal mothers recruited sequentially as they attended antenatal clinics at the Lagos University Teaching Hospital. An interviewer-administered questionnaire was used to determine their knowledge of birth defects and willingness to do prenatal testing.

Results

majority of the participants (92.2%) had at least secondary education. The mean total knowledge score of the respondents was 63%. Age and knowledge scores were not significantly correlated (r=-0.071, p=0.14). Being employed predicted higher knowledge scores (95% CI: 0.09, 2.09, p=0.03). Respondents who had primary school education and those who replied “I don't know” to willingness to test had significantly lower knowledge scores (95% CI: -15.01, -1.19, p=0.02 and 95% CI: -4.52, -0.68, p=0.01 respectively). Majority (79.1%) of the respondents were willing to undergo testing. Respondents' level of education was significantly associated with willingness to test (p=0.03).

Conclusion

the observed knowledge gaps were considerable. There is need for improvement in education, the empowerment of women and access to quality healthcare including prenatal screening.