Haemoglobinopathies in India: estimates of blood requirements and treatment costs for the decade 2017-2026

Genetic Screening-Emerging Issues

In many countries, some form of genetic screening is offered to all or part of the population, either in the form of well-organized screening programs or in a less formalized way. Screening can be offered at different phases of life, such as preconception, prenatal, neonatal and later in life. Screening should only be offered if the advantages outweigh the disadvantages. Technical innovations in testing and treatment are driving changes in the field of prenatal and neonatal screening, where many jurisdictions have organized population-based screening programs. As a result, a greater number and wider range of conditions are being added to the programs, which can benefit couples' reproductive autonomy (preconception and prenatal screening) and improve early diagnosis to prevent irreversible health damage in children (neonatal screening) and in adults (cancer and cascade screening). While many developments in screening are technology-driven, citizens may also express a demand for innovation in screening, as was the case with non-invasive prenatal testing. Relatively new emerging issues for genetic screening, especially if testing is performed using DNA sequencing, relate to organization, data storage and interpretation, benefit-harm ratio and distributive justice, information provision and follow-up, all connected to acceptability in current healthcare systems.

Genetic counseling in sickle cell disease: Insights from the Indian tribal population

Sickle cell disease (SCD) is an inherited disorder of hemoglobin. With an overall prevalence of 4.3%, India is the second-largest hub of SCD after Africa. Genetic counseling (GC) is the most cost-effective intervention to reduce the burden of a genetic disease including SCD. Even though GC's role in reducing SCD birth prevalence is well established, it is still not incorporated into Indian national policy and is unavailable to most Indians approaching their marriageable age and childbirth. GC perception and efficacy have also not been explored yet among young adults, especially in Indian tribal communities. Counseling in these communities requires careful consideration of their socioeconomic, cultural, and ethical values. Community engagement with local tribes and healthcare infrastructure in a multitier approach is essential for an effective GC. This review aims to provide healthcare providers and genetic counselors with the essentials of GC in the prevention and management of SCD among tribal communities based on the author's counseling experience in South India.

Thalassemia in India

Management and control of hemoglobinopathies are a challenge in India where 67.0% of people reside in rural regions. The GDP spent on health is one of the lowest (1.3%) resulting in high out-of-pocket expenses. The β-thalassemias are prevalent with an estimated 7500-12000 new births each year. Hb S (HBB: c.20A>T) and Hb E (HBB: c.79G>A) are also common regionally. Over 80 β-thalassemia (β-thal) mutations have been characterized in Indians. The δ gene mutations are increasingly being described and their coinheritance in β-thal carriers leads to a reduction in Hb A₂ levels and a misdiagnosis of carriers. Around 15-20 centers offer prenatal diagnosis (PND) mainly in urban regions. The projected annual cost of care of β-thal patients over a decade (2016-2026) will increase from INR30,000 (US$448) million to INR55,000 (US$820) million if all patients are adequately treated. Cost comparisons are difficult to make with other international studies as the standard of care, cost of medicines and other services vary in different countries. Several centers provide hematopoietic stem cell transplants (HSCTs) for thalassemias, however, only around 250 HSCTs are done annually. Although the cost is high, financial assistance is available for a few patients. There are disparities in the quality of care and to address this a National Policy has been proposed for the management and prevention of hemoglobinopathies that will embark on a comprehensive program, providing adequate care and augmenting the existing public health care services. It will also include training, genetic counseling and easier access to preventive options and a National Registry.

Undiagnosed haemoglobinopathies among pregnant women attending antenatal care clinics in Pune, India

Pregnant women with iron deficiency and those who are carriers of haemoglobinopathies present with anaemia of varying severity. There is no antenatal screening for haemoglobinopathies in India. The objective of this study was to determine the prevalence of undiagnosed haemoglobinopathy carriers in a random sample of pregnant women attending antenatal care clinics in Pune city, India. Biobanked DNA of 360 randomly selected pregnant women was genotyped for six common mutations and two common haemoglobin variants, HbS and HbE. Odds ratios (OR) with 95% confidence intervals were computed to determine association of carrier status with socio-demographic, haematological and clinical characteristics. The prevalence of undiagnosed haemoglobinopathy carriers was 6.3% (95% CI 4.2-9.4%) of which 3.3% (95% CI 1.9-5.7%) were beta thalassaemia carriers. There was an increased odds that beta thalassaemia carriers had moderate anaemia (OR 10.59, 95% CI 1.15-96.90). This study reveals the high prevalence of undiagnosed haemoglobinopathy carriers among pregnant women, indicating the need to immediately implement carrier screening and genetic counselling services across the country.

Sickle cell disease in India: a scoping review from a health systems perspective to identify an agenda for research and action

INTRODUCTION

Sickle cell disease (SCD) disproportionately impacts Adivasi (tribal) communities in India. Current research has focused on epidemiological and biomedical aspects but there has been scarce research on social determinants and health systems aspects. Given its fragmented distribution, resources and programmes have emerged in west and central India. This scoping review seeks to identify geographical and evidence gaps for action on SCD from a health systems lens.

METHODS

We followed a scoping review protocol, using Google Scholar and PubMed for published literature. Keywords used included sickle cell anaemia/disease, health systems, tribal and India. We used Google search for grey literature. We compiled a list of 55 records (of which 35 were retained), with about half pertaining directly to India and others relevant to similar settings. Results were organised and analysed using the WHO health systems framework to identify geographical and evidence gaps.

RESULTS

We found substantial literature on biomedical and clinical aspects of SCD but little on the design and implementation of programmes in community and Adivasi-specific contexts as well as on social determinants of SCD. There were regional gaps in knowledge in southern and northeast India. Wherever community-based programmes exist, they have originated in civil society initiatives and relatively limited state-led primary healthcare-based efforts pointing to weak agenda setting.

CONCLUSION

Both research and action on SCD especially among tribal populations need immediate attention. While geospatial epidemiology has been well understood, gaps remain in context-specific knowledge for action in several parts, as well as evidence gaps across several health system building blocks, including governance and financing of care. Despite publication of a draft policy, delayed adoption and lapses in implementation have limited the response largely to local communities and non-governmental organisations.

Neonatal and carrier screening for rare diseases: how innovation challenges screening criteria worldwide

Screening for rare diseases first began more than 50 years ago with neonatal bloodspot screening (NBS) for phenylketonuria, and carrier screening for Tay-Sachs disease, sickle cell anaemia and β-thalassaemia. NBS's primary aim is health gain for children, while carrier screening enables autonomous reproductive choice. While screening can be beneficial, it also has the potential to cause harm and thus decisions are needed on whether a specific screening is worthwhile. These decisions are usually based on screening principles and criteria. Technological developments, both treatment driven and test driven, have led to expansions in neonatal screening and carrier screening. This article demonstrates how the dynamics and expansions in NBS and carrier screening have challenged four well-known screening criteria (treatment, test, target population and programme evaluation), and the decision-making based on them. We show that shifting perspectives on screening criteria for NBS as well as carrier screening lead to converging debates in these separate fields. For example, the child is traditionally considered to be the beneficiary in NBS, but the family and society can also benefit. Vice versa, carrier screening may be driven by disease prevention, rather than reproductive autonomy, raising cross-disciplinary questions regarding potential beneficiaries and which diseases to include. In addition, the stakeholders from these separate fields vary: Globally NBS is often governed as a public health programme while carrier screening is usually available via medical professionals. The article concludes with a call for an exchange of vision and knowledge among all stakeholders of both fields to attune the dynamics of screening.

Hydroxyurea and blood transfusion therapy for Sickle cell disease in South Asia: inconsistent treatment of a neglected disease

Background

Hydroxyurea and blood transfusion therapies remain the main therapeutic strategies for Sickle cell disease. Preliminary data suggest substantial variation and inconsistencies in practice of these two therapeutic modalities in South Asia. In this systematic review we searched Medline, Cochrane library and Scopus for articles on usage of hydroxyurea and blood transfusion therapies for sickle cell disease in South Asia published in English between October 2005 and October 2020.

Results

We selected 41 papers: 33 from India, 3 from Sri Lanka, 2 each from Pakistan and Bangladesh and one from Nepal. Only 14 prospective trials focused on hydroxyurea therapy from which majority (n = 10; 71.4%) adopted fixed low dose (10 mg/kg/day) regimen. With hydroxyurea therapy, 12 and 9 studies reported significant reductions in vaso-occlusive crises and transfusion requirement respectively. Severe anaemia (haemoglobin level < 6–7 g/dl) was the commonest indicator (n = 8) for transfusion therapy followed by vaso-occlusive crisis.

Conclusions

Published data on the hydroxyurea and transfusion therapies in South Asia are limited and heterogeneous. A clear gap of knowledge exists about the nature of the sickle cell disease in the Indian subcontinent particularly from countries outside India necessitating further evidence-based assessments and interventions.

Evaluation of Paper-Based Point of Care Screening Test for Sickle Cell Disease

The aim of the study is to evaluate the stability and longevity of the paper-based screening test for the sickle cell disease in relation to different temperatures and storage time. Blood stain patterns were interpreted after spotting the blood-buffer mixture (phosphate buffer, saponin and sodium metabisulfite) on chromatographic paper (Whatman no. 3). The stability of the buffer was tested after keeping the buffer at different temperature for 24 h. Longevity of the buffer was tested post storage for various time intervals. Test indicated reproducibility with the buffer stored at 4°C. The 15% metabisulfite buffer was found to be stable up to 180 days at 4°C and showed accurate identification of all genotypes. The tests revealed 100% sensitivity and 100% specificity in identification of HbS. However, the sensitivity of differentiation between sickle cell trait (AS) with disease (SS) was found to be 97.7% with 100% specificity. The paper-based screening test may be used as a method of choice for the screening of sickle cell anemia in community-based screening programs. The low-cost, rapid, and accurate point of care testing tools offer an avenue for effective screening in developing nations.

A decision support scheme for beta thalassemia and HbE carrier screening

The most effective way to combat β-thalassemias is to prevent the birth of children with thalassemia major. Therefore, a cost-effective screening method is essential to identify β-thalassemia traits (BTT) and differentiate normal individuals from carriers. We considered five hematological parameters to formulate two separate scoring mechanisms, one for BTT detection, and another for joint determination of hemoglobin E (HbE) trait and BTT by employing decision trees, Naïve Bayes classifier, and Artificial neural network frameworks on data collected from the Postgraduate Institute of Medical Education and Research, Chandigarh, India. We validated both the scores on two different data sets and found 100% sensitivity of both the scores with their respective threshold values. The results revealed the specificity of the screening scores to be 79.25% and 91.74% for BTT and 58.62% and 78.03% for the joint score of HbE and BTT, respectively. A lower Youden’s index was measured for the two scores compared to some existing indices. Therefore, the proposed scores can obviate a large portion of the population from expensive high-performance liquid chromatography (HPLC) analysis during the screening of BTT, and joint determination of BTT and HbE, respectively, thereby saving significant resources and cost currently being utilized for screening purpose.