St. Lucia pilots Newborn Screening Programme for Sickle Cell Disease

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Since 2010, the SickKids-Caribbean Initiative (SCI) has formalised partnerships between paediatric cancer/blood diseases specialists at SickKids and Caribbean professionals, through training and education, to support the early identification and optimal treatment of Caribbean children with these disorders. Additionally, through collaboration with the University of the West Indies, local Ministries of Health and hospitals, and the private sector, SCI has realised financial support to improve infrastructure, assist the development of locally-appropriate treatment standards, and heighten advocacy.

SickKids-Caribbean Initiative (SCI): enhancing capacity for care in paediatric cancer and blood disorders.
SickKids-Caribbean Initiative (SCI): enhancing capacity for care in paediatric cancer and blood disorders.
SCI has since moved a step further: in February of this year, a pilot project in Saint Lucia and Jamaica focused on improving newborn screening (diagnosis, treatment and monitoring) for Sickle Cell Disease (SCD), the most common genetic disorder in these islands.

The SickKids-Caribbean Initiative (SCI): enhancing capacity for care in paediatric cancer and blood disorders, is a not-for-profit collaboration between the Hospital for Sick Children (SickKids) in Toronto, Canada, and six countries in the Caribbean, that strives to improve the outcomes and quality of life for children with cancer and blood disorders.

Early diagnosis of SCD is essential to prevent severe illness and early deaths. Laboratory newborn screening for SCD is a worldwide recommended standard of care since simple cost-effective interventions, such as daily antibiotic usage and special vaccines, can do much to prevent this early illness and death, and clear signs and symptoms of the disease are typically delayed until 6 months of age or later (due to the relative protection of fetal (HbF) haemoglobin).

In the Caribbean, a limited Jamaican screening programme became established in 1973 and Saint Lucia commenced universal screening in April 1990 through the efforts of the St. Lucia Sickle Cell Association. The other English-speaking Caribbean islands have not yet commenced routine newborn screening.

The fact that St. Lucia already has a national newborn screening programme for SCD makes it an ideal candidate for the pilot, and as there are concerns related to the method which utilises blood from the umbilical cord (a mix of both baby and mother’s blood) which may account for errors in diagnosis, as well as to the efficiency and relative cost of the testing method, we stand to benefit further from the information provided by the pilot.

Beginning with St. Lucia and Jamaica, and then expanding to other SCI participating countries, the project aims to centralise the SCD newborn screening tests, through the Tropical Metabolism Research Unit in Kingston, Jamaica. Instead of the current umbilical cord blood collection method, the pilot uses a dry filter paper blood spot method, with samples obtained directly from the newborn by a heel prick. The filter paper samples are then transported to Jamaica for analysis.

Reporting of results will be done electronically to ensure timely identification of screen-positive infants who need early intervention and ongoing care.

The project is being rolled out in two phases: for the first 6 months, the existing cord blood sampling system with local laboratory analysis will run concurrently with the dried blood spot method, local collection and analysis in Jamaica. Comparison will be made between the two systems in acceptability, diagnostic accuracy, cost, turn-around time and delivery of results. Conditional upon successful implementation of the dried blood and centralised lab testing system, phase 2 (months 7-12) of the project will commence with complete replacement of the wet cord blood system with the validated dried blood spot system.

The anticipated benefits of the new method, and of the consolidated and centralised testing, are several: improved diagnostic accuracy, lower cost due to higher volumes and improved efficiency, and also this method lends itself to future expansion of the newborn screening panel beyond SCD to other disorders such as congenital hypothyroidism, congenital adrenal hyperplasia and certain metabolic disorders.

This communication exercise aims to ensure that all stakeholders understand why and how this pilot is being conducted, and follows HCW (nurses, midwives, doctors) training to ensure proper dried blood spot collection and handling techniques, and to properly prepare staff, as well as families, to support and accept the new screening protocol. Any screening programme designed to improve national health should be reviewed and compared to international standards to confirm that the best is being achieved. The lessons learnt from this pilot will help to reconcile our local discrepancies in the frequencies of the different forms of SCD, and compare the accuracy of cord blood diagnosis to the new method, with a view to developing a more accurate and comprehensive programme to assist the children of St. Lucia with SCD. We expect this approach of centralising diagnostic capability will benefit the region through lower costs and enhanced availability and accessibility of newborn screening diagnostics.