Newborn Screening

Background Information

All babies born in England are offered screening for sickle cell when they are between 5 – 8 days old as part of the heel prick blood tests offered to all new born babies. The midwife takes the sample from a heel prick using a sterile needle and blood is spotted onto a blotting paper and sent to the laboratory.

In NW London the sample is sent to Great Ormond Street Hospital (GOSH) and any with suspected unusual haemoglobin including trait or disease or those with an inconclusive result are sent to Central Middlesex Hospital (CMH) for a second line test.

In NW London the result of all babies found to have any unusual haemoglobin are sent to the specialist nurse at Brent Sickle Cell & Thalassaemia Centre.

All newborn babies have a high level of Fetal Haemoglobin (Hb F) at birth, this is irrespective of the type of adult haemoglobin they have inherited from their parents.

If a newborn baby has inherited the genes for normal adult haemoglobin, at birth the blood test result will indicate the presence of haemoglobins F and A, commonly written (Hb FA). Haemoglobin A2 is not usually reported in the newborn screening result, see Haemoglobin.

Babies with a Carrier (Trait)

In NW London if a child is found to be a carrier (trait) the parents are sent an appointment letter for the specialist nurse to either visit them at home or to invite them to a local hospital or centre for counselling in order to explain the result to them and what the result will mean for their child and for other family members.

If the parents have not been tested they are offered testing in order for them to know if they are at-risk of having a child with a disease in future. The child’s older brothers and sisters may or may not be offered testing, this depends on whether they have been tested before or not, the nature of the unusual haemoglobin found and whether they are at-risk of having a disease, the parents will be advised accordingly.

If a newborn baby has inherited the genes for an unusual haemoglobin, for example, sickle cell trait, at birth the blood test result will indicate the presence of haemoglobins F, A and S, commonly written (Hb FAS); haemoglobin C trait the blood test result will indicate the presence of F, A and C, commonly written (Hb FAC).

Babies with an inconclusive result

Sometimes it is difficult for the laboratory to be able to identify the two adult type haemoglobin that a newborn baby has inherited this is because at birth the majority of the baby’s haemoglobin is Fetal (baby) Haemoglobin (F) in which case the baby will need to be retested. Sometimes the baby may have inherited a novel haemoglobin which is difficult to conform in the early stages of after birth it may therefore be necessary to retest the baby when he / she is a little older, usually around four months of age.

In NW London once the baby has been retested the result is sent to the specialist nurse at Brent Sickle Cell & Thalassaemia Centre. The parents are sent an appointment letter for the specialist nurse to either visit the parents at home or to invite them to a local hospital or centre for counselling in order to explain the reason for the retest; the same heel prick method used for the first test is used for the retest but instead of using a blotting paper a few drops of blood is put into a small blood bottle.

Babies with a suspected disease state

Babies with a suspected disease need to be retested in order to confirm the diagnosis.

In NW London the initial result is sent to the specialist nurse at Brent Sickle Cell & Thalassaemia Centre or to the local specialist nurse. The parents are sent an appointment letter for the specialist nurse to either visit them at home or to invite them to a local hospital or centre for counselling in order to explain the reason for retesting the baby. The same heel prick method used for the first test is used for the retest but instead of using a blotting paper a few drops of blood is put into a small blood bottle.

If the child is diagnosed with a disease

If the result confirms that the child has got a disease the parents are seeing again to inform them of the final result, they are given information about the condition found, advised on how to care for the child in order to prevent complications and what to do in an emergency.

If a newborn baby has inherited the genes for a disease, for example, sickle cell anaemia at birth the blood test result will indicate the presence of haemoglobin F and S commonly written (Hb FS); or sickle haemoglobin C disease the blood test result will indicate the presence of haemoglobin F, S and C, commonly written (Hb FSC), the result will depend on which two haemoglobins the child has taken from both parent.

The child’s parents are given any recommended educational material available these will give them more information about the condition and how to look after their child. If they agree or request it they may be introduced to other parents who have experience of caring for a child with the same or similar condition to their child; they are also told about any available local parent’s support groups and voluntary organisations.

The child’s GP and health visitor are informed of the diagnosis and the child is referred to the local hospital for specialist care. A hospital appointment is usually received from the hospital for the child to be seen by the time the child is two months old; this is in keeping with national standards.

Regular home visits are made by the specialist nurse in order to give the parents and family on-going education, care and support.

If a child is diagnosed with sickle cell disease

If a child is diagnosed with sickle cell disease the child’s GP is advised to commence the baby on daily prophylactic Penicillin syrup by 3 months of age, as research has shown that children with sickle cell disease are unable to cope with infections caused by pneumococcal organisms, see Sickle Cell Disease.

In keeping with national recommendations the child’s parents are given a book entitled ‘Care and management of your child with sickle cell disease – a parent’s guide’, which gives them detailed information on how to look after their child, things to avoid to prevent complications and actions to take if the child becomes unwell. For more information about how to care for a child with sickle cell disease, see Resources for the General Public - A Parent’s Guide - Care and Management of Your Child with Sickle Cell Disease, and details of specialist services available in NW London hospital, see The Brent Sickle Cell & Thalassaemia Centre.

If a child is at risk or found to have Beta Thalassaemia Major

In NW London if a couple is known to be at-risk of having a child with beta Thalassaemia major the baby is offered retesting at six weeks old however most babies can be identified from the newborn sickle cell blood spot screening done at 5 – 8 days of age. But this test is not meant for identifying babies with Thalassaemia because the technique used in the laboratory may not identify Thalassaemia that is why it is important to retest all those known to be at-risk.

If the initial or retest result confirms that the child has beta Thalassaemia major the parents are given a book entitled ‘What is Thalassaemia?’ produced by the UK Thalassaemia Society, this gives a lot of information about Thalassaemia, treatments and how to look after a person with Thalassaemia major.

For further information

Contact the Brent Sickle Cell & Thalassaemia Centre or visit the NHS Sickle Cell and Thalassaemia (SCT) Screening Programme website.