• Diagnosis of thalassaemia:

• Haematological indices - reduction in haemoglobin level, size and volume ofred blood cell (Mean Corpuscular Haemoglobin - MCH and MeanCorpuscular Volume - MCV)

• A Family Origin Questionnaire: Sickle cell and thalassaemia screening: family

• origin questionnaire

• Blood film - microcytic and hypochromic red blood cells, anisocytosis,poikilocytosis

• Haemoglobin electrophoresis - detection of different proteins making uphaemoglobin molecule - HbA, HbA2, HbF

• Molecular methods - DNA analysis

  
  

The screening pathway

We have discussed how thalassaemia is passed on betweergenerations and why we should all be tested

Let's turn our attention now to the actual screening process and what is involved

In England, there is designated NHS Sickle Cell and Thalassaemia genetic screening programme (NHSSCTP) to identify people who are carriers for thalassaemia, sickle celldisease and other haemoglobin disorders. The screeningrogramme targets pregnant women, the biological father and new.born babies. It is important to note that anyone can be screened for thalassemia at any point of their lives, though carrier status is only detected during infancy from 7 months and above.

This test is covered by the NHS.

At the UKTS we believe in informed decision and stronglsupport being screened for thalassaemia before you think about having children so that you are able to make adecision that is best for you and your family.

Watch a short video about Screening tests for you and you babyNHS (youtube.com)

How does the screening pathway work for expectant parents?

If already pregnant

• At her irst appointment with the midwife,the pregnant woman wilbe asked to complete a Family Origin Questionnaire (FOQ).The aim of the FOQisto identify the population groups at highest risk of thalassaemia,sickle cell,and other haemoglobin variants.
  

• All women-whether they arein high or low prevalence areas-are offered screeningfor thalassaemia.The actual screening test for thalassaemia to find outifyou are a carrier,is a simple blood test takingjust a few minutes.The test should be offered to allpregnant women before they each 1o weks and6 days of pregnancy.It's really important the testis done early.The result of the blood test is back within a week.
  

• If the test esults show a positivethalassaemia carier result,the babys biologicalfather is ffered screning.It is important that the babys biologicalfather has a test to see if he is also a carrier as soon as possible.
  

• Babies can only inherithe condition if both parents are cariers.Ifests show the father is not acarier,the baby will ot have asevere form of halassemia and the mother will not be offered further tests in pregnancy.
  

However,it is important to note that thereis sila 50% chance that the baby could be acarrier.This is extremely important because when the baby is older,he or she could passon the unusua gene to his/her childen.It is therefore worth trying to find out if the baby is acarier early on in his or her life.Parents can discus the implcations of their baby being a carrier with their GP or a health care professional at their local sickle cell and thalassaemia centre. 

What happens if both parents are carriers?

If the blood test eveals the father is also a carre orthe biological fathe is absent or dedlines testing,parents wil be ofered pre-nata diagnosis PND)in the form of diagnosticteststo determineif their unbornchid wilave beta thalassaemia.As we have seen,when both parents ar cariers,thereisa in4(25%)chance that the baby could inherit the condition. 

A diagnostic test wil showifthe baby has thalassemia,is a carier or ifthe babyis completely unaffected.Tdeall,PND should be performed by12 weeks and 6 days of pregnancy.The PND method chosen wil depend on the gestational age of the foetus how many weeks of pregnancy have passed)and wllbe one of the following;

Further couseling and information are provided if the presence of thalassaemia is conftmed, includig advice and support for the options of continuaton or termination of pregnancy if thalassaemia major is identified.

Counselling and support

These are not easy choices or decisions to make, and it is unloubtedly a very stressful time for the parents.

Some parents decide not to conduct PND for a number of reasons. For example, it may go against their cultural beliefs, or they nlay not want to take the risk, albeit small, ofmiscarriage.

Support is available throughout the screening process. Ifthe mother is found to be a carrier of thalassaemia, she will beontacted by a specialist nurse or midwifemplications. If the blood tests reveal that both parents are carriers.hen they will be offered further counsellingcounsellor for genetic counselling to discuss the result and ointment with a health professional to getto help them through a very difficult time. If the result shows the baby has thalassaemia, the parents will be offered an aprinformation about thalassaemia and talk through their choies.

There is also support available from the charity Antenatal Rsults and Choices Antenatal Results & Choices.

Timing is critical Early acess to screening and PND an be critecal for couples at increased risk of having a child with thalasaemia. By having the test early, expectantparents can explore and understand al possible options and make informed decisions if their baby is at risk of being born with beta thalassaemia major.

The NHS New-born Blood Spot Screening Programme

The NHS ew-bom Blood Spot Screening Programme uses the he prck test - Where a tew drops ofbod are taken from the baby's heel when it is 5 days old-to test fo9 diferent healh conditions.of wich sickle cel disease is one. Br identifying any of these conditions early on.treatmet an be given promptly, Ahough thalassaemia isnot one of the conditions tested for in the Ne-bom Programme,if a baby has beta thalassaemia major, it wil be detected and reported as part of the proess.Howvever, theNew-born Screening Programme cannot identify carriers of thalassaemia until they are over approximately seven-twelve months in age.

The Natonal Congenital Anomaly and Rare Diseases Regstration (NCARDRS) and the Natonal Haemoglobinopathy kegistry are usualy informed once a diagosis 0t

thalassaemia is confirmed, unless the person opts out of registration.

Before conception

Pre-mplantation genetic diagnosis allows testing of eeas or embrvos from in-vitro fertlisaton technioues to alow implantation of disease-free embrys.

Sensityity is reuired as prenatal diagosis, pr-mnantation geneie daosis r teminaton f wregnans may mt he n kenig wih the rehgrs or amtburat helof the individual/coudle. Carefu and sensitive handlimg s also recured as the results from a screening tests may sometimes identif possible nor-datemnity of the baby.