Joanne Mallon, Nora O Neill, Dr D Hull Antenatal midwife coordinator, Consultant Haematologist

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1 Title: CLINICAL GUIDELINES ID TAG Guideline for Antenatal Screening for Haemoglobinopathies Author: Designation: Speciality / Division: Directorate: Joanne Mallon, Nora O Neill, Dr D Hull Antenatal midwife coordinator, Consultant Haematologist Obstetrics-IMWH Acute Services Date Uploaded: 5 th January 2015 Consulted upon: Authorised by Yes Mr David Sim Ms Patricia McStay Approved by: (Name of AMD) Applicable to: (delete Yes / No as appropriate) Review Date (Every 2 years or sooner if required): Clinical Guideline ID: Dr Martina Hogan Dept./Division Only: YES-IMWH Directorate Only: NO Trust-wide: NO 1 st November 2017 CG0082

2 Guideline for Antenatal Screening for Haemoglobinopathies Purpose To provide guidance to all medical and midwifery staff in the Southern Health and Social Care Trust (SHSCT) on Antenatal Screening for Haemoglobinopathies. Objectives To inform staff of the availability of screening for Haemoglobinopathies within the SHSCT To advise staff who to offer screening to To provide staff with information on interpreting the results of the tests Roles and Responsibilities All Midwifery and Medical staff providing care must adhere to these guideline. Introduction Haemoglobin is a substance in red blood cells which binds to oxygen. This allows oxygen to be transported via the circulatory system around the body to be released into body tissue that requires it. Sickle Cell disease and Thalassaemia are the two most common haemoglobin disorders found in the UK Sickle Cell Sickle cell disease is a hereditary blood disorder characterized by red blood cells which have an abnormal, rigid, sickle shape. This sickling decreases the cells flexibility and results in a risk of various complications e.g. pain, stroke, low immunity to infection, lung problems and chronic disorders of the hips and kidneys. In the most common type of sickle cell disease in the UK the abnormal globin chain is known as sickle haemoglobin (Hb-S). A person inheriting one sickle cell gene is known as a carrier without the disease (or has a sickle cell trait ) while someone who inherits a copy of the sickle cell gene from both parents has sickle cell disease

3 Thalassaemia There are two common types of thalassaemia: alpha-thalassaemia in which too few alpha chains are produced and beta-thalassaemia in which too few beta chains are produced. In thalassaemia the disease is caused by the weakening and destruction of red blood cells. Thalassaemia is caused by variant or missing genes that affect how the body makes haemoglobin. People with thalassaemia make less haemoglobin and fewer circulating red blood cells than normal, which results in mild or severe anaemia. Thalassaemia can cause significant complications such as iron overload, bone deformities, cardiovascular illness and infection Screening The National Screening Committee (NSC) recommends screening antenatal screening for haemoglobinopathies. The type of screening should depend on the prevalence of the condition in the area. In an area identified as high prevalence for sickle cell disease or thalassaemia (fetal prevalence of sickle cell disorder greater than 1.5 per 10,000 pregnancies) screening is advised for all pregnant woman to identify carriers of sickle cell and/or thalassaemia, using laboratory testing by high performance liquid chromatography (HPLC) and the Family Origin Questionnaire (FOQ) Appendix 1 Where prevalence of sickle cell disease is low (fetal prevalence lower than 1.5 cases per 10,000 pregnancies) screening is based on assessing the individual risk by determining the family origin of the woman and that of the baby s father the using the Family Origin Questionnaire (FOQ) as well as a formal process of inspection of routine blood indices for thalassaemia. Northern Ireland is a Low Prevalence area for haemoglobinopathies. The offer to screen at booking Assess the individual risk to screen by determining the country of origin of the mother and the baby s father using the FOQ as a guide. Information about screening for sickle cell disease and thalassaemia which should include carrier status and its implications should be given to women at first contact

4 with a healthcare professional if the individual risk assessment deems the woman to be at high risk All women should have a Full Blood Count (FBC) tested at booking. The results of the FBC must include a review of the normal red cell indices to assess the need to screen for Thalassaemia i.e. a low Mean Corpuscular Volume (MCV) / a low Mean Corpuscular Haemoglobin (MCH) Appendix 1 Offer to screen for Sickle Cell Disease and Thalassaemia if individual assessment or FBC review indicate the need for same. Offer to screen if there is a family history of Sickle Cell Disease of Thalassaemia. Sickle cell can be screened for on the booking FBC sample by requesting this to be tested on the SHSCT Clinical Chemistry request form. The sample should be sent to local laboratory for testing by Craigavon Area Hospital Laboratory. For Thalassaemia screening take 5 ml purple topped EDTA sample and request Thalassaemia screening on SHSCT Clinical Chemistry request form. This sample should be sent to local laboratory for testing in Belfast City Hospital. Results If a significant haemoglobin variant is detected, the baby s father should be offered screening immediately if not already done The couple should be offered counselling and the pregnancy managed as per the RCOG guidelines for the management of Sickle Cell Disease and Thalassaemia in pregnancy References 1. Nice Guidelines: Antenatal Care, routine care for the healthy pregnant woman. March Screening for haematological problems: 2. National Screening Committee: 3. Royal College of Obstetricians and Gynaecologists (RCOG): Green Top Guideline 61 July 2011: Management of Sickle Cell Disease on Pregnancy Blackwell Publishing Ltd: British Journal of Haematology (BJH): Significant haemoglobinopathies:guidelines for screening and diagnosis,149, Joanne Mallon & Nora O Neill with advice from Dr D Hull 2014

5 Appendix 1 Review of FBC red cell indices at booking: IF Hb < 110g/l MCV < 80fL check Iron studies i.e. Ferritin, B12, Folate MHC < 27 pg If the Ferritin level is normal and the MCV and MCH remain low bring to the attention of consultant re need to screen for Haemoglobinopathies

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