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Haemoglobinopathy Screen

Blood Sciences Test


EDTA blood

Factors affecting results

Blood transfusion in 4 months prior to screening can affect the results

Alpha thalassaemia is difficult to diagnose in the presence of iron deficiency anaemia

Samples must be tested within 24 hours of collection

Reference Ranges

HbF            0 – 2.0%

HbA2         1.5 – 3.5%

Test Usage

To screen for the presence of abnormal Haemoglobins.

See also Sickle Cell Screening

A low MCV and MCH may indicate a thalassaemia trait. Iron deficiency anaemia should be excluded in the first instance.

If a thalassaemia screen is required patient consent must be obtained for further testing to be performed.  HbF and HbA2 levels will be determined. Other abnormal haemoglobin variants (e.g. HbS, HbC, HbE, HbO) will be looked for. An interpretative comment will be provided.

PLEASE NOTE If a sickle screen is required urgently (e.g. pre-op), please make this clear on the request form, and by contacting the laboratory.

Screening for thalassaemia and abnormal haemoglobins in pregnancy is performed in accordance with national guidelines for a low prevalence area.

Turn around time

3 working days


In House

Confirmation of Hb variants is performed by Torbay Hospital

Clinical Advice

Clinical advice is available from the Haematology Medical team (contact RD&E switchboard on 01392 411611)

Where clinically indicated, specialist advice can be obtained at a combined Haematology-Genetic Counselling clinic.


Specimen Labelling Procedure
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