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Test Directory -  Haemoglobinopathy Screen

Synonyms

Thalassaemia screen, Sickle screen, Haemoglobin electrophoresis, Haemoglobin variant, Hb variant.

Clinical Indications

To confirm or exclude presence of variant haemoglobins and or beta thalassaemia. Part of national screening programme of all antenatal patients for early detection of haemoglobin abnormalities including sickle cell and thalassaemia conditions.

Test Includes

HPLC (High Performance Liquid Chromatography) & FBC. If applicable confirmatory tests or sent to referral laboratory for confirmation.

Request Form

Combined Pathology Blood form (Yellow/Black or Blue for GP's)
Antenatal samples should use an Antenatal booking form with a completed family origin questionnaire.

Availability

On request; daily routine working day. If urgent please contact laboratory.

Specific Criteria

Ethnic origin required. Family origin questionnaire (FOQ) required if pregnant.

Turnaround Time

Within 3 days unless confirmatory testing is required.

Specimen

Whole blood (EDTA)

Volume

3 mL.

Container

Purple top (EDTA) tube.

Lab. Handling

Hb variants requiring confirmation sent to Royal London Hospital. Variants requiring definitive diagnosis sent to Royal London and St Barts Hospital. Contact lab first if DNA / globin synthesis is required.

Causes for Rejection

Unlabelled sample. Previously reported Haemoglobinopathy screen. Underfilled or clotted samples. Samples of Infants of less than 6 months of age are not tested here, they are referred to the Central Middlesex Hospital if confirmation of blood spot screen is required.,

Limitations

Recent transfusion may mask / reduce level of any variants present.

Reference Range

Hb F <2.0 adult , <4.0 at 12 months
Hb A2 1.5 - 3.4

Interpretation

See Information Leaflets available

        

 

Version 1.0 / January 2013

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