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Test Directory -  G6PD Screen


G6PD, G6PD deficiency screen.

Clinical Indications

Some cases of neonatal jaundice and anaemia. Occasional cases of anaemia. Haemolysis when patient exposed to oxidant compounds.

Request Form

Combined Pathology Blood form (Yellow/Black or Blue for GP's)


On request after discussion with a Consultant Haematologist

Specific Criteria

To be discussed with Consultant Haematologist

Turnaround Time

72 hours unless clinical need requires urgent testing


Whole blood (EDTA)


3ml. Paediatric samples accepted by arrangement with laboratory.


Purple top (EDTA) tube

Lab. Handling

Where the screen indicates a G6PD deficiency the sample is referred to The Royal London & St Barts London for quantitative assay. Send by first class post or taxi.

Causes for Rejection

Unlabelled or incorrectly labelled or insufficient patient identifiers sample. Not meeting specific criteria for analysis. Delay in sample reaching laboratory.  Insufficient sample volume. Poor sample quality due to deterioration, haemolysis, presence of clot.


White blood cells, platelets and reticulocytes may be rich in G6PDH and may, if present at increased levels give a false normal result.

Reference Range

Where a screen indicates G6PD deficiency the sample is referred for quantative assay (if sufficient sample).
Samples on children <6 months age, or individuals with a raised reticulocyte, platelet or white cell count , may be falsely normal. A Repeat sample may be requested after a haemolytic episode to confirm G6PD status.



Version 1.0 / January 2013