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Glucose-6-phosphate dehydrogenase (G6PD)

Blood Sciences Test


EDTA Blood

Special Instructions


Factors affecting results

Blood transfusion within 4 months prior to testing can affect the results

Reticulocytes have a higher G6PD level than mature cells. Therefore it is not recommended that assays be performed after a severe haemolytic crisis, since G6PD levels may appear falsely elevated. Under these conditions, detection of deficiency may require family studies. Testing may be more helpful once retics have fallen to a normal level. If it is necessary to perform the assay with a raised retic count, a comment will be required explaining that the result may have been affected (false high)

Copper, which completely inhibits the enzyme at a concentration of 100 umol/L abd sulphate ions (0.005 mol/L) will decrease observed levels of G6PD activity. Certain drugs and other substances are also known to influence circulating G6PD.

Variable results may be obtained where the WBC is greatly increased or where the sample is extremely anaemic.

Reference Range

4.6 – 13.5 (U/g Hb)

From: G6PD Kit -Trinity Biotech

Test Usage

To aid in the diagnosis of G6PD deficiency

Turnaround time

14 days


Referral test – sent to Torbay

 Clinical Advice

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

Specimen Labelling Procedure
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