EDTA Blood
FBC and reticulocyte count must be performed and results sent with samples.
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.
5.2 – 11.5 (IU/g Hb)
From: G6PD Quantitative Assay, Synnovis
The G6PD assay is used to identify patients with Glucose-6-phosphate dehydrogenase deficiency; a hereditary enzyme disorder that causes varying degrees of haemolytic anaemia.
14 days
Referral test:
Samples from female patients sent to Synnovis laboratory (Kings) for quantitative assay.
Samples from male patients sent to NDDH Haematology laboratory for qualitative screen. Samples identified as G6PD deficient are sent to Synnovis (Kings) for quantitative assay.
Clinical advice is available from the Haematology Medical team (contact RD&E switchboard on 01392 411611)
Specimen Labelling Procedure
8210
