Pyruvate kinase
PK deficiency is the most commonly encountered inherited defect of the Embden-Meyerhof pathway, with heterozygous frequencies that vary from 0.14 % in the US to 6 % in Saudi Arabia. PK deficiency is probably the most common single known cause of hereditary non-spherocytic haemolytic anaemia. It can be inherited in both an autosomal dominant and recessive fashion.
This disorder manifests clinically as a haemolytic anaemia, but symptoms may be less severe than the haematological indices indicate. The clinical severity of this disorder varies widely, ranging from a mildly compensated anaemia to severe anaemia of childhood. Neuro-developmental abnormalities should be interpreted with caution, as severe neonatal hyperbilirubinaemia, sufficient to cause kernicterus, has been described in deficiency of several red cell enzymes, including G6PD and PK. However, most affected individuals do not require treatment. In the most severe cases, death may occur in utero as a result of anaemia, or blood transfusions or splenectomy may be required, but most symptoms are limited to early life and to times of physiological stress or infection.
Haemolytic anaemia in newborns, infants and juveniles, often with history of jaundice, kernicterus and exchange transfusion
Variable presentation of anaemia, from mild to severe, often associated with growth delay or failure to thrive
Cholecystolithiasis (usually after the first decade of life but possibly in childhood)
More obvious symptoms during times of physiological stress including acute illness (particularly viral) and in pregnancy
6.2-14.2 U/g Hb
Special handling: samples received from outside Imperial College Hospital require an FBC and reticulocyte count result with a blood film and a control sample to monitor transport conditions.
Record last updated
August 27, 2025
Sample Container
4ml EDTA Vacutainers (Lavender top)
Sample Container
K2EDTA Paediatric Tube (Lavender top)
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Test Results
Yes, we have a Pathology User Guide
Yes. Please email your request to Imperial.nwlpcustomerservice@nhs.net
Results are communicated to clinical staff and are normally not communicated direct to patients either on telephone requests or in written report. If you need to contact us please click here to view the contact details page
Please contact the Customer Service Team Monday to Friday from 8:30am – 6:00pm on 0203 313 5353. Alternatively, see the Pathology User Guide for how to contact the relevant department. If advice is not urgent you can also email your query to Imperial.nwlpcustomerservice@nhs.net
Additional tests may be added by discussion with the relevant laboratory. The time limit for adding additional tests to a sample already received in the laboratory will depend on the type of sample and the department it was sent to.
Information on the repertoire of tests performed by pathology, including reference ranges, turnaround times and specimen requirements, can be found in the test directory.
Different tests have different sample stability requirements. If a comment on results indicates that the sample was delayed, the links below will indicate which tests may have been affected. This information is for serum or plasma samples.
For some tests, the impact of delay is consistent and these are marked with an arrow:
↑ indicates tests where delayed centrifugation results in falsely elevated results and the true level is likely lower than that reported.
↓ indicates tests where delayed centrifugation results in falsely lowered results and the true level is likely higher than that reported.
If there is no arrow, the true level may be lower or higher than reported.
Please interpret results with caution and consider the impact of any uncertainty.
The comment on the report will state how delayed the sample was. Please click the relevant link below to see which other tests may have been affected.
| >8h | >12h | >24h | >48h | >72h |
Phlebotomy services are not managed by NWLP. For further information please see:
Imperial College Healthcare Trust Phlebotomy services
Chelsea and Westminster Hospital NHS Foundation Trust Phlebotomy services
NWLP operates UKAS accredited medical laboratories as per the references below. The current scope of accreditation for all NWLP’s laboratories can be found on the UKAS website.
UKAS accredited medical laboratory/medical diagnostic service:
- Clinical Biochemistry No. 8673
- Haematology and Blood Transfusion No. 8674
- Infection & Immunity Sciences (Including Immunology, Virology, Microbiology and Histocompatibility and Immunogenetics ) No. 8659
- Cellular Pathology (Including Histopathology, Cytology and Molecular Pathology) No. 9615
If you require copies of our certificate of accreditation and associated documentation please contact Imperial.nwlpcustomerservice@nhs.net.
UKAS requires the laboratories to be accredited for a particular repertoire/scope (ISO15189), any changes or additions to repertoire require assessment by UKAS (extension to scope).
The BD Hospital Tube Guide, BD GP Tube Guide and BD Paediatric Tube Guide provide visual references to the correct tube types and collection instructions.
Home testing
INSTRUCTION SHEET FOR BLOOD SAMPLE COLLECTION
We also have two instruction videos available (one with subtitles and one without) – please click on the links to view the videos on Google.
Our accreditations
Upholding excellence in diagnostic standards
Our laboratories are accredited by the UK Accreditation Service (UKAS) against the international standard ISO15189:2022. UKAS is the accreditation body for the UK that assesses medical laboratories.
Find out more about our accreditations on the UKAS website.
UKAS website