Test Code HKC Hexokinase Enzyme Activity, Blood
Specimen Required
Only available as part of a profile. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation, Blood
-EEEV1 / Red Blood Cell (RBC) Enzyme Evaluation, Blood
Useful For
The evaluation of individuals with Coombs-negative chronic hemolysis
Method Name
Only available as part of a profile. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation, Blood
-EEEV1 / Red Blood Cell (RBC) Enzyme Evaluation, Blood
Kinetic Spectrophotometry (KS)
Reporting Name
Hexokinase, BSpecimen Type
Whole Blood ACD-BSpecimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood ACD-B | Refrigerated | 20 days |
Reference Values
Only available as part of a profile. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation, Blood
-EEEV1 / Red Blood Cell (RBC) Enzyme Evaluation, Blood
≥12 months: 0.7-1.7 U/g Hb
Reference values have not been established for patients who are younger than 12 months.
Interpretation
Clinical correlation or genetic confirmation may be required to establish hexokinase (HK) deficiency as a cause of hemolytic anemia as the assayed activity level in confirmed cases can vary from markedly decreased to borderline normal levels due to a compensated increase in enzyme by reticulocytes. Comparison of HK activity levels to other red blood cell enzyme activity can be very useful. Heterozygous individuals have moderately decreased to low normal HK levels and are expected to be clinically unaffected.
Increased HK activity may be seen when reticulocytes are increased and is not supportive of a diagnosis of HK deficiency.
Clinical Reference
1. Koralkova P, Mojzikova R, van Oirschot B, et al: Molecular characterization of six new cases of red blood cell hexokinase deficiency yields four novel mutations in HK1. Blood Cells Mol Dis. 2016 Jul;59:71-76
2. Koralkova P, van Solinge WW, van Wijk R: Rare hereditary red blood cell enzymopathies associated with hemolytic anemia-pathophysiology, clinical aspects and laboratory diagnosis. Int J Lab Hematol. 2014;36:388-397
Performing Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
82657
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
HKC | Hexokinase, B | 49216-5 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
HKCL | Hexokinase, B | 49216-5 |
Day(s) Performed
Weekly