Test Code PGKC Phosphoglycerate Kinase 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
Evaluation of individuals with Coombs-negative nonspherocytic hemolytic anemia, especially if X-linked inheritance pattern.
Evaluation of individuals with myopathic or neurologic symptoms
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
Phosphoglycerate Kinase, BSpecimen Type
Whole Blood ACD-BSpecimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood ACD-B | Refrigerated | 20 days |
Reject Due To
Gross hemolysis | Reject |
Clinical Information
Phosphoglycerate kinase (PGK) is an enzyme that converts 1,3-diphosphoglycerate to 3-phosphoglyceric acid) in one of the adenosine triphosphate (ATP) generating steps in glycolysis. PGK deficiency (OMIM 300653) is an X-linked disorder with a variable clinical phenotype. Manifestations include hemolytic anemia, myopathy/rhabdomyolysis, or neurologic impairment. Patients can have 1 or 2 systems affected but rarely have all 3. Clinical severity may not correlate with enzyme activity and female heterozygotes may possibly be mildly affected.
Reference Values
Only available as part of a profile. For more information see:
-HAEV1 / Hemolytic Anemia Evaluation
-EEEV1 / Red Blood Cell (RBC) Enzyme Evaluation
≥12 months: 142-232 U/g Hb
Reference values have not been established for patients who are younger than 12 months.
Interpretation
In phosphoglycerate kinase deficiency, red blood cell activity levels have been reported ranging from 1% to 49% of mean normal; however, affected patients more typically have values less than 20% of normal mean.(1)
Cautions
Recent transfusion may mask the patient’s intrinsic enzyme activity and cause unreliable results.
Method Description
Phosphoglycerate kinase (PGK) catalyzes the phosphorylation of adenosine diphosphate (ADP) to adenosine triphosphate (ATP) by conversion of 1,3-diphosphoglycerate (1,3-DPG) to 3,phosphoglyceric acid. In this assay, the reaction is driven in the reverse direction. The formation of 1,3-DPG is then measured through the glyceraldehyde phosphate dehydrogenase reaction as 1,3-DPG is converted to glyceraldehyde-3-phosphate resulting in the oxidation of 1,4-dihydronicotinamide adenine dinucleotide (NADH) to NAD(+). The decrease in absorbance, which occurs as NADH is oxidized, is measured spectrophotometrically at 340 nm on an automated chemistry analyzer.(Beutler E: Red Cell Metabolism. A Manual of Biochemical Methods. 3rd ed. Grune and Stratton; 1984:53-55; van Solinge WW, van Wijk: Enzymes of the red blood cell. In: Rifai N, Horvath AR, Wittwer CT: eds. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. Elsevier; 2018:chap 30)
Specimen Retention Time
7 daysPerforming 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 |
---|---|---|
PGKC | Phosphoglycerate Kinase, B | 44053-7 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
PGKCL | Phosphoglycerate Kinase, B | 44053-7 |
Day(s) Performed
Weekly