Order Code TPIC Triosephosphate Isomerase 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
Evaluating individuals with chronic nonspherocytic hemolytic anemia
Evaluating individuals with early onset neurologic impairment
Genetic counseling for families with triosephosphate isomerase deficiency
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
Reporting Name
Triosephosphate Isomerase, BSpecimen Type
Whole Blood ACD-BSpecimen Minimum Volume
1 mL
Specimen Stability Information
Specimen Type | Temperature | Time |
---|---|---|
Whole Blood ACD-B | Refrigerated | 20 days |
Reject Due To
Gross hemolysis | Reject |
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 of age: 1033-1363 U/g Hb
Reference values have not been established for patients who are younger than 12 months of age.
Method Description
Triosephosphate isomerase interconverts glyceraldehyde 3-phosphate and dihydroxyacetone phosphate (DHAP). The rate of DHAP formation is measured by further converting it to alpha-glycerophosphate by alpha-glycerophosphate dehydrogenase which results in the oxidation of 1,4-dihydronicotinamide adenine dinucleotide (NADH) to NAD(+). The oxidation of NADH is measured spectrophotometrically by the decrease in absorbance at 340 nm on an automated chemistry analyzer. (Beutler E. Red Cell Metabolism. A Manual of Biochemical Methods. Grune and Stratton; 1984; 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)
Performing Laboratory

CPT Code Information
82657
Day(s) Performed
Weekly, Varies