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Order Code TPI1 Triosephosphate Isomerase Enzyme Activity, Blood


Specimen Required


Container/Tube:

Preferred: Yellow top (ACD solution B)

Acceptable: Lavender top (EDTA)

Specimen Volume: 6 mL

Collection Instructions: Send in original tube. Do not transfer blood to other containers.


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

Kinetic Spectrophotometry (KS)

Reporting Name

Triosephosphate Isomerase, B

Specimen Type

Whole Blood ACD-B

Specimen 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

≥12 months: 1033-1363 U/g Hb

Reference values have not been established for patients who are less than12 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 of1,4-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. 3rd ed. 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

Mayo Clinic Laboratories in Rochester

CPT Code Information

82657

Day(s) Performed

Tuesday, Thursday

Forms

If not ordering electronically, complete, print, and send a Benign Hematology Test Request (T755) with the specimen.