Glucose Phosphate Isomerase Enzyme Activity, Blood
Use
This test is useful for evaluating individuals with Coombs-negative chronic hemolysis as part of a profile. It measures the activity of the glucose phosphate isomerase (GPI) enzyme, which is crucial in the glycolysis pathway, converting glucose 6-phosphate to fructose 6-phosphate. GPI deficiency is linked to nonspherocytic hemolytic anemia, which can vary from mild to severe anemia and may include jaundice, gallstones, and splenomegaly. In some cases, it leads to neonatal death or hydrops fetalis. Rarely, it can also involve neurological defects and granulocyte dysfunction.
Special Instructions
This test is only orderable as part of a profile, such as the Hemolytic Anemia Evaluation, Blood (HAEV1) or the Red Blood Cell (RBC) Enzyme Evaluation, Blood (EEEV1).
Limitations
Recent transfusions may obscure intrinsic enzyme activity, leading to inaccurate results. Reticulocytosis can elevate activity levels, potentially masking GPI deficiency cases. Comparing to other red blood cell enzyme activity levels or accounting for reticulocytosis may be needed for accurate diagnosis.
New York Approved
Methodology
Automated Analyzer (Clinical Chemistry)
Biomarkers
LOINC Codes
- 44050-3
- 44050-3
Result Turnaround Time
5 days
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
Not provided
Minimum Volume
Not provided
Container
ACD-B
Causes for Rejection
Gross hemolysis; Fully clotted
Stability Requirements
| Temperature | Period |
|---|---|
| Refrigerated | 20 days |