RBC Enzyme Evaluation
Label Mnemonic: RBCZYME
Epic Lab Code: LAB4489
Downtime Form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Commercial Mail-out Laboratory
5231 RCP
Whole Blood
Collection Medium:
and or
Yellow top 6 mL (ACD solution B) Yellow top 6 mL (ACD solution B) Yellow top peds 2.7 mL (ACD solution B)
ACD-B tube is the only acceptable tube type at reference lab; MUST CALL Mailouts at 356-8593 for tube. This tube is not available through Hospital Stores.

Preferred Minimum: 12 mL whole blood (requires TWO 6 mL ACD-B tubes)
Absolute Minimum: 5 mL whole blood (requires TWO peds 2.7 mL ACD-B tubes)
Rejection Criteria:
Specimens other than Whole blood
Anticoagulants other than ACD
Delivery Instructions:
Deliver to laboratory immediately after collection.
Testing Schedule:
Monday through Friday; Varies
Turn Around Time:
2-10 days upon receipt at reference laboratory
Reference Range:
Definitive results and an interpretive report will be provided.
Interpretive Data:
A hematopathologist expert in these disorders evaluates the case, appropriate tests are performed, and an interpretive report is issued.
All enzyme defects, including erythrocyte enzyme errors, are inherited; some are sex-linked and located on the X chromosome. Some family members have no hematologic abnormalities, while others have a hemolytic anemia. For a number of red blood cell enzyme defects (e.g., deficiencies of hexokinase, glucose phosphate isomerase, pyruvate kinase), the sole clinical manifestation is hemolytic anemia. Glucose- 6-phosphate dehydrogenase deficiency is the most common metabolic error of the red cell and presents with acute hemolytic anemia in response to oxidant stress (e.g., drugs, acute infections, fava bean ingestion).

This is a consultative evaluation looking at red cell enzyme defects as the cause for early red cell destruction.

Useful for: Identifying defects of red cell enzyme metabolism and evaluating patients with hemolytic anemia.

Testing Algorithm
This is a consultative evaluation in which the case will be evaluated at the reference laboratory, the appropriate tests performed at an additional charge, and the results interpreted.

Glutathione and Reflexed RBC Enzymes are reflexed (added by reference laboratory) if original enzyme information is normal. Reflexed RBC Enzymes includes: adenosine deaminase, adenylate kinase, phosphofructokinase, phosphoglycerate kinase, triosephosphate isomerase, and pyrimidine 5'nucleotidase.
Kinetic Spectrophotometry (KS)
CPT Code:
82657-RBC enzymes
84087-Glucose phosphate isomerase
84220-Pyruvate kinase
82978-Glutathione (if appropriate)
See Additional Information:
Specimens Requiring Immediate Delivery