Cholinesterase, RBC and Plasma
Test Code
Clinical Significance
Cholinesterase, RBC and Plasma - True cholinesterase (RBC and plasma) activity is decreased in individuals with exposure to organophosphorous insecticides. True cholinesterase, found in erythrocytes and nerve tissue, is responsible for inactivating acetylcholinesterase at nerve endings. With decreased enzyme activity, patients may display a range of nervous system dysfunction. Analysis of RBC and serum or plasma activity is useful in monitoring exposure and recovery.
Test Resources
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Test Details
Methodology
This test code is for non-California patient testing. For California patient testing, use test code 90372.
Reference Range(s)
| Cholinesterase, RBC | 9572-15031 IU/L |
| Cholinesterase, Plasma | |
| Male | 3334-7031 IU/L |
| Female | 2504-6297 IU/L |
Alternative Name(s)
Preferred Specimen(s)
5 mL whole blood collected in an EDTA (lavender-top) and
1 mL plasma collected in an EDTA (lavender-top)
Minimum Volume
4 mL whole blood • 0.5 mL plasma
Collection Instructions
Draw two EDTA (lavender-top) tubes of whole blood. Spin one tube to separate plasma. Pour plasma into plastic aliquot tube (label this vial as plasma).
Send one 5 mL refrigerated uncentrifuged whole blood (4 mL minimum) and 1 mL refrigerated plasma (0.5 mL minimum).
Do not send packed cells. Do not send only one tube of whole blood.
Plasma cholinesterase results, as well as the calculated RBC cholinesterase results, are not accurate if plasma sample is not separated from the RBC's in a timely manner.
Hemolyzed plasma samples are not acceptable. Hemolysis can lead to apparent increases in plasma cholinesterase activity, and could mask an enzyme deficiency.
Transport Container
EDTA (lavender-top) tube and transport tube
Transport Temperature
Refrigerated (cold packs)
Specimen Stability
- Room temperature: 24 hours
- Refrigerated: 7 days
- Frozen: Unacceptable
Reject Criteria
Hemolysis • Lipemia • Received room temperature • Receipt of only a single tube of whole blood
Setup Schedule
1 mL plasma collected in an EDTA (lavender-top)
Send one 5 mL refrigerated uncentrifuged whole blood (4 mL minimum) and 1 mL refrigerated plasma (0.5 mL minimum).
Do not send packed cells. Do not send only one tube of whole blood.
Plasma cholinesterase results, as well as the calculated RBC cholinesterase results, are not accurate if plasma sample is not separated from the RBC's in a timely manner.
Hemolyzed plasma samples are not acceptable. Hemolysis can lead to apparent increases in plasma cholinesterase activity, and could mask an enzyme deficiency.
Refrigerated: 7 days
Frozen: Unacceptable