Cholinesterase, Plasma

Test Code

335

CPT Codes
82480<br /> **This test is not available for California patient testing. For California patient testing, use test code 90368**

Preferred Specimen

1 mL plasma collected in an EDTA (lavender-top) tube

Minimum Volume

0.5 mL

Instructions

Draw an EDTA (lavender-top) tube of whole blood. Spin tube to separate plasma. Pour plasma into plastic aliquot tube and refrigerated until shipping. Ship plasma sample refrigerated. Do not send packed cells. Do not send one tube of whole blood.
Plasma cholinesterase results are not accurate if plasma sample is not separated from RBCs in a timely manner (within 1 hour). Hemolyzed plasma can lead to apparent increases in plasma cholinesterase activity, and could mask an enzyme deficiency.

Transport Temperature

Refrigerated (cold packs)

Specimen Stability

Room temperature: 21 days
Refrigerated: 21 days
Frozen: 30 days

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Hemolysis

Methodology
Kinetic Spectrophotometric (KS)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics Nichols Institute. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

A.M. Sets up 5 days a week.

Report Available

Reports in 2 days.

Limitations

Results may be depressed in patients who consume oral contraceptives. Hepatic disease may cause up to a 70% decrease in enzyme levels. Cholinesterase may be slightly elevated in patients with obesity or diabetes.

Clinical Significance

Approximately 1 in every 2500 individuals has inherited defective or deficiency of the enzyme (pseudocholinesterase) that metabolizes succinylcholine (an anesthetic agent). With "normal" dosage, these individuals have prolonged apnea. Such individuals are responsive at much smaller concentrations of this anesthetic agent than the general population. Low concentrations of pseudocholinesterase are observed in individuals exposed to organophosphorous insecticides and patients with hepatic dysfunction.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.