Cholinesterase, Plasma (CA Clients)

Test Code

90368

CPT Codes
82480

Preferred Specimen

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

Minimum Volume

0.5 mL

Other Acceptable Specimens

Plasma collected in: PPT potassium EDTA (white-top) tube

Instructions

Draw an EDTA (lavender-top) tube of whole blood. Spin tube to separate plasma. Pour plasma into plastic aliquot tube and refrigerate until shipping. 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 hr). Hemolysis can lead to apparent increases in plasma cholinesterase activity, and could mask an enzyme deficiency.

Note: PPT potassium EDTA (white-top) tubes should be centrifuged within 24 hours.

Transport Container

Transport tube

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. 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.

This test code is for California patient testing. For non-California testing, use test code 335.

Setup Schedule

Tues-sat

Report Available

2-5 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.

Reference Range

Male	3334-7031 IU/L
Female	2504-6297 IU/L

Clinical Significance

Approximately 1 in every 2500 individuals has inherited a defective enzyme or a deficiency of the enzyme (Pseudocholinesterase) that metabolizes succinylcholine (an anesthetic agent). With a "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 in patients with hepatic dysfunction.

Performing Laboratory

Quest Diagnostics Nichols Institute-San Juan Capistrano, CA

33608 Ortega Highway

San Juan Capistrano, CA 92675-2042

Last Updated: November 6, 2024

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.