Test Library

Preferred Specimen(s): 1 mL serum

Minimum Volume: 0.5 mL

Collection Instructions: Centrifuge and transfer serum specimens to clean, plastic, screw-cap vial(s).

Specimen Container: Plastic screw-cap vial

Transport Temperature: Refrigerated (cold packs)

Specimen Stability:

  • Room temperature 21 days
  • Refrigerated 21 days
  • Frozen 30 days

Reject Criteria: Gross hemolysis

Methodology: Kinetic Spectrophotometric

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(s)

Male 3342-7586 IU/L
Female 2673-6592 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.