Test Overview
Test Methodology

Photometric, Acetylthiocholine Substrate

Test Usage

Monitoring for exposure to organophosphorus insecticides. Monitoring patients with liver disease, particularly those undergoing liver transplantation. Identifying those patients with an atypical gene who have low levels of cholinesterase which is not inhibited by dibucaine. These individuals are sensitive to the muscle relaxant succinylcholine since they are unable to hydrolyze it rapidly.

Reference Range *

Reference values have not been established for patients that are less than 18 years of age. Males: >or=18 yrs: 3,100 - 6,500 U/L; Females: 18-49 yrs: 1,800 - 6,600 U/L; >or=50 yrs: 2,550 - 6,800 U/L.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details
Days Set Up
Monday - Friday
Analytic Time

2 - 5 days

Soft Order Code
MiChart Code
Pseudocholinesterase (PCHE) Total (Sendout)
  • Insecticide poisoning
  • Nerve gas poisoning
  • Cholinesterase
  • PCHE
Reference Laboratory
Mayo PCHE1
Special Testing
Specimen Requirements
Collection Instructions

Collect specimen in a red top or SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate. For cases of prolonged apnea following surgery, wait 24 hours before obtaining specimen. SST tube must be spun within 2 hours of collection.

Normal Volume
1 mL serum
Minimum Volume
0.25 mL serum
Storage Temperature
Refrigerated preferred, frozen acceptable
Additional Information

Test sent to Mayo Medical Laboratories.

CPT Code
Fee Code