Aspartate Aminotransferase (AST)
Label Mnemonic: AST
Epic code: LAB131
Downtime form: A-1a Doctor/Provider Orders - Pathology Core and Specialty Care Nursery
Chemistry
6240 RCP
356-3527
Specimen(s):
Plasma
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3 mL light green top tube or 1 light green top Microtainer® for pediatric patients
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
1 hour (upon receipt in laboratory)
Reference Range:
Males; 0-40 U/L
Females; 0-32 U/L

Pediatric Ranges:
Age               Male/Female U/L
1-3 years              10-50
4-6 years              10-45
7-12 years             10-40
13-18 years            10-35
Comments:
Avoid hemolysis. Adult reference ranges changed 11/26/2013.

This test is also performed in the Iowa River Landing (IRL) clinical laboratory (for specimens drawn at that site).
Test Limitations:
Criterion: Recovery within plus or minus 10% of initial value.

Hemolysis interferes due to AST activity from erythrocytes (index of 
50).

Icterus: No significant interference up to an I index of 60 
(approximate conjugated and unconjugated bilirubin concentration: 60 
mg/dL).

Lipemia (Intralipid): No significant interference up to an L index of 
250 (approximate triglycerides concentration: 500 mg/dL). There is 
poor correlation between turbidity and triglycerides concentration. 
Lipemia may cause absorbance flagging as a result of an absorbance 
increase.

Reference
Glick MR, Ryder KW, Jackson SA. Graphical Comparisons of Interferences 
in Clinical Chemistry Instrumentation. Clin Chem 1986;32:470-474.
Methodology:
Spectrophotometric
CPT Code:
84450
 
See also:
Aspartate Aminotransferase-Other, Body Fluid