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