Alpha-1-Antitrypsin Quantitation

Label Mnemonic:	A1AT
Epic code:	LAB927
Downtime form:	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 whole blood in light green top tube or ONE Microtainer^®

Testing Schedule:

24 hrs/day, 7 days a week, including holidays.

Turn Around Time:

1 hour (upon receipt in laboratory)

Reference Range:

90-200 mg/dL
A1AT is an acute phase reactant, therefore any inflammatory process may result in transient elevations of the patient's A-1-AT level.

Test Limitations:

Criterion: Recovery within plus or minus 10% of initial values.

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

Hemolysis: No significant interference up to an H index of 1000 
(approximate hemoglobin concentration: 1000 mg/dL).

Lipemia (Intralipid): No significant interference up to an L index of 
350 (approximate triglycerides concentration: 700 mg/dL). There is 
poor correlation between turbidity and triglycerides concentration.

Rheumatoid factors less than 100 IU/mL do not interfere.

No high dose hook effect is seen up to an alpha 1-antitrypsin 
concentration of 1200 mg/dL.

Elevated estrogen levels (oral contraceptives; third trimester of 
pregnancy) give rise to false positive results. CRP and haptoglobin 
should therefore also be determined.*

*Laurell CB, Kullander S, Thorell J. Effect of administration of a
 combined estrogen-progestin contraceptive on the level of individual
 plasma proteins. Scand J Lab Invest 1968;21:337-343.

Methodology:

Immunoturbidimetric

CPT Code:

82103