Lab Test

Alpha 1 Antitrypsin

Antrim #30050, EPIC: LAB5196, SOFT: A1AT

Specimen Collection Criteria

Collect: One Gold-top SST tube.

Physician Office/Drawsite Specimen Preparation

Let specimen clot 30-60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2–8°C or 36–46°F) the centrifuged collection tube within twelve hours of collection.

Preparation for Courier Transport

Transport: Centrifuged collection tube, refrigerated (2–8 °C or 36–46 °F). (Min: 0.5 mL)

Rejection Criteria

  • Grossly lipemic specimens.
  • Hemolyzed specimens.
  • Plasma specimens.


Centrifuged SST tubes may be transported and stored at ambient temperatures (2o to 30o C; 36o to 86o F) for up to 48 hours. DO NOT FREEZE TUBES CONTAINING BLOOD. For longer storage, the serum should be removed from the gel and refrigerated (2o -8o C) or frozen at -20o C or below.

Red-top tubes and Microtainers® may be stored at ambient temperatures for up to 16 hours and for up to 3 days at refrigerator temperatures (2o - 8o C). DO NOT FREEZE TUBES CONTAINING BLOOD. For longer storage, the serum should be removed from the clot and refrigerated (2o -8o C) or frozen at -20o C or below.

Serum specimens (pour-overs) may be stored at room temperature (20o to 26o C; 68o to 79o F) for up to 1 week, refrigerator temperature (2o to 8o C; 36o to 47o F) for two weeks, and at -20o C (-4o F) for up to 3 months. Specimens stored at -70o C (-94o F) can be stored indefinitely.


Sunday – Saturday, 24 hours a day.
Results available within 24 hours.

Reference Range

100-240 mg/dL.

Test Methodology



Alpha-1-antitrypsin, a serine protease, is one of the major inhibitors of proteolytic enzymes found in human plasma. Increased concentrations of alpha-1-antitrypsin are found in inflammatory or conditions in which other acute phase reactants are also increased. The level begins to increase after 1 day and peaks at 3-4 days. Decreased levels of alpha-1-antitrypsin may be associated with chronic obstructive pulmonary disease and liver disease (particularly in infants).

NOTE: Because AAT is increased in the presence of acute inflammation, interpretation should be made with caution if a deficiency is being considered. A normal C Reactive Protein (CRP) level can be useful to exclude acute inflammation.

Clinical Utility

More than 70 genetic variants of alpha-1-antitrypsin (AAT) have been described. Not all of these are associated with decreased AAT levels or with clinical disease. An individual homozygous for PiZ has about 15% normal AAT and Pi null has no AAT. Such individuals are at significantly increased risk for development of pulmonary emphysema at an earlier age than individuals with a normal AAT phenotype; this process is accelerated by smoking. Development of liver disease may occur in infants (hepatitis and cirrhosis) and in older individuals (chronic hepatitis and cirrhosis). In individuals with a decreased level of AAT, Alpha 1 Antitrypsin Phenotyping is recommended.

CPT Code


Test Codes

Antrim #30050, EPIC: LAB5196, SOFT: A1AT

Last Updated


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This directory currently reflects information only for specimens collected and/or processed at the
Farmington Hills, Grosse Pointe, Royal Oak, and Troy campuses.