Laboratory Services

Alpha-1-Antitrypsin Phenotype, Serum

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Updated Test Information:

Test Description
Alpha-1-Antitrypsin Phenotype, Serum

A1A Phenotyping; a-1-Antitrypsin Phenotype; AAT Phenotyping; Alpha 1 Antitrypsin; Anti-Alpha-1-Trypsin; Antitrypsin; Antitrypsin PhenotypePi Typing (Alpha-1-Antitrypsin Phenotyping); Protease Inhibitor Allo Typing; Alpha-1-Antitrypsin Reflex

Test ID
General Information

Useful for identification of homozygous and heterozygous phenotypes of the alpha-1-antitrypsin deficiency

Specimen Type

Serum: (1.25 mL)

Specimen Requirements

  • Preferred: Red Top

  • Acceptable: Serum Gel

Minimum Sample Volume

0.5 mL


  • Refrigerated (preferred): 28 days

  • Ambient: 28 days

  • Frozen: 28 days

Unacceptable Specimen Conditions

Gross Lipemia


  • This assay identifies the phenotype of the circulating alpha-1-antitrypsin (A1A) protein. If the patient is already on replacement therapy, the phenotype will detect patient and replacement protein.                         

  • If 2 bands are seen, such as an M band and a Z bands, it is reported as MZ (eg, heterozygous) 

  • If 1 band is seen, such as the Z band and the quantitative level is consistent with a homozygote, the phenotype is assumed to be homozygous and is reported as ZZ.


  • A1AP2: Isoelectric Focusing

  • AATP: Nephelometry

Estimated TAT

2-6 days

Testing Schedule


Test Includes

  • Alpha-1-Antitrypsin, S

  • Alpha-1-Antitrypsin Phenotype

CPT Code(s)

82103, 82104

Reference Range


100 - 190 mg/dL


The interpretive report will identify the alleles present. For rare alleles, the report will indicate whether or not they have been associated with reduced quantitative levels of alpha-1-antitrypsin.

Performing Lab


LOINC Code(s)

6771-0, 32769-2

Additional Information