Alpha-1-Antitrypsin (SERPINA1) Enzyme Concentration and 2 Mutations with Reflex to Alpha-1-Antitrypsin Phenotype
0051256
Ordering Recommendation
Diagnostic testing for alpha-1-antitrypsin deficiency or carrier screening for alpha-1-antitrypsin deficiency.
Mnemonic
A1A GENO
Methodology
Immunoturbidimetry/Polymerase Chain Reaction/Fluorescence Monitoring/Isoelectric Focusing
Performed
Mon, Thu
Reported
2-10 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
  
Collect
Serum separator tube AND lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).  
Specimen Preparation
Allow serum to clot completely at room temperature. Separate serum from cells ASAP or within 2 hours of collection. Transport 0.5 mL serum AND 3 mL whole blood. (Min: 0.5 mL serum AND 0.5 mL whole blood)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
  
Remarks
  
Stability
Serum: Ambient: 8 hours; Refrigerated: 5 days; Frozen: 2 weeks
Whole Blood:
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
 
 
Test Number Components Reference Interval
0050001Alpha-​1-​Antitrypsin 100-​200 mg/dL
 Alpha-​1-​Antitrypsin Phenotype By report
Interpretive Data
Background Information for A1A (SERPINA1) Enzyme Concentration and 2 Mutations with Reflex to A1A Phenotype:
Characteristics:
Coughing, wheezing, chronic obstructive pulmonary disease, emphysema, cirrhosis.
Incidence:
1 in 3000 to 1 in 5000.
Inheritance:
Autosomal recessive.
Cause:
Mutations in the AAT glycoprotein gene on chromosome 14q31-32.3; homozygosity for the Z allele is the most common cause.
Clinical Sensitivity:
95 percent.
Mutations Tested:
S allele (c.791A>T) and Z allele (c.1024G>A).
Methods:
Genotyping performed by PCR followed by fluorescent probe melting analysis; AAT protein concentration measured using immunoturbidmetric assay; phenotyping performed by isoelectric focusing. Genotyping and AAT serum protein concentration determination are performed on all specimens. Protein phenotyping is performed on specimens that have AAT serum concentrations of less than 100 mg/dL and are heterozygous for either the S or Z allele by genotyping. In addition, protein phenotyping is performed on specimens that have serum protein concentrations of less than 100 mg/dL and do not contain either S or Z alleles by genotyping. Isoelectric focusing is not performed on specimens that are homozygous for deficiency alleles (ZZ, SZ, or SS) by genotyping.
Analytical Sensitivity and Specificity:
99 percent.
Limitations:
Mutations other than those targeted in S allele (c.791A>T) and Z allele (c.1024G>A) will not be detected. Diagnostic errors can occur due to rare sequence variations.

This test is performed pursuant to an agreement with Roche Molecular Systems, Inc.





See Compliance Statement C: www.aruplab.com/CS
Statement C: The performance characteristics of this test were validated by ARUP Laboratories. The U.S. Food and Drug Administration (FDA) has not approved or cleared this test; however, FDA approval or clearance is currently not required for clinical use of this test. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions. ARUP is authorized under Clinical Laboratory Improvement Amendments (CLIA) and by all states to perform high-complexity testing.

Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
 
Note
Alpha-1-antitrypsin serum protein concentration determination and A1A genotyping are performed on all specimens. If two deficiency alleles (ZZ, SZ, or SS) are detected, then no further testing will be added. If the protein concentration is less than 100 mg/dL and only one or no deficiency allele is detected by A1A genotyping, then phenotyping will be added. Additional charges apply.
CPT Code(s)
82103, 81332; If reflexed, add 82104
Components
Component Test Code*Component Chart Name
0050001Alpha-1-Antitrypsin
0051259Alpha-1-Antitrypsin S Allele
0051260Alpha-1-Antitrypsin Z Allele
0051261Alpha-1-Antitrypsin SZ Interpretation
0089005Alpha-1-Antitrypsin Phenotype
2001289Alpha-1-Antitrypsin SZ Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • A-1-Antitrypsin
  • A1A
  • AAT
  • Alpha 1 Antitrypsin
  • Alpha 1 Antitrypsin Genotype
  • Alpha one Antitrypsin
  • Alpha1-Proteinase Inhibitor
  • Anti-Alpha-1-Trypsin
  • Antitrypsin
  • Phenotype
  • Phenotyping
  • Pi Typing
  • Prolastin
  • Protease I