Accessibility

Our global life sciences company brings diagnostic testing & drug development together.

α1-Antitrypsin

CPT: 82103
Print Share

Synonyms

  • Acute Phase Proteins
  • Alpha1-Protease Inhibitor

Expected Turnaround Time

1 - 2 days


Related Documents

For more information, please view the literature below.

α1-Antitrypsin Deficiency


Specimen Requirements


Specimen

Serum (preferred) or plasma


Volume

1 mL


Minimum Volume

0.3 mL (Note: This volume does not allow for repeat testing.)


Container

Red-top tube, gel-barrier tube, lavender-top (EDTA) tube, or green-top (heparin) tube


Collection

Separate serum or plasma from cells.


Storage Instructions

Maintain specimen at room temperature.


Stability Requirements

Temperature

Period

Room temperature

14 days

Refrigerated

14 days

Frozen

14 days

Freeze/thaw cycles

Stable x3


Patient Preparation

Overnight fasting is preferred.


Causes for Rejection

Chylous serum


Test Details


Use

Detection of hereditary decreases in the production of α1-antitrypsin (α1AT). Decreased or nearly absent levels of α1AT can be a factor in chronic obstructive lung disease and liver disease. An increased prevalence of non-MM phenotypes is found with cryptogenic cirrhosis and with CAH. Cirrhosis in a child should raise consideration of α1AT deficiency or Wilson's disease. Diagnosis of inflammatory states, if elevated (eg, rheumatoid arthritis, bacterial infection, vasculitis, neoplasia).


Limitations

α1AT may be elevated into normal range in heterozygous deficient patients during concurrent infection, pregnancy, estrogen therapy, steroid therapy, cancer, and during postoperative periods. Homozygous deficient patients will not show such elevation. Normal α1AT levels may occur in patients with liver disease who are heterozygotes. In normals, pregnancy and contraceptive medication may elevate levels. Levels are normally low at birth but rise soon thereafter.


Methodology

Immunologic


Contraindications

If CRP is positive, retest α1AT in 10 to 14 days.

Reference Interval

See table.

Age

Male

mg/dL

Female

mg/dL

0 to 7 d

102–186

102–186

8 to 30 d

73–187

73–187

31 d to 5 y

86–173

86–173

6 to 12 y

99–156

99–156

13 to 40 y

95–164

100–188

>40 y

101–187

101–187


Additional Information

Should be run when α1-globulin in serum protein electrophoresis is low or when two bands are seen in the α1-region. Heterozygous patients exhibit AAT levels which are commonly about 60% of normal. Homozygous recessive α1AT patients exhibit levels at about 10% of normal. Phenotyping is desirable on patients with low values and on all patients being worked up for AAT-deficient liver disease. Most pathologic is homozygous state ZZ. An M null genotype will have phenotype as MM but low serum level. AAT is one of the alpha-globulins, which together are called “acute phase reactants.” These rise rapidly, but nonspecifically, in response to inflammatory insults.


LOINC® Map

Order Code Order Code Name Order Loinc Result Code Result Code Name UofM Result LOINC
001982 Alpha-1-Antitrypsin, Serum 1825-9 001982 Alpha-1-Antitrypsin, Serum mg/dL 1825-9

For Providers

Please login to order a test

Order a Test

© 2021 Laboratory Corporation of America® Holdings and Lexi-Comp Inc. All Rights Reserved.

CPT Statement/Profile Statement

The LOINC® codes are copyright © 1994-2021, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee. Permission is granted in perpetuity, without payment of license fees or royalties, to use, copy, or distribute the LOINC® codes for any commercial or non-commercial purpose, subject to the terms under the license agreement found at https://loinc.org/license/. Additional information regarding LOINC® codes can be found at LOINC.org, including the LOINC Manual, which can be downloaded at LOINC.org/downloads/files/LOINCManual.pdf