α1-Antitrypsin
Also known as: Acute Phase Proteins, Alpha1-Protease Inhibitor
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).
Special Instructions
Overnight fasting is preferred for patient preparation. If C-reactive protein (CRP) is positive, retest α1-antitrypsin levels in 10 to 14 days. Separate serum or plasma from cells after collection. Use when α1-globulin in serum protein electrophoresis is low, or two bands are seen in the α1-region.
Limitations
α1-antitrypsin levels may rise to normal in heterozygous deficient patients during concurrent infection, pregnancy, estrogen or steroid therapy, cancer, and postoperative periods. Homozygous deficient patients will not show such elevation. Normal levels may occur in patients with liver disease who are heterozygotes. Levels are typically low at birth but increase soon thereafter.
Methodology
Immunoassay
Biomarkers
LOINC Codes
- 1825-9
- 1825-9
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.3 mL
Container
Red-top tube, gel-barrier tube
Collection Instructions
Separate serum or plasma from cells.
Patient Preparation
Overnight fasting is preferred.
Storage Instructions
Maintain specimen at room temperature.
Causes for Rejection
Chylous serum
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 14 days |
| Refrigerated | 14 days |
| Frozen | 14 days |
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