Alpha-1-Antitrypsin
Alternate name
Alpha 1 AT, A1AT
Specimen type
Blood
Bottle / container
4.9ml Serum Gel (Brown top)
Additional information
Measurement of alpha-1 antitrypsin is useful in the investigation of emphysema and unexplained liver disease in adults. In paediatric practice, alpha-1 antitrypsin deficiency may be associated with neonatal jaundice.
NOTE Inflammatory conditions may mask deficiency as AAT is an acute phase reactant. Increased levels also occur in malignancy, pregnancy and those taking exogenous oestrogens.
Deficiency leads to chronic obstructive airways disease, emphysema, neonatal/juvenile liver disease. Samples with an AAT concentration of 0.9g/L or below will undergo phenotypic analysis by isoelectric focusing to determine if the patient has one or more (heterozygosity or homozygosity) AAT deficiency alleles.
Users will be asked to contact the lab if alpha1-antitrypsin levels are borderline to clarify if phenotyping is required. Note, AAT levels may be within normal range in paediatric patients, therefore if there is a strong suspicion of AAT deficiency AAT phenotyping should also be performed.
Collection Conditions
Paediatric Alternative: 1.2ml Li Heparin (Orange top)
No special handling.
Transport to the laboratory
No special handling
Availability out of hours
Yes
Key factors that can affect test results
A1AT is a positive acute phase protein. High levels may also be seen in pregnancy and with oestrogen medications. Low levels may be of clinical importance in COPD, emphysema , asthma and liver disease. If a subnormal or low-normal concentration is found the sample is referred for phenotyping studies if these have not been done before.
Turnaround time
Routine: 24 Hours
Add on time limit
3 Days
Performed (by)
Mid Yorkshire Teaching NHS Trust
Category
Biochemistry