₁-Antitrypsin (₁-AT) is an ₁-globulin produced by the liver. Its function is inhibition of the proteolytic enzymes trypsin and plasmin, which are released by alveolar macrophages and by bacteria in the lungs. As with many other proteins, the ₁-AT molecule has several structural variants. Some of these variant molecules have different electrophoretic mobility and reduced ability to inhibit proteolytic enzymes.

Inherited deficiencies in normal ₁-AT activity are associated with the development, early in life, of lung and liver disorders in which functional tissue is destroyed and replaced with excessive connective tissue; that is, emphysema and cirrhosis may develop in children and young adults who are deficient in ₁-AT, without the usual predisposing factors associated with onset of these disorders. Such deficiencies are seen on serum protein electrophoresis as a flat area where the normal ₁-globulin hump should be. More detailed physiochemical analysis can demonstrate which variant form is present. Decreased levels of ₁-AT also are seen in nephrotic syndrome and malnutrition.

• 80 to 213 mg/dL

• Pregnancy
• Oral contraceptive and steroid administration
• Extreme physical stress caused by trauma or surgery

• Genetic absence or deficiency of ₁-AT, indicated by decreased levels of the protease
• Suspected inflammation, infection, and necrosis processes, indicated by increased levels of the protease
• Family history of ₁-AT deficiency

Nursing Care Before the Procedure

Client preparation is the same as that for any test involving collection of a peripheral blood sample (see Appendix I).

• The client should fast for 8 hours before the test.
• Water is not restricted.
• Oral contraceptives and steroids should be withheld 24 hours before the study, although this practice should be confirmed with the person ordering the test.

A venipuncture is performed and the sample collected in a red-topped tube. The sample should be handled gently to avoid hemolysis and frozen if not tested immediately.

Nursing Care After the Procedure

Care and assessment after the procedure are the same as for any study involving the collection of a peripheral blood sample.

• Resume meals or medications withheld before the test.
• Abnormal values: Note and report decreased levels. Assess for pulmonary or liver disorders and associated signs and symptoms, smoking history, and pollution in the home or work environment. Inform client of stop-smoking clinics and resources for genetic counseling. Instruct client in ways to protect pulmonary system from irritants. Inform client of the importance of medical follow-up. Suggest ongoing support resources to assist client in coping with illness and possible early death.