Sorted By Test Name - Mayo Medical Laboratories

A1AF
182
AAT
8161
Most normal individuals have the M phenotype (M, M1, or M2). Over 99% of M phenotypes are
genotypically MM. In the absence of family studies, the phenotype (M) and quantitative level can be used
to infer the genotype (MM). The most common alleles associated with a quantitative deficiency are Z and
S. The reports for the rare alleles will indicate whether or not they have been associated with reduced
quantitative levels.
Clinical References: Morse JO: Alpha-1-antitrypsin deficiency. N Engl J Med 1978;299:1045-1048;
1099-1105.
Alpha-1-Antitrypsin, Random, Feces
Clinical Information: Alpha-1-antitrypsin (A1A) is resistant to degradation by digestive enzymes
and is, therefore, used as an endogenous marker for the presence of blood proteins in the intestinal tract.
A1A clearance is reliable for measuring protein loss distal to the pylorus. Gastrointestinal protein
enteropathy has been associated with regional enteritis, sprue, Whipple's intestinal lipodystrophy, gastric
carcinoma, allergic gastroenteropathy, intestinal lymphangiectasia, constrictive pericarditis, congenital
hypogammaglobulinemia, and iron deficiency anemia associated with intolerance to cow's milk.
Useful For: Diagnosing protein-losing enteropathies, especially when used in conjunction with serum
alpha-1-antitrypsin (A1A) levels as a part of A1A clearance studies (see #8835 "Alpha-1-Antitrypsin
Clearance, Feces and Serum"; preferred test)
Interpretation: Patients with protein-losing enteropathies generally have alpha-1-antitrypsin stool
concentrations >100 mg/mL. Borderline elevations above the normal range are equivocal for
protein-losing enteropathies.
Reference Values:
< or =54 mg/dL
Clinical References: 1. Florent C, L'Hirondel C, Desmazures C, et al: Intestinal clearance of alpha
1-antitrypsin. A sensitive method for the detection of protein losing enteropathy. Gastroenterology
1981;81:777-780 2. Crossley JR, Elliott RB: Simple method for diagnosing protein-losing enteropathy. Br
Med J 1977;1:428-429 3. Perrault J, Markowitz H: Protein-losing gastroenteropathy and the intestinal
clearance of serum alpha-1-antitrypsin. Mayo Clin Proc 1984;59:278-279
Alpha-1-Antitrypsin, Serum
Clinical Information: Alpha-1-antitrypsin (A1A) is the most abundant serum protease inhibitor and
inhibits trypsin and elastin, as well as several other proteases. The release of proteolytic enzymes from
plasma onto organ surfaces and into tissue spaces results in tissue damage unless inhibitors are present.
Congenital deficiency of A1A is associated with the development of emphysema at an unusually early age
and with an increased incidence of neonatal hepatitis, usually progressing to cirrhosis. See
Alpha-1-Antitrypsin-A Comprehensive Testing Algorithm in Special Instructions.
Useful For: Work-up of individuals with suspected disorders such as familial chronic obstructive lung
disease Diagnosis of alpha-1-antitrypsin deficiency
Interpretation: Patients with serum levels