title: Determination of fecal alpha 1-antitrypsin concentration by radial immunodiffusion: two systems compared.
abstract: We compared Helena "QUIPlates" and Calbiochem "LC-Partigen" radial immunodiffusion systems for their ability to measure fecal concentrations of alpha 1-antitrypsin (FA1AT). Reference ranges for FA1AT concentrations in infants receiving various diets, in children, and in adults are given for each system. FA1AT values obtained with Calbiochem LC-Partigen plates averaged 30% greater than those obtained with Helena QUIPlates, but both systems distinguished between normal and high values. Studies involving variations of usual sample-handling procedures showed that storage at room temperature, repeated freezing and thawing, and long-term storage of frozen samples had no significant effect on measured FA1AT concentration. However, values obtained for lyophilized and nonlyophilized samples did not correlate well.
mesh_terms: D000293:Adolescent; D000328:Adult; D001942:Breast Feeding; D002648:Child; D002675:Child, Preschool; D005243:Feces / Q000032:analysis*; D005612:Freeze Drying; D005615:Freezing; D006801:Humans; D005779:Immunodiffusion; D007123:Immunoelectrophoresis, Two-Dimensional; D007223:Infant; D007225:Infant Food; D011933:Reagent Kits, Diagnostic; D012016:Reference Values; D013223:Statistics as Topic; D013696:Temperature; D013997:Time Factors; D000515:alpha 1-Antitrypsin / Q000032:analysis*
chemical_list: D011933:Reagent Kits, Diagnostic; D000515:alpha 1-Antitrypsin