摘要
Objectives: To assess several transglutaminase autoantibody (TGAA) assays in their ability to distinguish celiac disease (CD) in screening- identified child ren with abnormal intestine biopsy specimens from those with normal biopsy speci mens. Study design: Children at risk for CD (n = 54) composed of type 1 diabetic s, first- degree relatives of type 1 diabetics or CD, and HLA- DQ2+ individu als followed from birth received intestine biopsy. Sera obtained at the time of biopsy were tested for TGAA, using the radioimmunoassay and 5 other commercially available enzyme- linked immunosorbent assays. Results: False- positive rates ranged from 28% to 80% . The positive predictive value (PPV ) of the tests ranged from 63% to 84% (lower than reported for symptomatic c hildren). Setting a higher cutoff for each assay maximized PPV. Conclusions: The re are significant quantitative differences among all TGAA assays that could aff ect interpretation of a positive test for CD. The overall false- positive rate for all assays was high in this population. Using the assay as a quantitative ra ther than qualitative tool by increasing the cutoff of positivity to indicate bi opsy increases PPV. Multicenter workshops are needed to identify critical differ ences and to standardize TGAA assays among laboratories.
Objectives: To assess several transglutaminase autoantibody (TGAA) assays in their ability to distinguish celiac disease (CD) in screening- identified child ren with abnormal intestine biopsy specimens from those with normal biopsy speci mens. Study design: Children at risk for CD (n = 54) composed of type 1 diabetic s, first- degree relatives of type 1 diabetics or CD, and HLA- DQ2+ individu als followed from birth received intestine biopsy. Sera obtained at the time of biopsy were tested for TGAA, using the radioimmunoassay and 5 other commercially available enzyme- linked immunosorbent assays. Results: False- positive rates ranged from 28% to 80% . The positive predictive value (PPV ) of the tests ranged from 63% to 84% (lower than reported for symptomatic c hildren). Setting a higher cutoff for each assay maximized PPV. Conclusions: The re are significant quantitative differences among all TGAA assays that could aff ect interpretation of a positive test for CD. The overall false- positive rate for all assays was high in this population. Using the assay as a quantitative ra ther than qualitative tool by increasing the cutoff of positivity to indicate bi opsy increases PPV. Multicenter workshops are needed to identify critical differ ences and to standardize TGAA assays among laboratories.
