Meta‐analysis: deamidated gliadin peptide antibody and tissue transglutaminase antibody compared as screening tests for coeliac disease

Abstract

Following the appreciation of the importance of gliadin deamidation in the immunopathogenesis of coeliac disease, diagnostic tests based on antibodies to deamidated gliadin peptides have been developed and shown to have high sensitivity and specificity. To compare the performance of the deamidated gliadin peptides antibody test with the current standard, the tissue transglutaminase antibody test, through a meta-analysis of published studies. Databases from 1998 to 2008 were searched for relevant studies. These were assessed for methodological quality and standard statistical tests were applied to compare particularly the sensitivity and specificity of the two tests for the diagnosis of coeliac disease. Most studies had methodological flaws, especially ascertainment bias. The pooled sensitivities for the deamidated gliadin peptides antibody and tissue transglutaminase antibody tests were 87.8% (95% CI, 85.6-89.9) and 93.0% (95% CI, 91.2-94.5) respectively and the pooled specificities were 94.1% (95% CI, 92.5-95.5) and 96.5% (95% CI, 95.2-97.5) respectively. Although both tests perform well, the tissue transglutaminase antibody test outperforms the deamidated gliadin peptides antibody test and remains the preferred serological test for the diagnosis and/or exclusion of coeliac disease.