Diagnostic value of duodenal antitissue transglutaminase antibodies in gluten-sensitive enteropathy.

BACKGROUND: In gluten-sensitive enteropathy, antitissue transglutaminase antibodies are synthesized in the duodenum. AIM: To compare the diagnostic yield of these autoantibodies in cultured duodenal biopsies, duodenal aspirate and serum. METHODS: Patients (n = 315, 135 female, 180 male; age: 37.3 +/- 1.1 years) referred for duodenal biopsies, were recruited and HLA-DQ2/DQ8 haplotyped. Histological measurements were made from duodenal biopsies and cultured duodenal biopsies were used for antitissue transglutaminase antibodies analysis by enzyme-linked immunosorbent assay. Duodenal aspirate was collected in a subgroup of 81 patients. Patients were classified, according to their histology, response to a gluten-free diet and DQ2/DQ8 status, as definite, likely or nongluten-sensitive enteropathy. RESULTS: Histology was normal in 59% of patients; 28% had lymphocytic enteritis, 1% had crypt hyperplasia and 13% showed atrophy. In Marsh III patients, there was complete agreement between duodenal and serological antitissue transglutaminase antibodies measurements. Marsh I patients showed a slight antitissue transglutaminase antibodies sensitivity improvement in cultured duodenal biopsy compared to serum in definite (22% vs. 19%) and likely gluten-sensitive enteropathy (20% vs. 14%) patients. Combined serum and cultured duodenal biopsy antitissue transglutaminase antibodies assessment increased serological sensitivity from 19% to 30% in Marsh I patients. CONCLUSION: Duodenal antitissue transglutaminase antibodies detection improves serological determination sensitivity in Marsh I patients, providing diagnostic value and therapeutic impact.