IgA antiendomysial antibodies on the umbilical cord in diagnosing celiac disease. Sensitivity, specificity, and comparative evaluation with the traditional kit.

Background: The possibility of assaying antiendomysial antibodies (EmA) on the human umbilical cord instead of monkey esophagus has recently been suggested. We therefore evaluated in patients with celiac disease (CD) the sensitivity and specificity of EmA and of antigliadin antibodies (AGA) for both umbilical cord and monkey esophagus.

Methods: We studied 36 patients with CD and atrophy of the intestinal mucosa (median age, 1.4 years), 14 patients with CD on gluten-free diet for 8-12 months (median age, 3.0 years), 36 controls without gastrointestinal disease (median age, 4.0 years), and 72 patients with cow's milk protein enteropathy (CMPE) (median age, 1.2 years). AGA and EmA on monkey esophagus were assayed with commercially available kits; the slides with umbilical cord were prepared in our laboratory.

Results: There was a perfect concordance between EmA results evaluated on umbilical cord and those on monkey esophagus; there was a doubtful result in only one case on human umbilical cord, which was positive with low titer on monkey esophagus. EmA specificity was 100%; the specificity of AGA IgG varied between 72% and 94% and of AGA IgA between 90% and 100% depending on whether controls without gastrointestinal disorders or patients with CMPE were considered. EmA sensitivity was 97%, AGA IgG was 89%, and AGA IgA 72% sensitive. The only false negative for EmA was positive for AGA IgG and AGA IgA.

Conclusions: Using human umbilical cord as a substrate for EmA may provide the same sensitivity and specificity as offered by the test using monkey esophagus substrate, thus reducing costs and avoiding the use of endangered species.