Diagnostic characteristics of anti-endomysial antibody in the diagnosis of celiac disease-A multicenter prospective observational study.

BACKGROUND: Anti-endomysial antibody (EMA) has demonstrated high specificity and reasonable sensitivity for the diagnosis of celiac disease (CeD). We aimed to evaluate the diagnostic accuracy of EMA in our patients with CeD. MATERIALS AND METHODS: In this prospective study, we included patients of treatment-naïve CeD as cases who were recruited under an Indian National CeD Biorepository and had already tested positive for IgA anti-tTG, hence diagnosed as CeD based on standard criteria. Patients with other enteropathies, functional dyspepsia and gastroesophageal reflux disease, in whom IgA anti-tTG was negative, were taken as controls. Both cases and controls underwent testing for EMA using an immunofluorescence-based assay (Inova Diagnostic, USA). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated. RESULTS: The mean age of patients with CeD and controls was 28.3 ± 12.2 and 35.5 ± 10.72, respectively ( P < 0.001). EMA was positive in only 50.9% (141 of 277) patients with CeD, while in the control group, 1 out of 90 (1.1%) had positive EMA. The sensitivity, specificity, PPV, and NPV were 50.9, 98.9, 99.3, and 39.6%, respectively. Diagnostic odds ratio, positive LR, and negative LR were 92.3, 45.8, and 0.49, respectively. CONCLUSION: EMA test has high specificity and low sensitivity. Only half of adult CeD patients had positive EMA.