Disappearance of endomysial antibodies in treated celiac disease does not indicate histological recovery.

Abstract

Although serum IgA-class endomysial antibody (EmA) has high sensitivity for villous atrophy (VA) in patients with untreated celiac disease, few studies have attempted to correlate EmA seroconversion with histological recovery after starting a gluten-free diet. We prospectively studied changes in EmA status and in duodenal histology of seropositive patients after dietary treatment. Patients with VA and EmA had repeat EmA testing at 3, 6, and 12 months after starting gluten-free diet, plus assessment of dietary compliance by dietitians and follow-up duodenal biopsy at 12 months. VA before and after treatment was classified as partial (P), subtotal (ST), and total (T). Of 77 patients with newly diagnosed VA and without IgA deficiency, 62 (81%) had EmA: 46 of 57 (81%) with T or STVA and 16 of 20 (80%) with PVA. Of 53 initially EmA-positive patients who completed study criteria, EmA was undetectable in 31 patients (58%) after 3 months' diet, in 40 (75%) after 6 months, and in 46 (87%) after 12 months. However, only 21 patients (40%), all seronegative by 12 months, had complete villous recovery. Only three (33%) of 10 patients with persisting ST or TVA and two (9%) of 22 with PVA remained EmA positive. Four of the five patients with persisting EmA had poor dietary compliance. EmA is a poor predictor of persisting VA after patients have started gluten-free diet, although it may be of value in monitoring dietary compliance. Although there are no clear guidelines regarding the need for follow-up biopsy, EmA seroconversion cannot substitute. The apparent association between dietary compliance and seroconversion suggests that gluten intake may determine whether untreated celiac patients are EmA positive or negative for a given degree of small bowel damage.