Israel Medical Association Journal

Background: Screening for celiac disease is based on the sequential evaluation of serologic tests and intestinal biopsy; an optimal screening protocol is still under investigation. The screening policy of one of the main healthcare providers in Israel (Maccabi) consists of measuring total immunoglobulin A and tissue transglutaminase IgA[1] antibodies and confirming positive results by endomysial antibodies. For IgA-deficient patients antigliadin IgG is measured.

Objectives: To evaluate the use of tTGA[2] as a first-level screening test in patients suspected of having celiac disease

Methods: The results of tTGA and EMA[3] tests over a 3 month period were obtained from the laboratory computer. Letters were sent to the referring physicians of patients with positive tests, requesting clinical information and small intestinal biopsy results. tTGA was performed using an anti-guinea pig tTG-IgA enzyme-linked immunosorbent assay kit.

Results: Overall, 2,505 tTGA tests were performed: 216 (8.6%) were tTGA-positive of which 162 (75%) were EMA-negative (group 1) and 54 (25%) EMA-positive (group 2). Clinical information was obtained for 91 patients in group 1 and 32 in group 2. Small intestinal biopsy was performed in 33 (36%) and 27 patients (84%) in groups 1 and 2, respectively. Celiac disease was diagnosed in 4 biopsies (12%) in group 1 and 23 (85%) in group 2 (P < 0.0001). The positive predictive value was 45% for tTGA and 85% for EMA.

Conclusions: Symptomatic patients with positive tTGA and negative EMA have a low rate of celiac disease compared to those who are tTGA-positive and EMA-positive. Confirmation with EMA is advised when tTGA is performed as a first-level screening for suspected celiac disease.

Background: Celiac disease is common in both children and adults. Small intestinal biopsy is mandatory for establishing a diagnosis. Anti-endomysial antibodies, detected by immunofluorescence, have a sensitivity and specificity close to 100% in the diagnosis of CD[1]. Recently, tissue transglutaminase has been identified as the target autoantigen of antibodies against endomysium, and TTG[2] antibodies are comparable to EMA-IMF[3] in the diagnosis of CD.

Objective: To evaluate a new enzyme-linked immunosorbent assay kit for EMA, compared to EMA-IMF and TTG antibodies in the diagnosis of CD.

Methods: Our study population included all subjects with positive EMA-IMF who underwent intestinal biopsy (n=21). From the same sera, TTG antibodies and EMA-ELISA[4] were determined, and all antibody results were compared to the biopsy findings.

Results: EMA-IMF was able to predict biopsy findings of CD in 19 of 21 cases (90.5%). When patients with biopsy findings compatible with CD and positive EMA-IMF (n=19) were tested for EMA-ELISA and TTG antibodies, 18 of the 19 were positive for both EMA-ELISA and TTG antibodies. A significant correlation was found between EMA-ELISA and TTG antibody titers (r = 0.74, P < 0.001).

Conclusions: Our study demonstrates that EMA-ELISA is comparable to TTG antibodies in the diagnosis of CD, and supports the use of EMA-ELISA as a serologic marker for this disease.