Sorbitol H2-breath test versus anti-endomysium antibodies for the diagnosis of subclinical/silent coeliac disease.

BACKGROUND

Recent studies have shown that the prevalence of anti-endomysial antibodies (EMAs) in clinical practice is lower than expected; the aim of our study was therefore to compare the sorbitol H2-breath test (BT) with EMAs in the diagnosis of subclinical/silent coeliac disease and to compare with histologic lesions.

METHODS

We studied 123 consecutive patients with subclinical (96) and silent (27) coeliac disease. Expiratory samples were collected before the patients drank the test solution (5 g of sorbitol in 150 ml of tap water) and every 30 min for 4 h. An increase in H2 concentration of at least 20 ppm over fasting baseline was considered positive for sorbitol malabsorption. EMAs were screened by the indirect immunofluorescence method.

RESULTS

EMAs were positive in 77/96 (80.80%) and sorbitol H2-BT in 94/96 (97.91%) patients with subclinical coeliac disease, while EMAs were positive in 17/27 (62.96%) and sorbitol H2-BT in 26/27 (96.29%) patients with silent coeliac disease (P < 0.001 in both forms of coeliac disease). The best cut-off values in ppm and minutes are higher and shorter in the severe form than in the minor form of intestinal damage, respectively (P < 0.001 in both forms).

CONCLUSIONS

This study indicates that almost all subclinical/silent coeliac patients show abnormal sorbitol H2-BT and that there is a strict correlation between cut-off value (in ppm and minutes) and histologic lesions. In particular, the maximal cut-off value (in ppm and in minutes) correlates statistically with the more severe the grade of intestinal damage. Finally, the prevalence of EMA in subclinical/silent disease is lower than expected.