High prevalence rates of adult silent coeliac disease, as seen in Sweden, must be expected in Denmark.

Aim: To disclose the prevalence of adult "silent" coeliac disease in Denmark and Sweden.

Experimental Design: 1573 Danish and 1866 Swedish healthy blood donors were screened for the presence of serum anti-gliadin antibodies (AGA) by enzyme-linked immunosorbent assay. AGA-positive serum samples were further analysed for IgA anti-endomysium antibodies (EmA) by indirect immunofluorescence microscopy.

Main Results: The Danish donor population had a higher mean age than the Swedish (41.4 years versus 37.6 years) and a higher proportion of females (41% versus 32%), and had a lower mean level of AGA (17.3 units versus 20.6 units). Sixty-one (3.9%) Danish donors had AGA above the cut-off limit, and four of these also had positive EmA tests. Sixty (3.2%) Swedish donors had AGA above the cut-off limit, and five of these also had positive EmA. Coeliac pathology was proven by biopsy in all five coeliac disease-suspected Swedish donors. No small intestinal biopsy was performed in the coeliac disease-suspected Danish donors.

Conclusions: Based upon the finding of EmA in AGA-positive serum samples, silent coeliac disease may be suspected in 1 per 394 Danish blood donors (2.5 per 1,000). A similar rate was proven in 1 per 373 Swedish blood donors (2.7 per 1,000), indicating no major differences in the prevalence of adult silent coeliac disease between the two neighbouring countries.