Prevalence of coeliac disease in the general population of northern spain - Strategies of serologic screening

Background: Coeliac disease (CD) is common in Western countries. In Spain, however, no studies exist on its prevalence. The best method for serologic screening is also unknown. Methods. We determined the IgA and IgG antigliad in antibodies (AGA) and IgA antiendomysium antibodies (AEA) in a sample of 1170 randomly selected subjects From a health area in northern Spain. The p revalence of CD was calculated with a two-step serologic screening method ( first IgA and IgG AGA and then AEA in those positive for AGA) or with only one step with AEA determination. Diagnosis was confirmed by small-intestina l biopsy. Results: When using a two-step strategy, we found 174 (15%) subje cts with AGA. Only one of these was confirmed by means of AEA (prevalence o f CD = 0.9/1000). Two subjects were found to be positive when a one-step st rategy was used (prevalence of CD = 1.7/1000). This yielded an economic sav ing of 19% with regard to the use of a two-step strategy. One new case of C D in a seronegative subject was diagnosed during the study (real prevalence of CD = 2.6/1000; 95% confidence interval = 0.7-8.2). Conclusions: The pre valence of CD in Northern Spain is 2.6/1000 (1:389). One-step serologic scr eening (AEA) is both more economical and more sensitive than the two-step p rocedure (first AGA and then AEA if AGA is positive).