Screening for coeliac disease in adult insulin-dependent diabetes mellitus.

OBJECTIVES

To study, by sequential screening for gliadin antibodies (GA) and endomysial antibodies (EMA), the prevalence and clinical characteristics of coeliac disease (CD) in adult IDDM patients.

SUBJECTS AND MEASUREMENTS

A series comprising 1664 diabetes patients [848 with IDDM, 745 with non-insulin-dependent diabetes (NIDDM) and 71 with secondary diabetes] were screened for GA. IgA- or IgG-GA positive sera were analysed for EMA.

RESULTS

IgA-GA were more frequent in all the diabetes subgroups (13.7% in IDDM,12.3% in NIDDM and 23.9% in secondary diabetes, P < 0.001 in all three cases) than among healthy blood donors (4.7%). Two patients with NIDDM had CD. Of the IDDM group (n = 848), 8 had previously diagnosed CD and 14 more (of whom 7 could be biopsied) were EMA positive. All had villous atrophy. The minimum prevalence of CD (including probable cases) in IDDM was 2.6% (22/848). Patients with previously known CD had more symptoms (P < 0.001), more deficiency states (P < 0.001) and more autoimmune diseases (P < 0.04) than those identified by screening. IDDM patients with a diabetes duration of 31-40 years were characterised by a higher prevalence of CD than patients with a duration of less than 30 years (6.7% vs. 1.7%; P < 0.02).

CONCLUSIONS

Serial analysis of GA and EMA confirmed a high prevalence of CD in adult IDDM (2.6%). False-positive IgA-GA test results are frequent in patients with diabetes, irrespective of type. EMA analysis is the preferable screening tool for CD in diabetes.