BACKGROUND: Antibodies present in coeliac disease may occur in IgA-nephropathy. This raises the question of food intolerance in the disease. Evidence for a true correlation between the two disorders has however been scarce. DESIGN: Sera from 89 patients with IgA-nephropathy and 13 other patients with IgA deposits in the glomeruli of kidney biopsies were analysed for IgA-antibodies to gliadin, endomysium and tissue transglutaminase (92/102 patients). RESULTS: Eleven out of 89 (12.4%) of the patients with IgA-nephropathy and five of the 13 others (38%) had elevated titres of IgA-antibodies to gliadin but, in all cases but one, normal IgA-antibodies to endomysium. Patients with IgA-nephropathy and elevated IgA-antibodies to gliadin had elevated total serum IgA more frequently than patients who had not (p<0.01). Two patients with IgA-nephropathy and one with Hennoch Schönlein's purpura had elevated IgA-antibodies to tissue transglutaminase. Small bowel biopsy in 7 out of 11 IgA-antibodies to gliadin positive patients with IgA-nephropathy was pathologic in three cases (two with Marsh I) . One patient with chronic glomerulnephritis also had Marsh I. CONCLUSIONS: We found no increased frequency of verified coeliac disease in 89 patients with IgA-nephropathy. Two patients with IgA-nephropathy and one patient with chronic glomerulonephritis with IgA deposits in the kidney biopsy had a Marsh I histopathology. The findings suggest a possible link of celiac disease to IgA-nephropathy and a role for antibodies to food antigens in this disorder.