DO INTESTINAL HYPERPERMEABILITY AND THE RELATED FOOD ANTIGENS PLAY A ROLE IN THE PROGRESSION OF IGA NEPHROPATHY .1. STUDY OF INTESTINAL PERMEABILITY

Intestinal permeability was investigated by using Cr-51-EDTA as a prob e molecule in 29 patients with immunoglobulin A nephropathy (IgA NP) a nd 20 healthy controls in 1990. Intestinal permeability was significan tly higher in the IgA NP patients than in the controls (IgA NP, 3.86 /- 0.29%; controls, 2.72 +/- 0.23%, p < 0.005). There was a significan t relation between the manifestations of the disease (proteinuria and/ or microhematuria) and the increased intestinal permeability (p < 0.05 ). By 1994, after an interval of 4 years, average intestinal permeabil ity in the 21 patients available for study had not changed (3.80 +/- 0 .36 vs. 4.57 +/- 0.63%) and was significantly higher than in the contr ols (p < 0.02). In patients with elevated serum IgA levels (serum IgA >3.2 g/l; n = 15) there was a significant correlation between serum Ig A levels and the degree of intestinal permeability (p < 0.02). During the 4-year period, the patients' kidney function deteriorated (n = 25; creatinine clearance in 1990, 92.4 +/- 6.1 ml/min; in 1994, 73.9 +/- 7.6 ml/min; p < 0.0002), the deterioration being greater in patients w ith increased intestinal permeability. There was no relation between t he histologic grade of the biopsy specimen, hypertension and intestina l permeability. These data collected over a 4-year period suggest that in IgA NP increased intestinal permeability may play a role in the pa thogenesis of the disease and adversely influence its progression.