THE EFFECT OF PROCTOCOLECTOMY ON SERUM ANTIBODY-LEVELS AGAINST COWS MILK-PROTEINS IN PATIENTS WITH CHRONIC ULCERATIVE-COLITIS, WITH SPECIALREFERENCE TO LIVER CHANGES

Background: The levels of antibodies against cow's milk proteins in ul cerative colitis (UC) were used to study whether mucosal inflammation leads to immune recognition, as a marker of enhanced permeability, of dietary proteins. A further purpose was to study the effect of proctoc olectomy on the serum antibody levels against cow's milk proteins and their relation to biochemical and histologic liver abnormalities assoc iated with ulcerative colitis. Methods: Serum antibody levels against six cow's milk proteins, alpha-casein, alpha-lactalbumin (LA), beta-la ctoglobulin A (LGA), beta-lactoglobulin B (LGB), bovine serum albumin (BSA), and whole milk powder (MP) were determined before and after (me an, 24 months) proctocolectomy in 15 patients with ulcerative colitis. Simultaneously, serum liver enzymes were analyzed. A liver biopsy spe cimen was also obtained at proctocolectomy. Results: Before proctocole ctomy IgA antibody levels were significantly increased against all ant igens except BSA. Increased levels of IgM antibodies against LGA, LGB, and BSA were also detected. IgG antibodies were significantly increas ed only against LGA. After proctocolectomy IgA and IgM antibody levels decreased significantly (p < 0.05) against LGA, LGB, and LA, whereas IgG antibodies increased significantly (p < 0.01). In the patient grou p with abnormal liver histology (n = 9) the IgA antibodies to all cow' s milk proteins were significantly higher (p < 0.02) than in the group with normal liver histology both before and after proctocolectomy. Th e IgA antibody levels showed a significant positive correlation with a lanine amino-transferase and gamma-glutamyltransferase (r value from 0 .460 to 0.721, p value from < 0.05 to < 0.01), but not with alkaline p hosphatase. Conclusions: These results suggest that the inflamed mucos a in UC allows the antigenic contents of the bowel to escape. Proctoco lectomy alters the antibody levels against certain milk proteins, whic h may serve as a model to suggest that proctocolectomy, probably by el iminating inflammation, may have positive effects by reducing the fore ign pathogenic antigen and immune complex load.