New directions in the aetiology of ulcerative colitis

The causative factors of ulcerative colitis remain unknown. Cellular biochemistry has revealed altered oxidative metabolism, membrane function and synthesis of mucus in colonic epithelial cells in the early stages of ulcerative colitis. Immune studies have highlighted more precise changes in neutrophil and macrophage function in cells of the lamina propria while microbiological evidence has shown a dysbiosis of colonic bacteria related to entero-adhesion, release of bacterial peptides and formation of secondary bacterial metabolites (mercapto fatty acids). A precise sequence of pathological events still needs to be established to account for an acute attack of ulcerative colitis.