The authors have tested the hypothesis that the deficiency of bile acids and the consequent endotoxin translocation might play a role in the pathogenesis of psoriasis. Under normal conditions the bile acids act as detergents (physico-chemical defense) and can protect the body against enteric endotoxins by splitting them into nontoxic fragments and thus preventing the consequent release of cytokines [Persp. Biol. Med. 21 (1977) 70]. A total of 800 psoriasis patients participated in the study and 551 were treated with oral bile acid (dehydrocholic acid) supplementation for 1–8 weeks. The efficacy of the treatment was evaluated clinically and also by means of the Psoriasis Area Severity Index (PASI score). During this treatment, 434 patients (78.8%) became asymptomatic. Of 249 psoriatics receiving the conventional therapy, only 62 (24.9%) showed clinical recovery during the same period of time (P<0.05). The curative effect of bile acid supplementation was more pronounced in the acute form of psoriasis (95.1% of the patients became asymptomatic). Two years later, 319 out of the 551 acute and chronic psoriasis patients treated with bile acid (57.9%) were asymptomatic, compared to only 15 out of the 249 patients (6.0%) receiving the conventional treatment (P<0.05). At the end of the 2-year follow-up, only 10 out of 139 acute psoriasis patients (7.2%) receiving the conventional therapy and 147 out of 184 bile acid treated patients (79.9%) were asymptomatic (P<0.01).

To conclude, the results obtained suggest that psoriasis can be treated with success by oral bile acid supplementation presumably affecting the microflora and endotoxins released and their uptake in the gut.