In vivo evaluation of immunological status after biliopancreatic bypass for obesity.

Cell mediated immunity was evaluated in vivo by means of the Multitest system in subjects at least one year after biliopancreatic bypass. Quantitative delayed hypersensitivity values were not significantly different between control, obese and partial biliopancreatic bypass subjects, while they were significantly (P less than 0.001) reduced in subjects who had total biliopancreatic bypass. The results demonstrate that cell-mediated immunity is not affected by partial biliopancreatic bypass, but that on the contrary, a severe immunosuppression follows total biliopancreatic bypass. A positive correlation between serum albumin concentration and Multitest score was found in all the operated patients.