Modifications of Intestinal Permeability Test Induced by Biliopancreatic Diversion: Preliminary Results

Background: Biliopancreatic Diversion (BPD), excluding the jejunum and part of the ileum from the transit of the food, reduces the absorptive intestinal area available to 250 cm of the distal ileum. The Intestinal Permeability Test (IPT) with Lactulose/Mannitol is performed to assess the intestinal mucosa function. The aim of this study was to investigate the effect of intestinal anatomical modifications induced by BPD on IPT in a group of severely obese patients. Methods: Group A: 18 severely obese subjects who underwent BPD; the IPT was performed before (T_o) and 8.2 ± 0.9 days after BPD (T₁). Group B: nine subjects of Group A; IPT was repeated 96.1 ± 12.7 days (T₂) and 180.4 ± 19.7 days (T₃) after BPD, respectively. IPT was expressed as the %Lactulose/%Mannitol ratio in the urine collected during 5 h after oral administration (normal %L/%M < 0.04). Results: Data from Group A (paired Student's t-test) exhibited significantly higher values in T₁ with respect to T₀ for %L/%M (p < 0.05) and for %L (p < 0.05), and significantly lower values in T₁ with respect to T₀ (p < 0.001) for %M. In the Group B analysis of Variance from T₀-T₁-T₂-T₃ resulted statistically significant (p < 0.05) for %L/%M and %M. Conclusions: The reduction of intestinal absorption surface induced by BPD causes a significative increase of the Lactulose/Mannitol IPT values, showing an intestinal mucosa function impairment. The IPT values improve progressively at 3 and 6 months after this surgical procedure.