PROSPECTIVE-STUDY OF MORPHOLOGIC AND FUNCTIONAL-CHANGES WITH TIME IN THE MUCOSA OF THE ILEOANAL POUCH - FUNCTIONAL APPRAISAL USING TRANSMUCOSAL POTENTIAL DIFFERENCES
J. Garciaarmengol et al., PROSPECTIVE-STUDY OF MORPHOLOGIC AND FUNCTIONAL-CHANGES WITH TIME IN THE MUCOSA OF THE ILEOANAL POUCH - FUNCTIONAL APPRAISAL USING TRANSMUCOSAL POTENTIAL DIFFERENCES, Diseases of the colon & rectum, 41(7), 1998, pp. 846-853
This study was undertaken to investigate the morphologic and functiona
l changes with time in the mucosa of the ileoanal pouch. METHODS: A mo
rphologic study by histopathologic analysis, mucosal morphometry, and
mucin histochemistry and a functional study by analysis of transmucosa
l potential difference were performed in 27 patients with an ileoanal
J-pouch after restorative proctocolectomy for ulcerative colitis. In 1
9 patients with a normal ileoanal pouch. two prospective follow-up ana
lyses were performed after median functional pouch times of 14 and 39
months. We also evaluated eight patients with the diagnosis of pouchit
is (median follow-up, 52.5 months). RESULTS: Tn the normal ileoanal po
uch group, some degree of chronic and acute inflammatory; infiltration
was identified in 100 percent and 63.2 percent of cases, respectively
, with no significant differences being observed between the two follo
w-up analyses. The mean villous atrophy index at the first and second
follow-up was 0.54 and 0.52, respectively significantly lower (P < 0.0
01; an indication of a greater degree of villous atrophy) than the val
ue obtained from the control group with a healthy terminal ileum (0.77
). The group of patients with pouchitis exhibited statistically signif
icant differences in the degree of acute and chronic inflammatory infi
ltration, the extent of ulceration, the crypt depth, and the villous a
trophy index, compared with patients without pouchitis. Tn the normal
ileoanal pouch group, the: median percentage of sulfomucin with each d
egree of atrophy (1 = mild; 2 = moderate: and 3 = severe) was 2.6, 4.5
, and 20.9 percent, respectively. In patients with pouchitis, the medi
an percentage of sulfomucin was 5.9 percent. The mean transmucosal pot
ential difference at the first follow-up (- 25.3 mV) was significantly
lower (P = 0.001) than at the second (- 30.4 mV). Significant differe
nces were apparent with respect to both the normal ileum (- 8.9 mV) an
d the normal rectum (- 40.2 mV). CONCLUSION: These results suggest tl-
lat the ileal pouch behaves as a neorectum, with different degrees of
colonic metaplasia from a morphologic and a functional perspective.