Macro- and microscopic mucosal characteristics of the biliopancreatic limb and excluded stomach after Roux-en-y gastric bypass

The Roux-and-Y gastric bypass (RYGBP) changes the anatomy and function of the
gastrointestinal tract. A blind (Y-) loop (duodenum and proximal jejunum) is
created and a large part of the stomach diverted (excluded). This affects the
digestion and absorption of food in the intestine and causes histological
changes in the gastrointestinal tract. Histological examination of the blind
loop after RYGB has not been performed so far and histological changes in the
excluded stomach including the long-term consequences are insufficiently known.

Determination of microbiological, macro and microscopic / histological
characteristics after RYGB, mainly targeted at identifying inflammatory
characteristics, bacterial (over) growth and / or atrophy / metaplasia in the
excluded stomach and the blind loop (duodenum and proximal jejunum).

Cross-sectional study.
The inflammatory, macro and microscopic histological characteristics are
described by endoscopic image and biopsy obtained via transgastric ERCP or
duodeno gastroscopy. Signs and severity of inflammation, atrophy and metaplasia
are described.

Biopsies of the excluded stomach and the blind loop are taken in patients who
have to undergo a laparoscopic assisted ERCP because of occluded choledochus
stones. The additional risks of participation in this study consist of possible
complications due to the biopsy (bleeding, perforations). The overall
percentage of complications in a normal oesophago-gastro-duodenoscopy (OGD)
(incl biopsy) is 0.009-0.13% with a mortality of 0.0009-0.004%, a perforation
risk of 0.0009% and a bleeding risk after biopsy of 0.002%. Participation in
this study thus gives a minimal additional risk on top of the already existing
risks of the endoscopy and laparoscopy.
There are no other additional surveys or visits required.
There is no benefit for the subject to be expected.