Function and structure of the mucosa of continent ileostomy reservoirs in dogs.

Abstract

SUMMARY Continent ileostomy reservoirs were constructed in dogs. Nine to 29 days after formation of the pouches, they were excised together with a loop of adjacent ileum for biochemical and morphological assessment. The villous and epithelial cell heights were reduced, whereas villous width and mitotic index were increased. The mucosa of the pouch was able to absorb phenylalanine and f-methyl-glucoside against a concentration gradient, although this absorptive capacity was lower than that of normal ileum. Similar considerations applied to oxygen consumption. The results indicate that the mucosa of the pouch undergoes transformation, but the integrity of the epithelial layer is maintained.Recently a 'continent ileostomy' was devised (Kock, 1969(Kock, , 1973Kock, Darle, Kewenter, Myrvold, and Philipson, 1974) and introduced as an alternative to the conventional ileostomy in man. The continent ileostomy utilizes an intraabdominal reservoir constructed from the distal ileum for collection and temporary storage of the intestinal contents.Clinical follow-up studies in patients with continent ileostomies have revealed morphological changes in the mucosa of the intraabdominal reservoir, which included decreased villous height and increased epithelial turnover (Philipson, Brandberg, Jagenburg, Kock, Lager, and Ahrdn, 1975). However, the ability of the intestines of these patients to absorb L-phenylalanine, D-xylose, fat, and vitamin B12 is the same as that of patients with conventional ileostomies (Jagenburg, Dotevall, Kewenter, Kock, and Philipson, 1971;Jagenburg, Kock, and Philipson, 1975). In spite of the presence of an increased number of microorganisms (Brandberg, Kock, and Philipson, 1972;Philipson et al, 1975), local vitamin B12 absorption has been demonstrated in the reservoirs of some patients The absorptive capacity of the mucosa used for the construction of the reservoir is difficult to study in vivo under standardized conditions. For this reason, animal experiments have been performed to estimate in vitro the transport of amino acids and sugars by the mucosa of the reservoir. Materials and Methods SURGICAL PROCEDURENineteen mongrel dogs of both sexes weighing 9-5-17-5 kg were used. Paramedian laparotomy was performed under pentobarbital anaesthesia and sterile conditions. The ileum was divided about 7 cm from the ileocaecal valve, and the distal stump of ileum was closed. The construction of the ileostomy reservoir corresponded exactly to that described previously for clinical use (Kock, 1973). Briefly, a loop of ileum was formed into a U, the walls of the U were sewn together, and the loop was opened longitudinally. The terminal unsplit segment was employed for the construction of the nipple valve. Then the bottom of the U was folded up and the free edges were sewn together to form a hermetic pouch. The completed pouch was then placed in the abdomen and fixed in position. The outlet was passed through the abdominal wall by means of a separate incision and an ileostomy was created.Before closure of the a...

Structural and Functional Alterations in the Mucosa of Self-Filling Intestinal Blind Loops in Rats

“…The morphological changes in the mucosa of the blind loop that we found are similar to those observed when the mucosa was exposed to toxic intraluminal stress, as in small-intestinal loops transposed into the colon (Philipson, 1975;Menge et al, 1977), exposed over long periods to lactic acid (Riecken, Bloch, Menge, Idelberger, Kramer, Miller & Lorenz-Meyer, 1972) or transformed into continent ileostomy pouches (Philipson, Kock, Robinson, Menge & Mirkovitch, 1975). Although the increase in villus height and crypt length is reminiscent of that occurring in intestinal remnants after resection, several morphological characteristics differ between these two situations .…”

Continent Ileostomy

“…Here the villi were absent near the nipple and lowered as far as 100 cm above it while the mucosa was high and metaplastic, i.e. the number of goblet cells were reduced and the surface epithelium was lowered [7], In some places it was missing. These changes were most marked in the animals with a preformed reservoir ( fig.…”

“…The ileostomy with nipple valve anti reservoir (3 animals) was constructed as de scribed by Philipson et al (7], Briefly, a 35-to 40-cm loop of the terminal ileum was formed into a *U\ sewn together, and opened longitudinally. A 15-cm terminal segment, not incorporated in the 'U' was then used for a nipple valve.…”

“…Dogs were the only domestic animal available which, without con straints, would allow the necessary handling. The construction of a reser voir in dogs, however, is hampered by high mortality and reduced intes-G runi r Holti r Woxiiolt tinal absorption [7]. This being known, we saw no reason to perform elaborate resorption studies.…”

Strukturelle und funktionelle Befunde beim experimentellen Blindsacksyndrom

“…[8] oder wie sie in einer Diinndarmtasche bei kontinenter KocKscher Ileostomie beim Menschen zur Ausbildung kommen[7].…”