Short bowel syndrome and small bowel transplantation

Growth of Intestinal Neomucosa on Pedicled Gastric Wall Flap, a Novel Technique in an Animal Model

Background: Short bowel syndrome (SBS) remains an unsolved issue in modern medicine. Numerous experimental surgical techniques have been proposed in the attempt to increase the intestinal absorptive capacity.Materials and Methods: Ten female Landrace pigs, divided in two groups of 5 (A and B), were explored through a midline incision. A spindle-shaped vascularized full-thickness gastric wall flap (GWF) consisting of part of the major curvature with the gastroepiploic arch preserved was de-epithelialized and then placed as a "patch" to cover an antimesenteric border defect of either a nonfunctional blind intestinal loop (group A) or a functional intestinal loop of the gastrointestinal tract (group B). A spindle-shaped curved, rigid, low density polyethylene (LDPE) splint was sutured on the external surface of the patch in order to prevent shrinkage of GWF and collapse of the intestinal wall in group A.Results: There was a decrease of both dimensions of the patch. Microscopically a thin layer of columnar epithelial cells covered the center of the patch, evolving in shorter, blunt, poorly developed villi with increasing maturation laterally. The patch surface was covered by nearly 90%. In the three animals that died prematurely the coverage of GWF was negligent or suboptimal directly dependent on the length of survival.Conclusions: The hereby-described patching technique demonstrated the growth of intestinal neomucosa on the GWF. The capability of the stomach to provide large flaps and the advantages of the use of native tissues render this animal model valuable for the future research in the field.

Alternative technique to save ischemic bowel segment in management of neonatal short bowel syndrome: A case report

BACKGROUND

Congenital short bowel syndrome (SBS) associated with malrotation, gut volvulus and jejuno-ileal atresia is a very rare condition. It is a severe challenge for surgeons to preserve residual ischemic bowel segment in the management of short bowel syndrome,especially in neonates.

CASE SUMMARY

We report a newborn baby with gut malrotation associated with jejuno-ileal atresia, congenital SBS and jejunal volvulus. Hematemesis and abdominal distention were noted. At laparotomy, malrotation associated with jejuno-ileal atresia, congenital SBS and jenunal volvulus was confirmed. The total length of the small bowel was 63 cm with proximal jejunal bowel segment measuring 38 cm, including 18 cm necrotic segment below the Treitz’s ligament and 20 cm severe ischemic segment. The distal part of the small bowel was 25 cm in length and only about 0.8 cm in diameter. Ladd’s procedure, necrotic segment resection and end-to-back duodeno-ileal anastomosis were performed. The residual severe ischemic jejunum was preserved with single proximal stoma and distal end closure. Three months later, to restore the continuity of the isolated gut segment, end-to-end duodeno-jejunal and jejuno-ileal anastomosis was performed. The entire functional small bowel length increased to 80 cm. Intravenous fluid therapy and parenteral nutrition were discontinued on the 10^th day postoperatively. Twelve months later, her body weight was 9.5 kg.

CONCLUSION

Isolation of severe ischemic bowel segment and staged anastomosis to restore the gut continuity for infants with SBS are safe and feasible.

Parenteral Nutrition and Intestinal Failure

Severe short bowel syndrome (SBS) is a major cause of chronic (Type 3) intestinal failure (IF) where structural and functional changes contribute to malabsorption and risk of micronutrient deficiencies. Chronic IF may be reversible, depending on anatomy and intestinal adaptation, but most patients require long-term nutritional support, generally in the form of parenteral nutrition (PN). SBS management begins with dietary changes and pharmacologic therapies taking into account individual anatomy and physiology, but these are rarely sufficient to avoid PN. New hormonal therapies targeting intestinal adaptation hold promise. Surgical options for SBS including intestinal transplant are available, but have significant limitations. Home PN (HPN) is therefore the mainstay of treatment for severe SBS. HPN involves chronic administration of macronutrients, micronutrients, fluid, and electrolytes via central venous access in the patient's home. HPN requires careful clinical and biochemical monitoring. Main complications of HPN are related to venous access (infection, thrombosis) and metabolic complications including intestinal failure associated liver disease (IFALD). Although HPN significantly impacts quality of life, outcomes are generally good and survival is mostly determined by the underlying disease. As chronic intestinal failure is a rare disease, registries are a promising strategy for studying HPN patients to improve outcomes.

A CD52 antibody impairs mouse-transplanted intestinal tight junctions

BACKGROUND

Induction immunosuppression strategies using a CD52 monoclonal antibody (mAb) have been introduced for small bowel transplantation, resulting in improved outcomes. However, little information is known about the effects of the antibody on the microstructure of the intestinal barrier, which functions to prevent bacterial translocation. In this study, we used a murine orthotopic small bowel transplantation model to investigate the impact of a CD52 mAb on tight junctions (TJs), which are considered a central part of the intestinal barrier, of the transplanted intestine.

MATERIALS AND METHODS

C57BL/6 mice were used as recipients. The grafts were harvested from BALB/c mice in allogeneic groups and C57BL/6 mice in syngeneic groups. The anti-mouse CD52 mAb was applied as a surrogate antibody. Transmission electron microscopy was used to evaluate the TJ ultrastructure. The expression of the TJ proteins occludin and ZO-1 was analyzed by Western blot. The distribution of TJ proteins was observed by immunofluorescence, and the permeability of the transplanted intestine was assessed in vivo using FITC-dextran.

RESULTS

After CD52 mAb application, a compromised TJ ultrastructure was observed. In addition, TJ protein expression (occludin and ZO-1) decreased and the intestinal permeability increased.

CONCLUSIONS

The anti-mouse CD52 mAb impaired the transplanted intestinal TJ and barrier.