Choice of Allograft in Patients Requiring Intestinal Transplantation: A Critical Review

Indications for Multivisceral Transplantation: A Systematic Review

Consensus remains elusive in the definition and indications of multivisceral transplantation (MVT) within the transplant community. MVT encompasses transplantation of all organs reliant on the celiac artery axis and the superior mesenteric artery in different combinations. Some institutions classify MVT as involving the grafting of the stomach or ascending colon in addition to the jejunoileal complex. MVT indications span a wide spectrum of conditions, including tumors, intestinal dysmotility disorders, and trauma. This systematic review aims to consolidate existing literature on MVT cases and their indications, providing an organizational framework to comprehend the current criteria for MVT.

[Indications and results of intestinal transplantation for short bowel syndrome after mesenteric ischemia]

BACKGROUND

Intestinal transplantation (ITx) is the only causal treatment for complicated chronic intestinal failure after mesenteric ischemia and impending failure of parenteral supplementation. Isolated or combined ITx with the inclusion of the intestine is associated with demanding immunological, perioperative and infection associated challenges.

AIM

The characterization of chronic intestinal failure, the indications, transplant survival, transplantation techniques and success rates.

MATERIAL AND METHODS

Collection, summary and critical appraisal of international guidelines, the guidelines of the German Medical Chamber, and the international literature.

RESULTS

The first successful ITx were performed in 1987 and 1988 at the University of Kiel Germany and the University of Pittsburgh, USA. The number of ITx rose continuously but in phases from the end of the 1990s to over 200 per year but has currently decreased to 100-150 per year due to optimized intestinal rehabilitation. While the 1‑year and 3‑year transplant survival rates were 30% and 20% before 1991, they increased in phases up to 60% and 50%, respectively, after 1995 and have now achieved almost 80% and 70%, respectively.

CONCLUSION

The substantial improvement in the results of ITx can be partly explained by progress in operative techniques, intensive care medicine and a better understanding of mucosal immunity; however, optimized strategies in immunosuppression as well as prevention of infectious diseases and malignancies have also made decisive contributions.

[Chronic intestinal failure]

The term intestinal failure (IF) is understood as the transient or irreversible loss of the resorptive capacity of the bowels. This includes a multitude of diseases, some of which have anatomical causes and others functional causes. The functional capacity (absorption and motility) of the remaining digestive tract and the bacterial overgrowth and false colonization of the small bowel are of prognostic importance. After exclusion of pathological intestinal findings, such as stenosis and dilatation, initially conservative treatment is employed with the aim of intestinal adaptation. Before failure or complications, initially conservative surgery and then organ replacement by transplantation should be considered. The IF is a temporary or permanent condition. For adults a length of 100cm small bowel without the colon, 60cm still with continuity to the colon and 35cm small bowel with complete preservation of the colon including the ileocecal valve are potentially sufficient for intestinal autonomy.

Identifying the Growth Factors for Improving Neointestinal Regeneration in Rats through Transcriptome Analysis Using RNA-Seq Data

Using our novel surgical model of simultaneous intestinal adaptation "A" and neointestinal regeneration "N" conditions in individual rats to determine feasibility for research and clinical application, we further utilized next generation RNA sequencing (RNA-Seq) here in normal control tissue and both conditions ("A" and "N") across time to decipher transcriptome changes in neoregeneration and adaptation of intestinal tissue at weeks 1, 4, and 12. We also performed bioinformatics analyses to identify key growth factors for improving intestinal adaptation and neointestinal regeneration. Our analyses indicate several interesting phenomena. First, Gene Ontology and pathway analyses indicate that cell cycle and DNA replication processes are enhanced in week 1 "A"; however, in week 1 "N", many immune-related processes are involved. Second, we found some growth factors upregulated or downregulated especially in week 1 "N" versus "A". Third, based on each condition and time point versus normal control tissue, we found in week 1 "N" BMP2, BMP3, and NTF3 are significantly and specifically downregulated, indicating that the regenerative process may be inhibited in the absence of these growth factors. This study reveals complex growth factor regulation in small neointestinal regeneration and intestinal adaptation and provides potential applications in tissue engineering by introducing key growth factors identified here into the injury site.