Effects of intestinal transplantation on postprandial motility and regulation of intestinal transit

Late transplantation period of mice fetal intestine grafts: morphometric aspects

Morphometric evaluation of the fetal intestinal graft in the late post-transplant period was done by using C57BL/6 mice. Under anesthesia, after hysterotomy, a transversal laparotomy was done in the fetus to harvest all intestines. Grafts, cleaned from its mesentery, and divided were transplanted into the preperitoneum space, from male mice, C57BL/6 strain. Thirty days after, mice were killed, and the graft was analyzed with HE stain and S-100 protein. All grafts as well as fetal and adult intestines were evaluated as controls. All developed grafts showed muscular layer and positivity for S-100 protein as the adult intestines. The goblet cells, absent in fetal intestines, were in larger number in isogeneic grafts than in adult intestines, even with lower villus. These findings showed sharp progress of the isogeneic graft from fetal to adult intestine, suggesting that they can be viable and might be functionally appropriate in the late period after transplantation.

Radiologic imaging of the transplanted bowel

Background

The radiologic evaluation of the transplanted bowel is largely unknown and rather complex because it involves several techniques that depend on indications and times that have not been fully defined.

Methods

From December 2000 to November 2002 in the Section of Radiology I of the University of Modena and Reggio Emilia (Modena, Italy), 11 patients with transplanted bowel were studied with different methods: traditional radiologic evaluation with contrast agent (all patients), evaluation of transit time with radiopaque markers (five patients), ultrasonographic (US) evaluation of the intestinal wall and Doppler US of the vascular axes (five patients), computed tomographic (CT) evaluation (all patients), and magnetic resonance (MR) evaluation of the bowel and the vascular axes (five patients). Traditional contrast examination enabled evaluation of the gastroesophageal transit and cardia functionality; anatomy and integrity of the anastomoses (proximal and distal); time of gastric emptying; morphology, tone, and kinesis of the transplanted small bowel loops and time of global transit. The study of transit with radiopaque markers was carried out in five patients to define the time of transit through the entire transplanted bowel, confirm recovery of intestinal motility, and identify possible abnormalities. The US examination was carried out in five patients to evaluate the morphology, thickness, and echo structural features of the intestinal loops. Color Doppler was performed to visualize the superior mesenteric artery and a wall arteriole of the sampled loop. CT examination was performed 2 to 4 weeks after surgery to evaluate the anatomy of the transplanted organs, arterial and venous anastomoses in case of complications identified with other methods or suspected, and periodically in the follow-up of patients who underwent transplantation due to Gardner syndrome. The protocol for MR evaluation of the bowel included coronal single-shot fast spin-echo T2-weighted sequences, axial and/or sagittal single-shot fast spin-echo T2-weighted sequences, coronal fast multiplanar spoiled gradient-echo (FMP- SPGR) sequences, coronal FMPSPGR sequences with and without administration of intravenous paramagnetic contrast agent, and axial or sagittal FMPSPGR fat-saturated sequences performed after dynamic gadolinium administration.

Results and conclusion

The study of transit with radiopaque markers was useful in patients with chronic intestinal pseudo-obstruction because it identified recovery and normalization of motility. Traditional contrast examination of the gastrointestinal tract continues to play an important role in transplanted patients because it is a simple examination that allows evaluation of the graft anatomy and recovery of motility of the residual native bowel and the transplanted loops. Moreover, it plays a crucial role in early detection of major postoperative complications such as intestinal obstruction, perforation, fistulas, and anastomotic complications (stenosis and dehiscence). CT examination is crucial for the detection of fluid collections, abscesses, and fistulas because it can serve as a guide of drainage and during follow-up of patients with Gardner syndrome can be used to investigate all possible sites in which desmoids might arise in addition to their relation to the graft. Because patients with transplanted bowel are generally rather a young population of reproductive age and because of technologic advances, MR may represent an effective method that does not use ionizing radiation and can therefore substitute for traditional radiologic evaluation. US represents a quick examination technique that is easily available and well tolerated by patients, and it has a role to play in the follow-up of transplanted patients and in the identification of major postoperative complications. However, its role in monitoring possible rejection remains to be defined with studies on wider and more representative samples.

Transplante de intestino delgado

RACIONAL: Avanços da biotecnologia e o desenvolvimento de novas drogas imunossupressoras melhoraram os resultados do transplante de intestino delgado. Esse transplante é atualmente indicado para casos especiais da falência intestinal. OBJETIVO: A presente revisão realça os recentes desenvolvimentos na área do transplante de intestino delgado. MATERIAL E MÉTODO: Mais de 600 publicações de transplante de intestino delgado foram revisadas. O desenvolvimento da pesquisa, novas estratégias de imunossupressão, monitorização do enxerto e do receptor, e avanços na técnica cirúrgica são discutidos. RESULTADOS: Realizaram-se cerca de 700 transplante de intestino delgado em 55 centros: 44% intestino-fígado, 41% enxerto intestinal isolado e 15% transplante multivisceral. Rejeição e infecção são as principais limitações desse transplante. Sobrevida de 5 anos na experiência internacional é de 46% para o transplante de intestino isolado, 43% para o intestino-fígado e de cerca de 30% para o transplante multivisceral. Sobrevidas prolongadas são mais freqüentes nos centros com maior experiência. Em série de 165 transplantes intestinais na Universidade de Pittsburgh, PA, EUA, foi relatada sobrevida do paciente maior do que 75% no primeiro ano, 54% em 5 anos e 42% em 10 anos. Mais de 90% desses pacientes assumem dieta oral irrestrita. CONCLUSÃO: O transplante de intestino delgado evoluiu de estratégia experimental para uma alternativa viável no tratamento da falência intestinal permanente. Promover o refinamento da terapia imunossupressora, do manejo e prevenção de infecções, da técnica cirúrgica e da indicação e seleção adequada dos pacientes é crucial para melhorar a sobrevida desse transplante.

Combined small bowel and reduced auxiliary liver transplantation: Case report

AIM: To present a case of combined small bowel and reduced auxiliary liver transplantation.

METHODS: A 55-year-old patient with short bowel syndrome and TPN-related liver dysfunction received small bowel transplantation combined with a reduced auxiliary liver graft. A liver was added to restore the patient's liver function and to protect the intestinal allograft from rejection. His own liver was not removed.

RESULTS: Without donor pretreatment and by conventional immunosuppresive therapy following transplantation, the patient experienced had only one episode of mild intestinal rejection, which was easily reversed by treatment with Methylprednisolone. No liver rejection occurred. Unfortunately, the patient died of heart and lung failure 30 d after transplantation, despite successful graft replacement. Histopathologic examination of specimens after death demonstrated normal structure in both intestinal and liver grafts.

CONCLUSION: The auxiliary liver graft might play a role in preventing intestinal allograft rejection. However, the observation period in this case is short. Further study is needed to determine the risks, effect on the protecting the small-bowel from rejection, and feasibility of general application of this procedure.

Molecular and functional observations on the donor intestinal muscularis during human small bowel transplantation

BACKGROUND & AIMS

Ischemia-reperfusion injury or intestinal manipulation evokes an inflammatory response within the intestinal muscularis that is associated with intestinal dysmotility. We hypothesize that human small intestinal transplantation induces an analogous response.

METHODS

Human intestinal graft specimens were obtained during transplantation and compared with specimens removed early during elective bowel resections. Inflammatory gene expression was quantified by real-time reverse-transcription polymerase chain reaction. Histochemistry and immunohistochemistry were used to characterize leukocyte infiltration and macrophage activation. In vitro circular muscle contractility and intracellular electric neuromuscular transmission in response to electric field stimulation (EFS) were measured.

RESULTS

Messenger RNA (mRNA) values were significantly elevated before reperfusion and further increased during reperfusion (4 hour reperfusion: interleukin [IL]-6, 311-fold; monocyte chemoattractant protein [MCP-1, 122-fold; IL-8, 338-fold; epithelial neutrophil-activating peptide-78 [ENA-78], 56-fold; intercellular adhesion molecule-1 [ICAM-1], 9-fold; and cyclooxygenase-2 [COX2], 37-fold) over elective specimens. Neutrophils and monocytes extravasated in increased numbers in whole mounts before and after reperfusion over the elective specimens. Activated resident macrophages were identified as a major source of inflammatory mediators. Muscle contractions and neuromuscular transmission were markedly attenuated in the grafts.

CONCLUSIONS

The data suggest that manipulation during organ harvesting initiates a functionally relevant molecular and cellular inflammatory response within the graft muscularis that is potentiated during the reperfusion period. Significant mechanical and neuromuscular functional alterations occurred during the transplant process.

Surgery of the small intestine

The small intestine is the portal of entry of virtually all nutrients and is also the site of diverse inflammatory and neoplastic diseases. This field has recently attracted intense excitement as a result of novel clinical and experimental techniques, combined modality therapies, and basic science applications. This review will highlight important clinical advances in surgery for Crohn disease, short bowel syndrome, transplantation, trauma, and polyposis. Promising experimental approaches, novel methods of clinical assessment, and multimodality treatment will also be considered.