Outcome of pigs with short gut syndrome submitted to orthotopic intestinal transplantation.

PURPOSE: To evaluate the current model of small bowel resection and intestinal transplantation in pigs. METHODS: Forty two Large White pigs were distributed in five groups: G1(n=6), G2(n=6) and G3(n=6) were submitted to 80%,100% and 100% plus right colon resection respectively and G4(n=7) and G5(n=5) to 100% SBR plus IT without and with immunosuppression based on Tacrolimus and Mycophenolic acid. Evaluation included weight control, clinical status, biochemical analysis and endoscopies for graft biopsies. Follow-up in G1 and 2 was 84 days, while in G3, four and five was ± three weeks. RESULTS: G1 increased weight suggesting adaptation while G2 and 3 loused weight and inadequate adaptation. G4 and 5 died of acute cellular rejection (ACR) and sepses respectively. Overall survival in G1, 2, 3, 4 and 5 at 30 days was 100, 100, 0 and 20 %, respectively. Medium survival in G4 and 5 was 14 and 16 days. CONCLUSIONS: The resection of 80% of small intestine in pigs is not suitable for short bowel syndrome induction. Intestinal transplantation with the proposed immunosuppression protocol was effective in prevent the occurrence of severe acute rejection, but inappropriate to increase recipients survival.

Outcome of pigs with short gut syndrome submitted to orthotopic intestinal transplantation

PURPOSE: To evaluate the current model of small bowel resection and intestinal transplantation in pigs. METHODS: Forty two Large White pigs were distributed in five groups: G1(n=6), G2(n=6) and G3(n=6) were submitted to 80%,100% and 100% plus right colon resection respectively and G4(n=7) and G5(n=5) to 100% SBR plus IT without and with immunosuppression based on Tacrolimus and Mycophenolic acid. Evaluation included weight control, clinical status, biochemical analysis and endoscopies for graft biopsies. Follow-up in G1 and 2 was 84 days, while in G3, four and five was ± three weeks. RESULTS: G1 increased weight suggesting adaptation while G2 and 3 loused weight and inadequate adaptation. G4 and 5 died of acute cellular rejection (ACR) and sepses respectively. Overall survival in G1, 2, 3, 4 and 5 at 30 days was 100, 100, 0 and 20 %, respectively. Medium survival in G4 and 5 was 14 and 16 days. CONCLUSIONS: The resection of 80% of small intestine in pigs is not suitable for short bowel syndrome induction. Intestinal transplantation with the proposed immunosuppression protocol was effective in prevent the occurrence of severe acute rejection, but inappropriate to increase recipients survival. .

Quantitative in situ analysis of FoxP3+ T regulatory cells on transplant tissue using laser scanning cytometry.

There is abundant evidence that immune cells infiltrating into a transplanted organ play a critical role for destructive inflammatory or regulatory immune reactions. Quantitative in situ analysis (i.e., in tissue sections) of immune cells remains challenging due to a lack of objective methodology. Laser scanning cytometry (LSC) is an imaging-based methodology that performs quantitative measurements on fluorescently and/ or chromatically stained tissue or cellular specimens at a single-cell level. In this study, we have developed a novel objective method for analysis of immune cells, including Foxp3(+) T regulatory cells (Tregs), on formalin-fixed /paraffin-embedded (FFPE) transplant biopsy sections using iCys® Research Imaging Cytometer. The development of multiple immunofluorescent staining was established using FFPE human tonsil sample. The CD4/CD8 ratio and the population of Tregs among CD4(+) cells were analyzed using iCys and compared with the results from conventional flow cytometry analysis (FCM). Our multiple immunofluorescent staining techniques allow obtaining clear staining on FFPE sections. The CD4/CD8 ratio analyzed by iCys was concordant with those obtained by FCM. This method was also applicable for liver, small intestine, kidney, pancreas, and heart transplant biopsy sections and provide an objective quantification of Tregs within the grafts.

In situ spectroscopic detection of SMSI effect in a Ni/CeO2 system: hydrogen-induced burial and dig out of metallic nickel.

In situ APPES technique demonstrates that the strong metal support interaction effect (SMSI) in the Ni-ceria system is associated with the decoration and burial of metallic particles by the partially reduced support, a phenomenon reversible by evacuation at high temperature of the previously absorbed hydrogen.

Segmental xanthomatosis of the small intestine. A case report and review of the literature.

Intestinal xanthomatosis is a rare, nonneoplastic lesion that may involve the small bowel in a localized or generalized way. It most probably represents a nonspecific response to a previous injury. Most cases are not suspected clinically. They are diagnosed by endoscopy/biopsy, surgical specimen, or autopsy. It may be a cause of clinically significant obstruction and should be included in the differential diagnosis with other causes of bowel obstruction, particularly in patients with history of radiation therapy or chemotherapy. We report a case of segmental xanthomatosis involving 50 cm of the terminal ileum. The patient was a 22-year-old man who developed intestinal obstruction 16 years after radiation therapy for Ewing sarcoma of the right hip. A review of the English literature revealed that only rare cases have been previously reported.

Analysis of acute and chronic rejection in multiple organ allografts from retransplantation and autopsy cases of multivisceral transplantation.

BACKGROUND: Small intestinal allografts in multivisceral transplantation are felt to be more susceptible to acute cellular rejection (ACR) and chronic rejection (CR) when compared with other allografts although there is little direct evidence for this impression. METHODS: A total of 48 cases of multiple allograft specimens (37 autopsy and 11 explanted allograft cases) from 41 patients were evaluated in this study. Histopathologic assessments were performed with special concern to ACR and CR in allografts. The numbers of allografts available for evaluation were liver 37, small intestine 47, stomach 41, pancreas 45, and large intestine 25. RESULTS: Among 48 cases, 15 cases showed ACR (ACR case) and 12 showed CR (CR case) in at least one organ. In ACR cases, there was a statistically significant difference of organ-specific susceptibility to ACR among multivisceral allografts with the small intestinal allograft being the most susceptible (P<0.05). Severe ACR were observed only in small and large intestinal allografts. In CR cases, there was no statistically significant difference of organ-specific susceptibility to CR among multivisceral allografts with a tendency for the pancreas allograft to be the most susceptible (P=0.35). CONCLUSIONS: Our study clearly indicated variation in organ susceptibility to ACR and CR. Small intestinal allografts were the most susceptible organ to ACR in frequency and severity. Pancreatic allografts may be more susceptible to CR in comparison with ACR.

Subclinical rejection in the initial postoperative period in small intestinal transplantation: a negative influence on graft survival.

BACKGROUND: Subclinical rejection (SCR) is a known entity in various solid organ transplants but not in intestinal transplantation. METHODS: The purpose of this study is to characterize the presence and effect of SCR in small intestinal transplantation (Itx). A total of 151 patients who underwent Itx and maintained a functioning graft for at least 3 months after Itx were investigated. The clinicopathological characteristics associated with a SCR episode within 3 months after Itx were analyzed. Cox regression with the landmark method (the landmark time being 3 months after Itx) was used for the analyses of overall graft survival and cause-specific hazard rate of SCR. RESULTS: A total of 2744 small intestinal transplant biopsies within 3 months after Itx were available for retrospective evaluation; 171 cases (6.2%) were determined as SCR and 78 patients (51.7%) experienced SCR episode within 3 months after Itx. Adult patients were associated with a significantly higher occurrence of a SCR episode (P=0.001). Overall graft survival at 5 years posttransplant for patients experiencing SCR within 3 months posttransplant and for patients without SCR was 37.2% and 60.2%, respectively (P=0.009). Cause-specific hazard rate analysis showed that a SCR episode was associated with a significantly higher hazard rate of death due to infection (P=0.005). CONCLUSIONS: A SCR episode in the initial postoperative period of Itx is a significant factor for unfavorable graft prognosis, likely representing alloimmune injury ultimately resulting in patient morbidity due to infection.

Contemporaneous chronic rejection of multiple allografts with principal pancreatic involvement in modified multivisceral transplantation.

The patient was a 10 yr-old-male with short gut syndrome secondary to Hirschsprung's disease, who underwent a modified (no liver) multivisceral transplant (stomach, pancreas, small and large intestine). The patient experienced malabsorption early in the post-operative course and had been dependent on a combination of enteral and intravenous nutrition. He developed symptoms of bowel obstruction and was suspected to have chronic rejection by an exploratory laparotomy four yr after transplant. Re-transplantation of a multivisceral transplant (stomach, pancreas, liver, small and large intestine) was performed. Microscopic examinations of the explanted allograft organ block revealed varying degrees of chronic rejection in many of the organs but with the pancreatic allograft being affected most severely. The malabsorption symptom following the first transplant may have been caused by the early onset of chronic pancreatic allograft dysfunction. Our case indicates varying severity of chronic rejection among multiple allografts where the pancreatic allograft appeared most susceptible to chronic rejection.

Simultaneous antibody-mediated rejection of multiple allografts in modified multivisceral transplantation.

The patient was an 8-year-old-female with a history of intestinal pseudo-obstruction who underwent a modified multivisceral transplant (stomach, duodenum, pancreas, and small intestine). Following transplantation, she developed HLA antibody (donor-specific and non-donor-specific). Donor-specific HLA antibodies decreased 2 weeks after transplantation, but non-donor-specific HLA antibodies remained high throughout the posttransplant course. The patient experienced repeated acute rejection episodes throughout the post-transplant course, ultimately resulting in the replacement of all allografts 250 days after the initial transplantation. The explanted allografts all revealed acute vascular rejection, but at varying degrees. There was also concurrent chronic rejection, with the intestinal allograft being affected most severely. This case suggests that HLA antibodies played a critical role in antibody-mediated acute rejection and chronic rejection and that there is varying susceptibility to this form of rejection among multiple allografts.

Fine-needle aspiration diagnosis of angiosarcoma of the spleen: a case report and review of the literature.

Primary angiosarcoma of the spleen is a very rare neoplasm with a poor prognosis. The definitive diagnosis is usually based on the histologic evaluation of the splenectomy specimen. We describe a case of angiosarcoma diagnosed by fine-needle aspiration cytology prior to splenectomy. A 69-year-old white woman presented with heterogeneous lesions in the spleen during a follow-up computed tomographic scan for a history of liposarcoma of the right buttock. A malignant endothelial neoplasm was diagnosed by fine-needle aspiration cytology using immunocytochemistry, and a splenectomy confirmed the presence of angiosarcoma. To our knowledge, this is the first well-documented and confirmed case of primary angiosarcoma of the spleen diagnosed by fine-needle aspiration cytology. This report emphasizes the value of fine-needle aspiration cytology as an important diagnostic tool in splenic neoplasms.

Acute cellular rejection grading scheme for human gastric allografts.

The control of acute cellular rejection (ACR) in multivisceral transplantation improves long-term survival, but monitoring this process can be challenging because different allografts can display varying forms and degrees of rejection. Criteria for ACR of small bowel and liver have been established, but a systematic analysis for ACR in stomach is lacking. For this reason we have developed a comprehensive grading scheme for the evaluation of gastric allograft rejection. The grading scheme was designed to individually grade a variety of changes in the surface epithelium, lamina propria, and glandular structures. The individual values are cumulated, and the final score determines assignment of the rejection grade. The ACR grades range from no evidence of acute cellular rejection to severe rejection. We performed a retrospective study based on 70 gastric allograft biopsies from 20 patients who received multivisceral transplantation from 1995 to 2001. We found that the scoring system showed no significant interobserver variability and allowed for an accurate designation of the ACR grade to the gastric allografts. We found with this grading system that neither clinical symptoms nor gastric endoscopic findings could serve as specific indicators of gastric ACR. Our results also showed that there were differences in the occurrence and intensity of acute rejection between the stomach and other transplanted organs, suggesting that ACR can occur independently among different allografts of the same host. In conclusion, we find that this scheme for grading ACR in gastric transplants is objective and reproducible. This grading system will likely allow for improved correlation between gastric ACR grade and clinical symptoms, as well as improve interobserver uniformity within and between institutions.

Divertículos de la valva anterior mitral como causa de obstrucción del tracto de salida del ventrículo izquierdo

Hombre de 35 años quien consultó por disnea progresiva de 6 meses de evolución. El ecocardiograma transesofágico mostró obstrucción del tracto de salida del ventrículo izquierdo por probable membrana subaórtica. En cirugía se encontraron dos formaciones saculares (divertículos) en la válvula mitral; el mayor de ellos protruía por el tracto de salida del ventrículo izquierdo causando obstrucción. Se practicó extirpación de la válvula con sus divertículos y se colocó prótesis mecánica