Time for a paradigm shift in shared decision-making in trauma and emergency surgery? Results from an international survey

BACKGROUND

Shared decision-making (SDM) between clinicians and patients is one of the pillars of the modern patient-centric philosophy of care. This study aims to explore SDM in the discipline of trauma and emergency surgery, investigating its interpretation as well as the barriers and facilitators for its implementation among surgeons.

METHODS

Grounding on the literature on the topics of the understanding, barriers, and facilitators of SDM in trauma and emergency surgery, a survey was created by a multidisciplinary committee and endorsed by the World Society of Emergency Surgery (WSES). The survey was sent to all 917 WSES members, advertised through the society's website, and shared on the society's Twitter profile.

RESULTS

A total of 650 trauma and emergency surgeons from 71 countries in five continents participated in the initiative. Less than half of the surgeons understood SDM, and 30% still saw the value in exclusively engaging multidisciplinary provider teams without involving the patient. Several barriers to effectively partnering with the patient in the decision-making process were identified, such as the lack of time and the need to concentrate on making medical teams work smoothly.

DISCUSSION

Our investigation underlines how only a minority of trauma and emergency surgeons understand SDM, and perhaps, the value of SDM is not fully accepted in trauma and emergency situations. The inclusion of SDM practices in clinical guidelines may represent the most feasible and advocated solutions.

International comparisons of laboratory values from the 4CE collaborative to predict COVID-19 mortality

Given the growing number of prediction algorithms developed to predict COVID-19 mortality, we evaluated the transportability of a mortality prediction algorithm using a multi-national network of healthcare systems. We predicted COVID-19 mortality using baseline commonly measured laboratory values and standard demographic and clinical covariates across healthcare systems, countries, and continents. Specifically, we trained a Cox regression model with nine measured laboratory test values, standard demographics at admission, and comorbidity burden pre-admission. These models were compared at site, country, and continent level. Of the 39,969 hospitalized patients with COVID-19 (68.6% male), 5717 (14.3%) died. In the Cox model, age, albumin, AST, creatine, CRP, and white blood cell count are most predictive of mortality. The baseline covariates are more predictive of mortality during the early days of COVID-19 hospitalization. Models trained at healthcare systems with larger cohort size largely retain good transportability performance when porting to different sites. The combination of routine laboratory test values at admission along with basic demographic features can predict mortality in patients hospitalized with COVID-19. Importantly, this potentially deployable model differs from prior work by demonstrating not only consistent performance but also reliable transportability across healthcare systems in the US and Europe, highlighting the generalizability of this model and the overall approach.

International Comparisons of Harmonized Laboratory Value Trajectories to Predict Severe COVID-19: Leveraging the 4CE Collaborative Across 342 Hospitals and 6 Countries: A Retrospective Cohort Study

Objectives

To perform an international comparison of the trajectory of laboratory values among hospitalized patients with COVID-19 who develop severe disease and identify optimal timing of laboratory value collection to predict severity across hospitals and regions.

Design

Retrospective cohort study.

Setting

The Consortium for Clinical Characterization of COVID-19 by EHR (4CE), an international multi-site data-sharing collaborative of 342 hospitals in the US and in Europe.

Participants

Patients hospitalized with COVID-19, admitted before or after PCR-confirmed result for SARS-CoV-2.

Primary and secondary outcome measures

Patients were categorized as "ever-severe" or "never-severe" using the validated 4CE severity criteria. Eighteen laboratory tests associated with poor COVID-19-related outcomes were evaluated for predictive accuracy by area under the curve (AUC), compared between the severity categories. Subgroup analysis was performed to validate a subset of laboratory values as predictive of severity against a published algorithm. A subset of laboratory values (CRP, albumin, LDH, neutrophil count, D-dimer, and procalcitonin) was compared between North American and European sites for severity prediction.

Results

Of 36,447 patients with COVID-19, 19,953 (43.7%) were categorized as ever-severe. Most patients (78.7%) were 50 years of age or older and male (60.5%). Longitudinal trajectories of CRP, albumin, LDH, neutrophil count, D-dimer, and procalcitonin showed association with disease severity. Significant differences of laboratory values at admission were found between the two groups. With the exception of D-dimer, predictive discrimination of laboratory values did not improve after admission. Sub-group analysis using age, D-dimer, CRP, and lymphocyte count as predictive of severity at admission showed similar discrimination to a published algorithm (AUC=0.88 and 0.91, respectively). Both models deteriorated in predictive accuracy as the disease progressed. On average, no difference in severity prediction was found between North American and European sites.

Conclusions

Laboratory test values at admission can be used to predict severity in patients with COVID-19. Prediction models show consistency across international sites highlighting the potential generalizability of these models.

Poor patient awareness and frequent misdiagnosis of migraine: findings from a large transcontinental cohort

BACKGROUND AND PURPOSE

Although migraine is the second most disabling condition worldwide, there is poor awareness of it. The objective was to assess the awareness of migraine and previous diagnostic and therapeutic consultations and treatments in a large international population of migraineurs.

METHODS

This was a multicentre study conducted in 12 headache centres in seven countries. Each centre recruited up to 100 patients referred for a first visit and diagnosed with migraine. Subjects were given a structured clinical questionnaire-based interview about the perceptions of the type of headache they suffered from, its cause, previous diagnoses, investigations and treatments.

RESULTS

In all, 1161 patients completed the study. Twenty-eight per cent of participants were aware that they suffered from migraine. Sixty-four per cent called their migraine 'headache'; less commonly they used terms such as 'cervical pain' (4%), tension headache (3%) and sinusitis (1%). Eight per cent of general practitioners and 35% of specialists (of whom 51% were neurologists and/or headache specialists) consulted for migraine formulated the correct diagnosis. Before participating in the study, 50% of patients had undergone X-ray, computed tomography and/or magnetic resonance imaging of the cervical spine and 76% underwent brain and/or cervical spine imaging for migraine. Twenty-eight per cent of patients had received symptomatic migraine-specific medications and 29% at least one migraine preventive medication.

CONCLUSIONS

Although migraine is a very common disease, poor awareness of it amongst patients and physicians is still an issue in several countries. This highlights the importance of the promotion of migraine awareness to reduce its burden and limit direct and indirect costs and the risk of exposure to useless investigations.

Morphological analysis of ischemia-reperfusion injury in a cold ischemia model of jejunal free flap for hypopharyngeal reconstruction

BACKGROUND

Jejunal free flap (JFF) reconstruction is a popular treatment option for advanced hypopharyngeal cancer. Several factors including ischemia-reperfusion injury (IRI) can cause mucosal damage and progressive flap necrosis. We investigated the development and time-related progression of morphological and cellular changes in patients with JFF reconstruction including cold preservation of the graft.

METHODS

Eleven patients were enrolled. Biopsies were taken during surgery from normally perfused tissue, before loop isolation (T0), at the end of back-table surgery (T1), immediately before reperfusion (T2), 15' after reperfusion (T3), and at the end of the digestive anastomoses (T4) and from the external monitor daily from the 1st to the 5th postoperative day (M1-M5). Histomorphological and immunohistochemical parameters in the intraoperative and postoperative samples were evaluated and compared.

RESULTS

Delayed flap necrosis was observed in 2 patients. The cold ischemia phase did not negatively affect mucosal regeneration after reperfusion; morphological and cellular damage parameters returned to normal by the end of surgery or along the early postoperative period. Significant enterocyte replication activity was observed at the end of revascularization, which continued in the postoperative phase, leading to recovery of the epithelial morphological integrity and disappearance of apoptotic cells. An inflammatory infiltrate persisted in the M samples, and in a significant proportion of samples, mucosal fibrosis developed by the end of the postoperative observation.

CONCLUSION

Cold perfusion and preservation of the JFF can effectively limit the negative effects of IRI and to prevent short- and medium-term complications that can compromise the final outcome.

Abstract 812: New c-KIT mutations in GISTs: Bad for good

Gastrointestinal stromal tumors are mesenchymal tumors arising in the stomach and small bowel and more rarely in the rectum, esophagus, peritoneum and retroperitoneum. These tumors are characterized by KIT or PDGFRA mutations. KIT mutations are all in frame and lead to constitutive tyrosine kinase domain activation without ligand binding. Mutations concern four exons (9, 11, 13 and 17) but mainly exon 11.

In this work we report a case of a GIST patient with wild-type PDGFRA but bearing two mutations in KIT exon 9, i.e., the insertion mutation Y503_F504insAY and the missense mutation K509N.

The patient was treated with Imatinib at standard regimen dose (400 mg/day), and responded well.

Accordingly, in silico experiments were performed to disclose the effects exerted by these new mutations on the protein structure, its thermodynamic stability, and the ability to promote/interfere with Imatinib binding.

Direct drug binding thermodynamics and kinetics of the mutant KIT were measured using isothermal titration calorimetry. FInally, in vitro kinase assays were performed to monitor the phosphorylation status of this new mutant KIT.

The prototypical KIT mutations Δ559 and T670I were also analyzed in parallel for comparison.

To our knowledge, only AY 502-503 duplication/insertion and K509I substitution have been previously reported.

Citation Format: Erik Laurini, Suzana Aulic, Domenico Marson, Maurizio Fermeglia, Roberta Riboni, Marco Lucioni, Elena Dellera, Mario Alessiani, Vittorio Perfetti, Sabrina Pricl. New c-KIT mutations in GISTs: Bad for good [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 812.

Influence of Surgical Technique, Performance Status, and Peritonitis Exposure on Surgical Site Infection in Acute Complicated Diverticulitis: A Matched Case-Control Study

BACKGROUND

Acute generalized peritonitis secondary to complicated diverticulitis is a life-threatening condition; the standard treatment is surgery. Despite advances in peri-operative care, this condition is accompanied by a high peri-operative complication rate (22%-25%). No definitive evidence is available to recommend a preferred surgical technique in patients with Hinchey stage III/IV disease.

METHODS

A matched case-control study enrolling patients from four surgical units at Italian university hospital was planned to assess the most appropriate surgical treatment on the basis of patient performance status and peritonitis exposure, with the aim of minimizing the surgical site infection (SSI). A series of 1,175 patients undergoing surgery for Hinchey III/IV peritonitis in 2003-2013 were analyzed. Cases (n=145) were selected from among those patients who developed an SSI.

THE CASE

control ratio was 1:3. Cases and control groups were matched by age, gender, body mass index, and Hinchey grade. We considered three surgical techniques: T1=Hartman's procedure; T2=sigmoid resection, anastomosis, and ileostomy; and T3=sigmoid resection and anastomosis. Six scoring systems were analyzed to assess performance status; subsequently, patients were divided into low, mild, and high risk (LR, MR, HR) according to the system producing the highest area under the curve. We classified peritonitis exposition as P1=<12 h; P2=12-24 h; P3=>24 h. Univariable and multivariable analyses were performed.

RESULTS

The Apgar scoring system defined the risk groups according to performance status. Lowest SSI risk was expected when applying T3 in P1 (OR=0.22), P2 (OR=0.5) for LR and in P1 (OR=0.63) for MR; T2 in P2 (OR=0.5) in LR and in P1 (OR=0.61) in MR; T1 in P3 (OR=0.56) in LR; in P2 (OR=0.63) and P3 (OR=0.54) in MR patients, and in each P subgroup (OR=0.93;0.97;1.01) in HR.

CONCLUSIONS

Pre-operative assessment based on Apgar scoring system integrated with peritonitis exposure in complicated diverticulitis may offer a ready-to-use tool for reducing SSI-related complications and applying appropriate treatment, reducing the need for disabling ostomy.

Peritonitis secondary to spontaneous perforation of a primary gastrointestinal stromal tumour of the small intestine: A case report and a literature review

•

Emergency presentation of a GIST is not uncommon and one of its manifestations is acute abdome.

•

The cases described in the literature are the tip of the iceberg and spontaneous rupture or perforation of GISTs are a far more frequent first presentation of this rare tumour.

•

The jejunum was the more common location of perforation compared to the ileum.

•

Emergency surgery is mandatory and should achieve radical resection.

Introduction

A few cases of acute abdomen caused by perforation of small-intestinal gastrointestinal stromal tumours (GISTs) have been reported in the literature.

Presentation of case

Together with a review of the published cases, here we report a case of an elderly patient with peritonitis due to spontaneous perforation of a GIST of the jejunum. An 82-year-old man was admitted to the emergency unit of our hospital with fever and severe abdominal pain. An abdominal enhanced computed tomography scan detected a 6 cm solid mass in the left upper quadrant adherent to a jejunal loop and surrounded by free fluid and free air. Due to the radiological features of the mass, the diagnosis of a perforation of a GIST arising from the jejunum wall was suspected. The patient underwent emergency laparotomy. Intraoperative findings confirmed diffuse peritonitis secondary to jejunal tumour perforation. A segmental resection of the jejunum containing the mass was performed followed by a mechanical end-to-side anastomosis. The histopathologic examination of the mass confirmed the diagnosis of a perforated GIST of the small intestine (high-risk category). The post-operative course was uneventful and the patient was treated with adjuvant imatinib therapy.

Discussion

Twenty-one other cases of spontaneous perforation of small intestine GISTs are reported in the literature and are summarized in the present review.

Conclusion

The described case is the tip of the iceberg and spontaneous rupture or perforation of GISTs are a far more frequent first presentation of this rare tumour.

The challenge of extraabdominal desmoid tumour management in patients with Gardner's syndrome: radiofrequency ablation, a promising option

Desmoid tumours are benign, myofibroblastic stromal neoplasms common in Gardner’s syndrome, which is a subtype of familial adenomatous polyposis characterized by colonic polyps, osteomas, thyroid cancer, epidermoid cysts, fibromas and sebaceous cysts. The primary treatment is surgery, followed by adjuvant radiotherapy, but the local recurrence rate is high, and wide resection can result in debilitating loss of function. We report the case of a 39-year-old man with Gardner’s syndrome who had already undergone a total prophylactic colectomy. He developed desmoid tumours localized in the mesenteric root, abdominal wall and dorsal region, which were treated from 2003 through 2013 with several surgical procedures and percutaneous radiofrequency ablation. In 2008 and 2013, RFA was applied under ultrasonographic guidance to two desmoid tumours localized in the dorsal thoracic wall. The outcomes were low-grade pain and one case of superficial skin necrosis, but so far there has been no recurrence of desmoid tumours in these locations. Surgical resection remains the first-line therapy for patients with desmoid tumours, but wide resection may lead to a poor quality of life. Radiofrequency ablation is less invasive and expensive and is a possible therapeutic option for desmoid tumours in patients with Gardner’s syndrome.

The "Pavia model" of experimental small bowel transplantation in pigs: technical variations for ischemia reperfusion injury studies

Ischemia reperfusion injury (IRI) is a major field of study in small bowel transplantation because of its implications regarding intestinal immunity. In this study, we have introduced some variations to the described models of IRI in pigs to make possible a complete isolation of the small bowel for IRI studies. In swine, two anatomical barriers make impossible a complete isolation of the small bowel at the origin of superior mesenteric artery (SMA) and vein (SMV): the main colic vessels, which originate distally to form SMA and SMV, and the blood supply of the distal portion of the duodenum and the cephalic part of the pancreas. In a group of Large White pigs (n = 5), we have performed a complete isolation of the small bowel, including sub-total colectomy and pancreaticoduodenectomy. Both SMA and SMV were isolated at the origin from the aorta and at the junction of the splenic vein, respectively. Intestinal continuity was restored with duodenojejunal anastomosis and with ileotransverse colon anastomosis. One pig died on postoperative day 5 from intestinal occlusion due to adhesions. The remaining four pigs were killed on postoperative day 7 after an uneventful postoperative course. No complications were found at autopsy. In swine, resection of part of the pancreas and duodenum and removal of the large bowel does not affect short-term survival, allowing a full isolation of the entire small bowel mimicking the transplantation procedure. Thus, this model appears to be attractive for IRI studies in the field of intestinal transplantation.

Successful non-operative management of spontaneous type II gallbladder perforation in a patient with Alzheimer's disease

A 77-year-old man with Alzheimer's disease was admitted to a rural hospital in June 2012 and an acute cholecistytis was first diagnosed. Surgery was not considered as a possible option due to the critical condition of the patient and his severe comorbidities. After 2 days of broad-spectrum antibiotics, the patient worsened and developed severe sepsis. A gallbladder perforation with intrahepatic abscess formation was diagnosed on ultrasonography (US) and abdominal CT scan. The patient underwent percutaneous US-guided gallbladder drainage with resolution of the sepsis and rapid clinical improvement. After 1 month, the drainage was removed and the patient was discharged. He survived in good condition for 18 months and he passed away from pneumonitis in December 2013. This case shows that in a case of acute cholecystitis with gallbladder perforation, percutaneous gallbladder drainage can be a lifesaving procedure in elderly patients with severe comorbidities (including Alzheimer's disease) who are not candidates for elective surgery.

Impaired intrahepatic natural killer cell cytotoxic function in chronic hepatitis C virus infection

Hepatitis C virus (HCV) persistence in the host results from inefficiencies of innate and adaptive immune responses. Most studies addressing the role of innate immunity concentrated on peripheral blood (PB) natural killer (NK) cells, whereas only limited information is available on intrahepatic (IH) NK cells. We therefore examined phenotypic and functional features of IH and PB NK cells in paired liver biopsy and venous blood samples from 70 patients with chronic HCV infection and 26 control persons subjected to cholecystectomy for gallstones as controls. Ex vivo isolated IH NK cells from HCV-infected patients displayed unique phenotypic features, including increased expression of NKp46-activating receptor in the face of reduced tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and cluster of differentiation (CD) 107a expression, which resulted in impaired degranulation compared with controls. To gain insights into the effect of HCV on NK cells, we exposed peripheral blood mononuclear cells (PBMCs) from patients and healthy donors to cell-culture-derived HCV (HCVcc) and measured NK cell degranulation, TRAIL, and phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) expression. Exposure of PBMCs to HCVcc significantly boosted NK degranulation, pERK1/2, and TRAIL expression in healthy donors, but not in patients with chronic HCV infection, a defect that was completely reversed by interferon-alpha. Purified NK cells showed a minimal, though significant, increase in degranulation and TRAIL expression, both in patients and controls, after exposure to HCVcc.

CONCLUSIONS

These findings indicate dysfunctional IH NK cell cytotoxicity associated with TRAIL down-regulation in chronic HCV infection, which may contribute to virus persistence. PB NK cell impairment upon exposure to HCVcc suggests the existence of an accessory cell-dependent NK cell lytic defect in chronic HCV infection predominantly involving the TRAIL pathway.

Immunomodulatory properties of porcine, bone marrow-derived multipotent mesenchymal stromal cells and comparison with their human counterpart

Thanks to their immunonodulatory properties, multipotent mesenchymal stromal cells (MSCs) are a promising strategy for preventing/reducing the risk of graft rejection after hematopoietic cell and solid organ transplantation. We have previously demonstrated that porcine MSCs (pMSCs) can be isolated from bone marrow and display similar morphology and differentiative capacity as compared to human MSC (hMSCs). In this study, we investigated the in vitro immunomodulatory properties (namely the ability to suppress lymphocyte proliferation in response to phytohemagglutinin and the cytokine production in the culture supernatants) of pMSCs from six Large White 6-month old piglets. Similarly to hMSCs, pMSCs reduced the phytohemagglutinin-induced lymphocyte proliferation. High levels of IL-6 were found in culture supernatants, whereas IL-10 and TGF-β were not detectable. In conclusion, ex vivo expanded pMSCs share selected biological/functional properties with hMSCs. pMSCs may be used in in vivo models to investigate novel approaches of prevention of graft rejection in solid organ transplantation.

Skin and kidney histological changes in graft-versus-host disease (GVHD) after kidney transplantation

Kidney transplantation (Ktx) is generally performed during end stage renal disease due to a loss of the kidneys' ability to filter wastes from the circulatory system. Acute graft-versus-host disease (GVHD) after Ktx is a life-threatening complication that progresses to organ failure, systemic complications, and death. The current study evaluated the significance of histologic findings of GVHD as obtained from skin biopsies following Ktx in swine. A swine model of Ktx with tacrolimus-based immunosuppression was used to assess possible correlations between acute-graft-cellular rejection and skin histological findings for prediction of GVHD. Animals were divided into a Ktx treatment group or a control group with no Ktx and skin and kidney biopsies were histologically assessed at postoperative days 0, 15, 30, 45 and 60. Skin samples were analyzed and classified from grade 1 to 4 of skin GVHD and the major histopathological changes of kidney acute cellular rejection were described using Banff's score system. We observed a significant linear correlation between the histological grading values of skin biopsy changes and the histological grading values of kidney biopsies (Kendall's tau_b=0.993) in the Ktx experimental group. No histological changes were observed in controls. Our findings demonstrate the diagnostic value of staging skin GVHD after Ktx and suggest it's future utility for monitoring long term Ktx-induced changes.

Robotic-assisted laparoscopic donor nephrectomy with transvaginal extraction of the kidney

Transvaginal recovery of the kidney has recently been reported, in a donor who had previously undergone a hysterectomy, as a less-invasive approach to perform laparoscopic live-donor nephrectomy. Also, robotic-assisted laparoscopic kidney donation was suggested to enhance the surgeon's skills during renal dissection and to facilitate, in a different setting, the closure of the vaginal wall after a colpotomy. We report here the technique used for the first case of robotic-assisted laparoscopic live-donor nephrectomy with transvaginal extraction of the graft in a patient with the uterus in place. The procedure was carried out by a multidisciplinary team, including a gynecologist. Total operative time was 215 min with a robotic time of 95 min. Warm ischemia time was 3 min and 15 s. The kidney was pre-entrapped in a bag and extracted transvaginally. There was no intra- or postoperative complication. No infection was seen in the donor or in the recipient. The donor did not require postoperative analgesia and was discharged from the hospital 24 h after surgery. Our initial experience with the combination of robotic surgery and transvaginal extraction of the donated kidney appears to open a new opportunity to further minimize the trauma to selected donors.

Isolation and ex vivo expansion of bone marrow-derived porcine mesenchymal stromal cells: potential for application in an experimental model of solid organ transplantation in large animals

Pharmacological aspecific immunosuppression, despite being widely used in solid organ transplantation recipients, is unable to completely prevent allograft rejection. It promotes the occurrence of sometimes life-threatening infections. Due to their immunosuppressive and anti- inflammatory properties, there is great interest in the therapeutic use of bone marrow (BM)-derived mesenchymal stromal cells (MSC). Large animal models play a crucial role to investigate the biological and functional properties of MSCs as novel cellular therapy. In the current study we sought to isolate expand ex vivo, and phenotypically characterize MSC derived from BM of 4 Large White 6-month-old piglets. Porcine MSC (pMSC) were characterized for their in vitro differentiation capacity. pMSC were successfully isolated from all BM samples. They showed spindle-shaped morphology and a stable doubling time on culture. They were positive for CD90, CD29, CD105, and negative for CD45 and CD11b. Furthermore, they differentiated, upon specific in vitro conditions toward adipogenic and osteogenic lineages. The optimization of methods for the isolation and characterization of pMSC may be useful to elucidate their biological and functional properties. The anatomy and physiology of the pig, which is similar to humans, make this animal model more attractive than small animals to test the safety and efficacy of MSC in the context of solid organ transplantation.

Mesenchymal stem cells infusion prevents acute cellular rejection in rat kidney transplantation

Mesenchymal stem cells (MSC) are multipotent cells that differentiate into various mature cell lineages. MSC show immunomodulatory effects by inhibiting T-cell proliferation. We evaluated the effect of the infusion of MSC in rats experimental kidney transplantation. Sprague-Dawley transgenic rats (SD) able to express the green fluorescent protein (EGFP) were used as MSC donors. Syngeneic (Lewis to Lewis, n = 10) and allogeneic (Fischer to Lewis, n = 10) kidney transplantations were performed after bilateral nephrectomy. Five transplanted rats who received syngeneic grafts, were treated with 3 x 10(6) MSC (Gr B), while the other 5 did not received MSC (Gr A). Five rats with allogenic grafts received 3 x 10(6) MSC (Gr C) and another 5 did not receive MSC (Gr D). The MSC were infused directly into the renal artery of the graft. No immunosuppressive therapy was provided. The animals were killed after 7 days. Biochemical analysis for renal function, histological (Banff criteria) and immunohistological analysis (ED1+ and CD8+) were performed on treated animals. MSC improved kidney function in Gr B and D vs Gr A and C. The tubular damage appeared to be less severe among Gr B and Gr D with respect to Gr A and C (P < .01). Vasculitis was more accentuated in Gr A and C (P < .01). MSCs reduced the inflammatory infiltrate; in Gr B and D, the number of ED1+ cells was lower than in Gr A and C (P < .005), which was also observed for CD8+ cells (P < .05). Our study demonstrated that the infusion of MSC attenuated histological damage from acute rejection by reducing the cellular infiltration.

Which is the most suitable and effective route of administration for mesenchymal stem cell-based immunomodulation therapy in experimental kidney transplantation: endovenous or arterial?

Immunomodulating cell therapy represents a new perspective for the control of cellular immune responses that determine the occurrence of acute rejection (ACR) in allo-transplantation. Mesenchymal stem cells (MSC) demonstrate immunoregulatory effects by inactivating T-cell components that regulate tissue damage in transplantation models. The presumed mechanism of action is recruitment of cells by a cytokine network. The purpose of this study was to test which route of administration (intra-arterial vs intravenous) was the most effective route to achieve immunomodulating effects in experimental rat kidney transplantation. Transgenic Sprague-Dawley rats (SD) expressing the enhanced green fluorescent protein (EGFP) at the somatic level were used as MSC donors: Allogeneic Fischer to Lewis grafts (n = 4 per group) were performed in rats after bilateral nephrectomy. In Gr B, 3 x 10(6) MSCs were infused into the renal graft artery, whereas in Gr C, they were infused into the tail vein. The untreated Gr A were a control group. No immunosuppressive therapy was administered. The animals were sacrificed at day 7 postoperatively. Biochemical analysis for renal function, histological (Banff criteria) and immunohistological (anti-EGFP-Immunoglobulin) analysis were performed on the transplanted animals. In Gr B, functional recovery was more rapid (creatinine: Gr B vs Gr C, P < .05). The inflammatory infiltrate in the graft was less in Gr B vs Gr C, with preservation of tubules, arteries, and glomeruli (P < .01). Intra-arterial infusion of MSCs was more effective to control ACR.

A novel technique for rat liver transplantation using Quick Linker system: a preliminary result

BACKGROUND

The clinical success of liver transplantation is founded upon years of experimental research. Since Kamada and colleagues developed the "two-cuff" technique, the rat has become the best model for extensive investigations. Although the Kamada technique is technically complex and not easy to master, it is still the mainstay of orthotopic liver transplantation in rodents. We have developed a modified three-cuff version of this technique that facilitates anastomosis and markedly reduces warm ischemia time.

MATERIALS AND METHODS

The new technique involves a set of five microinstruments (the Quick-Linker system) designed and manufactured by our group. It was tested in male Lewis rats (group 1, donors n = 10, recipients n = 10). The graft was explanted as usual and standard cuffs were attached to the portal vein and the supra- and infrahepatic vena cavae. Corresponding vessels in the recipient were isolated, and Quicker-Linker holding rings were attached to each. The vessels were then clamped and the native organ removed. Once the graft was positioned in the recipient's abdomen, the holding rings attached to the recipient vessels and the cuffs applied to graft vessels were automatically aligned and joined with the aid of a special alignment tool.

RESULTS

Warm ischemia times were always inferior to 6 minutes. Survival at postoperative day 10 was 80%. Liver function was well preserved in all of the surviving rats.

CONCLUSIONS

The Quick-Linker technique significantly shortens warm ischemia time and allows rapid anastomosis that is relatively independent of operator skill. It can be considered a reliable option for microsurgeons looking for quick results and high success rates.

Reconstruction of the hypopharynx after free jejunum flap failure: Is a second free jejunum transfer feasible?

Reconstruction after circumferential pharyngolaryngectomy is a challenging problem. Reconstruction methods should ensure an appropriate mucosa lining of the digestive tract, preferably already tubulized, and peristalsis. Despite the high reported success rates, the jejunum flap is still occasionally lost due to thrombosis of the pedicle and/or fistula formation. Five cases of circumferential pharyngolaryngectomy in which failure of the jejunum loop was managed with a second free or pedicle flap are presented. A second free jejunum was reliable in selected patients, depending on time of detection of flap necrosis, on bacterial control of the wound and on the vascular or general conditions. For this reason, careful monitoring of the flap and clinical signs of necrosis in the first 5 post-operative days is crucial to prevent the formation of fistulas and infection and to increase the possibility of using this kind of salvage surgery. Pedicle flaps should be used only in the event of severe complications because of their high risk of post-operative salivary fistulas.

Skin biopsies predict acute graft-versus-host disease after small bowel transplantation in pigs

Intestinal transplantation is being increasingly performed to treat patients with irreversible intestinal failure. The major cause of intestinal graft failure is graft-versus-host disease (GVHD) that represents a life-threatening complication after small bowel transplantation (Itx). The purpose of this study was to assess the diagnostic and prognostic value of skin biopsy histological changes for acute GVHD after Itx in pigs. Thirty-four Large White pigs were divided into three groups: Group 1 with Itx only, Group 2 with Itx and donor bone marrow infusion (Itx BM) and Group 3 (control group - before the operation). Animals received tacrolimus-based immunosuppression from day 0 to day 30 postoperatively. Skin and small bowel biopsies were histologically assessed, analysed and classified from grade 1 to 4 on postoperative days 15, 30, 45 and 60. There was a strong correlation between the histological grading values of skin biopsy changes and the histological grading values of small bowel biopsy changes (Kendall's tau_b is 0.855 for the Itx group and 0.730 for the Itx BM group). The significant correlation found between skin and small bowel histological changes suggests the prognostic value of skin biopsies after Itx. In conclusion, our findings emphasise the diagnostic and prognostic value of skin biopsy analysis for acute GVHD after Itx.

Prognostic value of skin histology in GVHD after intestinal transplantation

Intestinal transplantation (Itx) is increasingly being performed to treat patients with irreversible intestinal failure. Acute graft-versus-host disease (GVHD) after Itx is a life-threatening complication which can progress to organ failure, systemic complications and death. The purpose of this study was to assess the diagnostic and prognostic role of histological changes as demonstrated by skin biopsy for acute GVHD after Itx. A porcine model of orthotropic Itx and bone marrow transplantation with tacrolimus-based immunosuppression was used to assess any correlation between acute graft cellular rejection and skin histological findings for the prediction of GVHD. Skin and small intestinal biopsies were histologically assessed on postoperative days 0, 15, 30, 45, and 60 and analyzed and classified as grade 1 to 4. A linear correlation was observed between the histological grading values of skin biopsy changes and the histological grading values of small intestinal biopsy changes (Kendall's tau_b was 0.855 for the Itx group and 0.730 for the Itx BM group. In conclusion, our findings emphasize the diagnostic and prognostic value of skin biopsy analysis for acute GVHD after Itx.

Elemental enteral nutrition preserves the mucosal barrier and improves the trophism of the villi after small bowel transplantation in piglets

The main goals for a successful small bowel transplantation (SBTx) are the control of acute rejection and maintenance of the mucosal barrier, which plays a key role in preventing bacterial translocation and preserving absorptive capacity. According to recent evidence that sustaining enteral nutrition (EN) as rehabilitative therapy improves the integrity of the mucosal barrier after SBTx, we studied the trophic effect of a new elemental enteral solution whose proteinic supply is represented by oligomeric-aminoacidic chains. In a swine SBTx model we studied three groups, divided by the different postoperative feeding: group 1 (n = 5): standard swine chow, group 2 (n = 5): polymeric enteral solution, group 3 (n = 5): elemental enteral solution (Peptamen, Nestlè Corp). All animals were immunosuppressed with a tacrolimus/FK778 combined oral therapy. The nutritional indices evaluated were: body weight, episodes of diarrhea, D-xylose absorption test, and histopatological and villi morphometric analysis. Three pigs died before the end of the study, two in group 1 (pneumonia and sepsis), one in group 2 (pneumonia). Mean days of diarrhea were 15, 10, and 3 in groups 1, 2, and 3, respectively (P < .05). The final/starting weight ratio was 1.08 for group 3 and 0.92 for group 2 (P < .05); the D-xylose curves showed a statistically significant difference for group 3 versus the groups 2 and 1 (P < .05), as well as for the villi height (P < .01) and width (P < .05). In conclusion, elemental enteral solution, with its basic protein supply, does not require a very complex enzymatic system to be metabolized. Thus, it may contribute to a faster recovery of the mucosal barrier and to limit the hypercatabolic state.

Prolonged Survival With FK778 (Malononitrilamide) Monotherapy After Small Bowel Transplantation: A Large Animal Study

Malononitrilamide 715 (FK778) is a new class of immunosuppressant, derived from the active metabolite of leflunomide A77 1726. We investigated the efficacy of two different immunosuppressive induction protocols with tacrolimus plus FK778 followed by FK778 monotherapy. In a swine model of small bowel transplantation, we observed three groups, divided by different therapy regimens: group 1 (n = 5): no immunosuppressant (control group); group 2 (n = 10): oral tacrolimus (from postoperative day [POD] 0 to 30) and FK778 (from POD 0 to 60); group 3 (n = 8): oral tacrolimus, as group 2, and FK778 (from POD 7 to POD 60). Median survival was 11, 60, and 21 days in groups 1, 2, and 3, respectively. In group 1 all animals died of acute rejection; in group 2 the causes of death were technical complication (n = 1) and sepsis (n = 1); in group 3, one animal died from obstruction, two from pneumonia, one from peritonitis, one from sepsis. Group 2 accounted for 0.5 infection episode/animal versus 0.62 in group 3 (P < .05). Acute rejection was absent or mild in 66% and 75% of group 3 and 2 biopsies, respectively (P < .05). The D-xylose absorption curves from groups 2 and 3 were similar to those of the nontransplanted healthy animals. In conclusion, FK778 monotherapy after a consistent induction period with tacrolimus combined immunosuppression is able to extend survival and preserve optimal absorptive capacity of the small bowel allograft in our pig model. The association of tacrolimus and FK778 from day 1, compared to the delayed administration of FK778 from day 7, results in a significant reduction of infections and postoperative complications.

Atypical reconstructions with free jejunum flap after circumferential pharyngolaryngectomy

The ideal reconstruction after circumferential pharyngolaryngectomy is represented by the jejunum free flap, but when the resection extends to the oro- or nasopharynx, the discrepancy between the lumen of the flap and the pharyngeal defect represents a disadvantage. Two reconstructions to overcome this problem are presented: end-to-side anastomosis between the pharynx and the antimesenteric side of the jejunum; and a jejunal "reservoir." The type 1 technique is quicker to perform, but can result in dysphagia; the type 2 technique is more complex, but usually no dysphagia is observed. In our opinion, no ideal surgical technique exists to equal the jejunum loop. The choice must be tailored to the single patient, bearing in mind the degree of the defect, the stage of the tumor removed, the general conditions of the patient, and personal surgical experience. Whatever procedure is chosen, it should provide the best possible quality of life for the expected life span of the patient.

Incidence of graft rejection in small bowel transplanted pigs after immunosuppression withdrawal

As intestinal grafts require heavy immunosuppression, there are no reports of immunosuppression withdrawal after clinical small bowel transplantation. In this large-animal study, we investigated the occurrence of graft rejection in intestinal-transplanted pigs after withdrawal. Large-White unrelated piglets were transplanted and divided in three groups: group 1 (n = 5), intestinal transplantation (ITx) with no immunosuppression; group 2 (n = 7), Itx and 60 days of treatment with tacrolimus and mycophenolate mofetil; group 3 (n = 5), Itx and donor bone marrow infusion (DBMi) and 60 days of treatment with tacrolimus and mycophenolate mofetil. Follow-up time after withdrawal was 120 days. Group 1 pigs died of graft acute cellular rejection (ACR) after a median of 11 days. In group 2, two pigs died of ACR-related infection and another two of ACR within 90 days. The remaining three animals (43%) were sacrificed at day 180, and their grafts showed no signs of ACR. In group 3, two pigs died of ACR-related infection and one of graft versus host disease within 80 days; at day 180 the two surviving animals showed signs of chronic rejection in the allograft. This study demonstrates that total withdrawal after ITx is followed by sudden and lethal ACR (or ACR-related infection) in more than 50% of the recipients. When a tolerance-inducing strategy as DBMi is applied, lethal graft versus host disease may also occur. In group 3, the intestinal allograft, to which the recipients were partially tolerant, developed chronic rejection that was probably associated with a decline with time of donor-leukocytes chimerism, as recently demonstrated in rats.

Early outcome of different steroid-free regimens in small bowel transplantation: a large-animal study

The intestine is a highly immunogenic organ that requires heavy immunosuppression (IS); therefore corticosteroid withdrawal after clinical small bowel transplantation (SBT) has not been standardized. In this study, we compared different immunosuppressive regimens (none with steroid or induction treatment) in a SBT pig model. Large White unrelated piglets were transplanted and divided into four groups as follow: group 1 (n = 3): no IS; group 2 (n = 10): IS with tacrolimus only; group 3 (n = 10): IS with tacrolimus and mycophenolate mofetil; group 4 (n = 5): IS with tacrolimus and rapamycin. Follow-up time was 30 days. All IS drugs were given orally; tacrolimus whole blood levels ranged between 5 and 15 ng/mL in all groups except for group 2 whose tacrolimus whole blood levels ranged between 15 and 25 ng/mL. Group 1 pigs died of graft acute rejection (ACR) after a median of 12 days. Overall survival in groups 2, 3, and 4 at day 30 was 40%, 80%, and 60%, respectively. Biochemical parameters, including glycemia and cholesterol, were into the normal range with no significant differences between groups. At the end of the study, one animal in group 2 and another one in group 4 showed histological signs of moderate to severe ACR. The incidence of infection was higher in group 2 (2.1 episodes/pig) compared to group 3 (1.25) and group 4 (1.6). This large-animal study demonstrates that tacrolimus-based IS without corticosteroids allows, in the early postoperative period (30 days) after SBT, good survival rates without an increased risk in the incidence of rejection.

FK778 does not impair intestinal allograft absorption in a preclinical model of total small bowel transplantation

Malononitrilamide 715 (FK778), a new low-molecular weight immunosuppressant, inhibits both T-cell and B-cell function by acting on the pathway for de novo pyrimidine biosynthesis. Pyrimidines are important for intestinal trophism; their inhibition may predispose to metabolic and functional impairments, such as diarrhea and malabsorption. In this study we assessed the absorptive capacity of intestinal allografts in a large-animal model of small bowel transplantation (SBTx) in pigs chronically treated with FK778. Ten outbred pigs underwent total orthotopic SBTx. Immunosuppression consisted of oral tacrolimus (trough levels 5-15 ng/mL) and oral FK778 (4 mg/kg per day) administered for 60 days. The D-xylose absorption test was performed at day 60 to evaluate carbohydrate absorption. Results were compared to normal controls. Eight of the 10 animals were alive and in good condition at day 60. All of their allografts were free of rejection. The animals had a mean maximal weight loss of 6.4% during the study period; the final weight was comparable to the initial weight (P > .05). Diarrhea was present in all animals (mean 16% of postoperative days). The D-xylose curves showed that absorption in the transplanted animals at day 60 was similar to that in the untreated controls (P > .05). The absence of differences was confirmed by the statistical analysis. In conclusion, our preclinical study in pigs showed that chronic treatment with FK778 in combination with tacrolimus did not impair carbohydrate absorption by the allograft after SBTx.

FK778 and Tacrolimus Combination Therapy to Control Acute Rejection After Pig Intestinal Transplantation

Malononitrilamide 715 (FK778) is a new class of low molecular weight immunosuppressant. Experimental studies in heart, liver, and kidney transplantation have shown a strong synergism when FK778 is used in combination with tacrolimus and when its administration is delayed by 7 days after the transplant. Following this indication, in a swine model of orthotopic small bowel transplantation (SBT), we assessed the efficacy of combined low dose tacrolimus and FK778 administered from day 0 or day 7. The entire small bowel was replaced in 16 piglets: group 1 (n = 5), no immunosuppression; group 2 (n = 6) oral tacrolimus to maintain whole blood trough levels between 5 and 15 ng/mL plus FK778 4 mg/kg per day; group 3 (n = 6) oral tacrolimus as in group 2 plus FK778 4 mg/kg per day administered after a 7-day delay posttransplant. The median survival was 8 days in group 1, 60 days in group 2, and 13 days in group 3. The differences between group 2 and 1 and between group 2 and 3 are statistically significant. Three episodes of major bacterial infection were detected in both group 2 and 3 (0.5 episode/animal). The infectious-related mortality was 0% in group 2 and 50% in group 3 (P < .05). Acute cellular rejection was absent or mild in all group 2 and 3 stomal biopsies. In conclusion, combining tacrolimus and FK778 allowed prolonged survival after SBT in swine when FK778 was started at the time of SBT. The delayed administration of FK778 resulted in a high incidence of lethal infectious complications.

[Laparoscopic harvest of the jejunal free flap for cervical esophageal reconstruction]

The jejunal free flap is a standard technique in the reconstruction of hypopharyngeal and cervical esophageal defects. Conventional harvesting of the jejunal segment is performed with midline open laparotomy, which is associated with complications including prolonged ileus, abdominal pain, wound infection or dehiscence. Laparoscopic resection of the small intestine is a well documented surgical technique. Two different methods of laparoscopic harvest of a jejunal autografts for their cervical implantation have been already described. In both cases, low complication rate and better postoperative course have been observed in the patients treated. During the last 10 years, we have performed 43 circumferential pharyngoesophageal resection for advanced hypo-pharyngeal cancer followed by reconstruction with a free flap of jejunum. All but one the jejunal segments have been harvested with conventional open laparotomy. In the last patient of this group, laparoscopic harvest of the jejunal segment has been successfully performed. In this paper, we describe the laparoscopic technique used and we compare the postoperative course of this patient with those of the patients treated with conventional technique.

Abdominal spilled stones: ultrasound findings

Laparoscopic cholecystectomy (LC) is the treatment of choice for uncomplicated symptomatic gallstones. Spillage of stones due to gallbladder rupture has been reported in up to 33% of all LCs, but clinical sequelae caused by dropped gallstones are uncommon. We recently observed two patients with retained stones after LC. Correct diagnosis was made by abdominal ultrasonography (US) in both cases. In the first patient, who presented with fever, malaise, and weight loss 18 months after LC, abdominal US revealed hypoechoic focal lesions containing hyperechoic images with posterior shadowing of the liver and spleen. US-guided aspiration biopsies of these lesions yielded purulent material, and the injection and aspiration of saline solution provoked rolling movements of the hyperechoic images. Laparotomy confirmed the diagnosis of abscess-containing spilled gallstones. In the second patient, multiple hyperechoic images with posterior shadowing were observed in the Morison pouch during a routine US examination. The diagnosis of retained stones was consistent with the history of gallstone spillage during LC performed 2 months previously and was confirmed by computed tomographic findings of hyperdense images in the Morison pouch. The patient was asymptomatic, and treatment was thus deferred. Our experience suggests that US can be very useful in the detection of gallstones spilled during LC.

Assessment of an LC-MS method for plasma quantification of the new immunosuppressant FK778 through comparison with HPLC-UV

FK778 is a new immunosuppressive agent, derived from the leflunomide-active metabolite A77 1726. It inhibits de novo pyrimidine nucleotide synthesis showing efficacy in the prevention and treatment of rejection in experimental transplant models. The aim of this work was to develop an HPLC-MS method to measure FK778 in plasma for pharmacokinetic studies. The equipment used for mass evaluation was an HLPC coupled to an ion trap analyzer through an electrospray source. After precipitation of plasma proteins with acetonitrile, the supernatant was injected onto an analytical RP-C18 column. Chromatographic separation was performed under isocratic conditions, using a mobile phase consisting of ammonium acetate buffer and acetonitrile (55:45. vol/vol). MS detection was performed in the negative ionization mode by monitoring the molecular ion of FK778 (m/z 307) and IS (m/z 269), using selected ion monitoring for both. However, we observed peaks corresponding to dimers, trimers, and tetramers of FK778 (m/z 637, m/z 945, m/z 1274). The HPLC-MS method was applied to pharmacokinetics in animal models showing comparable results to those obtained by an HPLC-UV assay at 290 nm. Good agreement was observed in the plasma FK778 concentration versus time curves. The rapid preparation of samples and the short run-time make this method attractive for use in clinical practice.

Efficacy of Malononitrilamide FK778 in a Preclinical Model of Small Bowel Transplantation

In a swine model of orthotopic small bowel transplantation, we assessed the efficacy of combined immunosuppressive therapy with low-dose tacrolimus plus FK778, compared with high-dose tacrolimus monotherapy. The small bowel was replaced in 23 piglets: group 1 (n = 5), no immunosuppression; group 2 (n = 12), oral tacrolimus to maintain whole blood trough levels between 15 and 25 ng/mL; and group 3 (n = 6), oral FK778 4 mg/kg/d, plus oral tacrolimus to maintain whole blood trough levels between 5 and 15 ng/mL. Follow-up time was limited to 60 days. Overall survival rates at 30 and 60 days were 0% and 0% in group 1, 30% and 0% in group 2, and 66% and 66% in group 3, respectively. The median survival time was 11 days in group 1, 28 days in group 2, and more than 60 days in group 3. The differences between groups 3 and 1 and between groups 3 and 2 were statistically significant. The numbers of major bacterial infections were 19 in group 2 (1.9 episodes per animal) and 3 in group 3 (0.75 episodes per animal). The infectious-related mortality rate was 70% in group 2 (7 cases) and 0% in group 3 (P < .05). Acute cellular rejection was absent or mild in 85% of group 2 stomal biopsy specimens and in 100% of group 3 biopsy specimens. In conclusion, combination therapy of low-dose tacrolimus is potentiated by FK778 to prevent acute cellular rejection and prolong small bowel transplant survival in pigs.

New Strategies in Immunosuppression

New immunosuppressive strategies that can prevent both acute and chronic rejection are being investigated to achieve graft tolerance and to minimize side effects and toxicity that may lead to graft loss. Drug pharmacokinetics and pharmacodynamics, as well as pharmacogenetics, all play a role in customizing treatment to the individual patient. To improve patient compliance, new drug formulations are on trial, such as the modified- release oral form of tacrolimus MR4 for once daily administration, which seems to be equivalent to bid administration in terms of steady-state exposure. Monoclonal/polyclonal antibodies are increasingly used in the induction phase in protocols where steroids are discontinued early. However, discontinuing steroids carries a high risk of acute rejection or organ failure in some subgroups of patients. The supposed benefit of steroid discontinuation may not be enjoyed by all patients. Minimizing anticalcineurin agents may prove to be similarly or even more advantageous. The use of new drugs and new combinations has greatly improved short-term transplant outcomes. The new goal is, therefore, to improve long-term results and particularly to prevent chronic rejection, thus increasing patient and organ survival.

Uretero-neocystostomy in a swine model of kidney transplantation: a new technique

BACKGROUND

Swine constitute a well-characterized large animal model for kidney transplantation (K-Tx) although the uretero-neocystostomy represents a crucial aspect because of the very small caliber of the ureter and the mucosal susceptibility to the edema during surgical management. Besides infectious and occlusive complications limited the employment of a stent and the peculiar anatomy of the species prevents its removal without an operative approach. These features find an equivalent in children (<4 year old) candidates to urological surgery. We investigated an uretero-neocystostomy technique to be applied in case of narrow caliber without using endoluminal device.

MATERIALS AND METHODS

Thirty unrelated large-white piglets, divided into three equal groups (n = 10) on the basis of the uretero-neocystostomy technique used, underwent K-Tx while receiving a double immunosuppressive regimen. We developed a direct uretero-neocystostomy (Direct) technique and compare this with the gold standard Lich-Gregoir (LG) and Leadbetter-Politano (LP) techniques.

RESULTS

After 60 days, the ureteral complication rates were: group 1 (LG): 60% (6/10, three early and three late strictures); group 2 (LP): 40% (4/10, two leakages, one early stricture, and one isolated ureteral dilatation); group 3 (Direct): 10% (1/10, one isolated ureteral dilatation). No bacterial cystitis or nephritis occurred; retrograde cystograms were negative for refluxes in every group.

CONCLUSIONS

The comparison between the old techniques and the new one (LG and LP versus Direct) showed a lower incidence of complications among the animals that underwent the new direct technique (P < 0.05). This technique could be applied clinically in selected pediatric cases either of transplantation or reflux.

Platelet-Independent defect in hemostasis associated with sirolimus use

Sirolimus is currently used to prevent rejection of solid organ transplant, and sirolimus-eluting stents have shown promise for the prevention of coronary artery restenosis. Thrombocytopenia is a well-known adverse effect of sirolimus limiting its use. Herein we report on a patient in whom sirolimus caused a platelet-independent hemostasis defect. The patient was a 52-year-old woman who underwent renal transplant with consequent normal kidney function. The immunosuppressive regimen included basiliximab, steroids, and cyclosporine induction later shifted to sirolimus and mycophenolate due to biopsy findings of tubular necrosis on day 6 posttransplantation. At discharge the serum creatinine was 0.7 mg/dL. Four months after transplantation the patient was admitted to our hospital because of fever (37.5 degrees C to 38 degrees C), anorexia, and asthenia. Blood analysis showed: creatinine 1.7 mg/dL, Hb 9.6 g/dL, WBC 6 x 10(3)/microL, PLT 123 x 10(3)/microL, liver function tests normal, LDH 720 mU/mL, fibrinogen 628 mg/dL, d-dimer 0.42 ng/mL, FDP > 40 ng/mL, INR 1.10, PT 87%, aPTT 40 seconds. Cultures and tests for infection were negative. Serum sirolimus level was 25.9 ng/mL. The following day the serum creatinine rose to 2.3 mg/dL and diuresis fell to 20 mL/h. Multiple bleeding times (Ivy test) performed before the renal biopsy were repeatedly over 30 minutes (normal 3 to 5 minutes), despite normal platelet count and platelet function studies. There was no spontaneous aggregation and in vitro aggregation was normal (collagen, ADP, adrenalin, and ristocetin induced). Coagulation studies showed a defect in fibrin formation and a reduction of fibrinolysis. Suspension of sirolimus treatment was followed by remission of fever, improvement of renal function (serum creatinine 1.2 mg/dL), and normalization of bleeding time.

[Experimental kidney transplantation: a comparison between different models]

AIM

Two different models of kidney transplantation have been compared using 3 different techniques. The kidney grafts were procured from living donors (laparoscopic or laparotomic technique) and from cadaveric donors.

METHODS

Twenty-four outbred piglets (Large White, weight range 24-27 kg) underwent kidney transplantation. We divided the recipients into 2 groups with the following characteristics: group 1 (n=12) was represented by orthopic kidney recipients whose grafts were retrieved by laparoscopic or lapartomic technique from living unrelated donors; group 2 (n=12) was constituted by heterotopic kidney recipients whose grafts were retrieved by laparotomic technique from unrelated cadaveric donors. In both groups, Grogoire-Lich technique and Politano-Laedbetter technique were used in order to perform ureteral-vescical anastomosis together with a new technique developed from our experience called Politano-Laedbetter modified. All transplanted pigs underwent double immunosoppressive steroid therapy (tacrolimus and micofenolate mofetil). The pigs were observed for 60 days.

RESULTS

The survival rates in group 1 and in group 2 were 75% (n=9) and 66% (n=8), respectively. No significative differences were noted in length of operative time, creatinemia and ureamia levels in both study groups. The Gregoire-Lich technique was associated with a higher rate of complications.

CONCLUSION

Two different experimental models of kidney transplantation are feasible in pigs. The classic technique could be combined with the orthopic one based on the type of study needed.

The influence of surgery, immunosuppressive drugs, and rejection, on graft function after small bowel transplantation: a large-animal study

In this study we assessed functional changes (motility and absorption) of intestinal allografts in a large-animal model of orthotopic small bowel transplantation in swine. Studies were performed on non-rejecting animals in the early and late stages after transplantation and after induction of different grades of acute rejection. Immunosuppression consisted of oral FK506 and mycophenolate mofetil. In each study group we regulated drug administration, in terms of dosage and timing, in order to induce different grades of acute rejection or to prevent it. Migrating myoelectrical complexes were recorded in fasting animals so that motility could be assessed. Mucosal biopsy of the allograft and D-xylose absorption tests were performed on the same day as the motility study. In the early stages following intestinal transplantation, we observed in non-rejecting animals a slightly increased graft motility and a marked carbohydrate malabsorption. Recovery of the carbohydrate absorption capacity occurs within 2 months, but the persistence of diarrhea leads to partial malabsorption and to a lack of normal weight gain. Motility reduction correlates with the grade of acute rejection and becomes significant at a later stage, when rejection is severe. Allograft carbohydrate absorption, on the contrary, is markedly reduced in all rejecting pigs, irrespective of the grade of rejection. In summary, the early functional impairment of non-rejecting animals has multifactorial causes due to surgery and immunosuppression (drug toxicity), and its occurrence suggests the need for specific guidelines for clinical early postoperative enteral feeding. The functional studies adopted here are helpful in defining the grade of functional impairment with or without acute rejection; however, they are not useful for early detection of ongoing acute rejection of the small bowel graft.

Jejunum free flap in hypopharynx reconstruction: case series

BACKGROUND

Surgical treatment of hypopharyngeal cancers with extension to the retrocricoid region generally requires a circumferential pharyngolaryngectomy followed by a reconstruction of the removed segment of the upper digestive tract. Historically, many techniques have been used in order to achieve a safe and functional reconstruction. Jejunum interposition is generally considered the best reconstructive technique.

METHODS

This study examines the details of the surgical technique, the complications, the oncological and the functional results in a series of 29 consecutive patients submitted to circumferential pharyngoesophageal resection for advanced hypopharyngeal cancer followed by reconstruction with a free flap of jejunum.

RESULTS

Three of the transplants failed because of venous thrombosis. The overall success rate was 90%. There were no general complications. A good swallowing has been preserved in all our patients. All our patients where a phonatory prosthesis was positioned (20/29) were able to achieve speech following speech therapy and all were satisfied with their own capacity to communicate.

CONCLUSIONS

The prognosis of hypopharyngeal tumours (18-40% at 5 years) remains poor, but jejunum autografts are being shown to be an excellent choice for the reconstruction of the cervical hypopharyngo-oesophagus offering the patient fast rehabilitation and a reasonable quality of survival. Our experience confirm that this kind of reconstruction is safe with a good results in improving oncologic controls and restoring a good quality of life.

Irreversible intestinal failure, nutrition support, and small bowel transplantation

OBJECTIVES

Prolonged total parenteral nutrition (TPN) is a palliative but life-saving treatment for patients with irreversible intestinal failure (IIF). During the past few years, intestinal transplantation (ITx) has become the most realistic alternative to TPN.

METHODS

We identified potential candidates for ITx, reported clinical data of the international Intestinal Transplant Registry, and analyzed the intestinal function after transplantation and the common nutrition strategies usually adopted in the recipients.

RESULTS

At present, candidates for ITx are patients with IIF who develop a life-threatening complication during TPN treatment. During the past few years, clinical results have improved mainly in relation to the progress in immunosuppression, but prevention of the acute cellular rejection (ACR) is still the key point. ACR, high doses of immunosuppressant drugs, and intestinal bacterial translocation can exacerbate intestinal malabsorption and sustain systemic complications such as sepsis and multiorgan failure. Early enteral alimentation is started after ITx and gradually increased. To prevent dehydration and malnutrition caused by persistent diarrhea, parenteral nutrition is frequently maintained for 1 to 2 mo. More than 66% of long-term recipients become nutritionally independent of TPN.

CONCLUSIONS

ITx is now a life-saving option for patients with IIF and severe complications from TPN. Clinical and nutritional management of the recipients is a complex procedure and requires a great deal of expertise. After transplantation most adults maintain adequate nutrition status and children have normal growth. Multiple episodes of ACR, early and persistent dehydration, and malabsorption are still common problems that influence the recipient's quality of life.

Factors influencing Islet of Langerhans graft function and monitoring

Transplantation of islet of Langerhans represents a viable therapeutic option for insulin-dependent diabetes mellitus. Dramatic progress has been recently reported with the introduction of a glucocorticoid-free immunosuppressive regimen that improved success rate, namely, insulin independence for 1 year or more, from 8% to 100%. The fate of islet grafts is determined by many concurrent phenomena, some of which are common to organ grafts (i.e. rejection), while others are unique to nonvascularized cell transplants, including transplant cell mass and viability, as well as nonspecific inflammation at the site of implant. Moreover, islet grafts lack clinical markers of early rejection, making it difficult to recognize imminent rejection and to implement intervention with graft-saving immunosuppressive regimens. In the present review, we will address the problems influencing islet graft success and the monitoring of islet cell graft function.