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Biomedical subjects

J Pirenne

Publications and source records attributed to J Pirenne.

At least 37 records · Page 2Linked to original sources
PubMed2001

Type of donor aortic preservation solution and not cold ischemia time is a major determinant of biliary strictures after liver transplantation.

The development of biliary strictures (BSs) after liver transplantation (LT) continues to affect 10% to 30% of patients, causing substantial morbidity. The cause of BSs is multifactorial, including technical, immune, and, in particular, ischemic factors. The importance of adequate flushing of the peribiliary arterial tree has been stressed. We hypothesized that high-viscosity (HV) preservation solutions in the donor do not completely flush the small donor peribiliary plexus, leading to inadequate preservation of the bile ducts and posttransplant BSs. To test this hypothesis, we retrospectively compared the incidence of BSs in 2 groups of adults undergoing LT using different types of aortic preservation solution in the donor: group 1 (n = 24), low-viscosity (LV) Marshall solution; and group 2 (n = 27), HV University of Wisconsin (UW) solution. All donors in both groups received additional portal flushes with UW. All LTs were performed between November 1995 and August 1998 at 2 centers by the same surgeon, eliminating a technical bias. Terminal duct-to-duct anastomosis was performed in all recipients except 1 patient in group 1, who underwent a bile duct-to-jejunum anastomosis. BSs were first suspected on clinical and biochemical grounds and then confirmed by endoscopic retrograde cholangiopancreatography. Identical medical protocols were used in all patients. One-year patient survival rates in groups 1 and 2 were 92% and 100%, respectively (P =.9). One-year graft survival was identical to patient survival. The incidence of BSs in group 1 was 4.1% (1 of 24 patients), compared to 29.7% in group 2 (8 of 27 patients; P =.02). The BS in group 1 occurred 4 months post-LT and was anastomotic. BSs in group 2 occurred between 1 and 12 months post-LT and were anastomotic, extrahepatic, intrahepatic, or combined intrahepatic and extrahepatic. There were no significant differences in the following factors between groups 1 and 2: donor age, local versus imported liver, split-liver or full-liver transplantation, incidence of multiple vessels in the donor liver, indications for LT, recipient age, T-tube versus no T-tube, post-LT peak aspartate aminotransferase level, and treatment for rejection. There was no hepatic artery thrombosis or primary nonfunction in either group. Interestingly, cold ischemia time (CIT) was longer in group 1, which had the least incidence of BSs (692 +/- 190 v 535 +/- 129 minutes in group 2; P =.001). Follow-up was longer in group 1 (28.9 +/- 8.3 v 15.6 +/- 8 months in group 2; P =.0001). Preservation costs per procurement were 1.9 times greater in the UW group than in the Marshall group. Donor aortic flushing with an HV preservation solution leads to more frequent BSs compared with an LV preservation solution. The impact of preservation solution outweighs the previously described deleterious impact of prolonged CIT. Mixed preservation solution (Marshall solution in the aorta, UW solution in the portal vein) might protect against BS formation while providing optimal liver graft preservation, function, and survival despite a mean CIT longer than 10 hours.

Adenosine↗
PubMed2001

Pediatric renal transplantation: a single Belgian center experience over 20 years.

Between 1980 and 2000, 100 renal transplantations were performed in 91 children at the pediatric unit of the University Hospital Leuven. The proportion of living-related donors (LRD) was 20%. Patient survival rates were 94% at 3 yr, 91% at 5 yr, and 87% at 10 yr. The commonest causes of death were bacterial infections and cardiovascular complications, which underscores the need for aggressive preventative procedures in this area after transplantation. The overall actuarial graft survival was 82% at 3 yr (n = 73), 74% at 5 yr (n = 53), and 56% at 10 yr (n = 29). In the LRD group, the graft survival was 10% better than the overall actuarial graft survival rate. The overall incidence of acute rejection was 55% but has shown a decrease to 34% in more recent years (1993-99). The major causes of graft failure were chronic rejection and recurrence of the initial disease, and these remain a major concern. Improvement of these results could be achieved by tight immunosuppression management, early aggressive treatment of infection and rejection, and careful educational and psychological support.

Adolescent↗
PubMed2000

Portal vein thrombosis in adults undergoing liver transplantation: risk factors, screening, management, and outcome.

BACKGROUND: Portal vein thrombosis (PVT) has been seen as an obstacle to liver transplantation (LTx). Recent data suggest that favorable results may be achieved in this group of patients but only limited information from small size series is available. The present study was conducted in an effort to review the surgical options in patients with PVT and to assess the impact of PVT on LTx outcome. Risk factors for PVT and the value of screening tools are also analyzed. METHODS: Adult LTx performed from 1987 through 1996 were reviewed. PVT was retrospectively graded according to the operative findings: grade 1: <50% PVT +/- minimal obstruction of the superior mesenteric vein (SMV); grade 2: grade 1 but >50% PVT; grade 3: complete PV and proximal SMV thrombosis; grade 4: complete PV and entire SMV thrombosis. RESULTS: Of 779 LTx, 63 had operatively confirmed PVT (8.1%): 24 had grade 1, 23 grade 2, 6 grade 3, and 10 grade 4 PVT. Being male, treatment for portal hypertension, Child-Pugh class C, and alcoholic liver disease were associated with PVT. Sensitivity of ultrasound (US) in detecting PVT increased with PVT grade and was 100% in grades 3-4. In patients with US-diagnosed PVT, an angiogram was performed and ruled out a false positive US diagnosis in 13%. In contrast with US, angiograms differentiated grade 1 from grade 2, and grade 3 from grade 4 PVT. Grade 1 and 2 PVT were managed by low dissection and/or a thrombectomy; in grade 3 the distal SMV was directly used as an inflow vessel, usually through an interposition donor iliac vein; in grade 4 a splanchnic tributary was used or a thrombectomy was attempted. Transfusion requirements in PVT patients (10 U) were higher than in non-PVT patients (5 U) (P<0.01). In-hospital mortality for PVT patients was 30% versus 12.4% in controls (P<0.01). Patients with PVT had more postoperative complications, renal failure, primary nonfunction, and PV rethrombosis. The overall actuarial 5-year patient survival rate in PVT patients (65.6%) was lower than in controls (76.3%; P=0.04). Patients with grade 1 PVT, however, had a 5-year survival rate (86%) identical to that of controls, whereas patients with grades 2, 3, and 4 PVT had reduced survival rates. The 5-year patient survival rate improved from the 1st to the 2nd era in non-PVT patients (from 72% to 83%; P<0.01), in grade 1 PVT (from 53% to 100%; P<0.01), and in grades 2 to 4 PVT (from 38% to 62%; P=0.11). CONCLUSIONS: The value of US diagnosis in patients with PVT depends on the PVT grade, and false negative diagnoses occur only in incomplete forms of PVT (grades 1-2). The degree of PVT dictates the surgical strategy to be used, thrombectomy/low dissection in grade 1-2, mesoportal jump graft in grade 3, and a splanchnic tributary in grade 4. Taken altogether, PVT patients undergo more difficult surgery, have more postoperative complications, have higher in-hospital mortality rates, and have reduced 5-year survival rates. Analysis by PVT grade, however, reveals that grade 1 PVT patients do as well as controls; only grades 2 to 4 PVT patients have poorer outcomes. With increased experience, results of LTx in PVT patients have improved and, even in severe forms of PVT, a 5-year survival rate >60% can now be achieved.

Adult↗
PubMed2000

An improved model of acute liver failure based on transient ischemia of the liver.

HYPOTHESIS: A reproducible and potentially reversible model of acute liver failure in the pig is feasible based on transient ischemia of the liver. DESIGN: To determine the shortest period of liver ischemia sufficient to cause 100% mortality, ischemia of the liver was induced for different lengths of time, starting with 6 hours. If the pig survived, ischemia time was prolonged for 2 hours in the next animal. In the first group, the common bile duct was not tightened. In the second group, the common bile duct was tightened. SETTING: The Laboratory for Hepatopathophysiology, Catholic University, Leuven, Belgium. PARTICIPANTS: Female stress-negative Belgian Landrace pigs weighing 18 to 22 kg. INTERVENTIONS: During preparatory surgery, all ligaments around the liver and connective tissue around the liver hilum were transected and an end-to-side portacaval shunt was made. Vessel loops were placed around the branches of the hepatic artery and bile duct. Three days later, in fully awake pigs, the loops were tightened. MAIN OUTCOME MEASURES: Mortality. Development of acute liver failure was determined based on neurologic, biochemical, and pathological variables. RESULTS: When occluded for 10 hours, all pigs in group 2 (n = 5) [corrected] died between 12 and 17 hours after the induction of ischemia. All pigs developed typical acute liver failure. Tissue specimens showed 90% necrosis of the liver parenchyma. CONCLUSION: A highly reproducible and potentially reversible model of acute liver failure in the large animal has been established.

Animals↗
PubMed2000

[Liver transplantation with a graft taken from a heart transplant patient who was brain-dead].

The shortage of organ donors has led to progressive softening of selection criteria for organ donation. We report on hepatic transplantation in a 55-year-old woman with primary biliary cirrhosis, whose donor was a 50-year-old heart transplant recipient who became brain stem dead, due to cerebral bleeding 8 months after transplantation. An orthotopic liver transplantation was performed. The postoperative course was uneventful and the recipient was alive and had normal liver function after a 42-month follow-up. Analysis of the literature included ethical consideration, potential hepatotoxic effects of immunosuppressive drugs and modification of the graft immunogenicity. It confirms that transplanted patients should not be a priori excluded from organ donation.

Brain Death↗
PubMed1999

Poor outcome in patients with diabetes mellitus undergoing liver transplantation.

BACKGROUND: Relatively few studies have examined the influence of pretransplant diabetes on survival after an orthotopic liver transplant (OLT), and those published to date show only minor increases in infection rates among diabetics and no increase in mortality. METHODS: We examined the effect of diabetes mellitus on survival after OLT. 1005 adults underwent OLT between 1982 and May 1997. Seventy-eight patients with pretransplant diabetes mellitus (7.8% of all OLT, 38 insulin treated, 25 tablet treated, 15 diet controlled) were identified and compared with controls matched for age, sex, and date of first transplant and also with all nondiabetic adult liver recipients undergoing OLT during the same period. RESULTS: In patients undergoing OLT survival was worse in diabetics than in the comparison group (P=0.002) and vs. all adult nondiabetics undergoing (n=927) (P=0.004); in diabetics with alcoholic liver disease (ALD) vs. all nondiabetics with alcoholic liver disease (P= <0.0001); and in insulin-treated compared with non-insulin-treated diabetics (P=0.05). Multivariate analysis showed type of diabetes (P=0.001) and ALD (P=0.024) to be the most significant independent variables adversely affecting survival. Survival in diabetics undergoing OLT could be further stratified according to whether diabetics were insulin treated. CONCLUSIONS: Poorer outcome in the diabetics undergoing OLT, particularly in those with ALD, suggests the need for a more detailed pre-OLT assessment of these patients, particularly those with insulin and tablet controlled diabetes.

Adult↗
PubMed1999

Use of grafts procured from organ transplant recipients.

BACKGROUND: Massive intracerebral bleeding may cause brain stem death in transplant (Tx) recipients early or late postTx. We addressed the question as to whether Tx recipients may safely be used as organ donors. In particular, it is feared that exposure to immunosuppressive drugs may render those organs unsuitable for Tx. METHODS: We reviewed two case reports of liver grafts procured from Tx patients. In addition, we conducted a survey within United Kingdom Transplant Support Service Authority (UKTSSA) to delineate the UK experience in that area. RESULTS: Donor 1 was an 50-year-old heart Tx recipient who became brain stem dead due to cerebral bleeding 8 months postTx. His liver was used in an 55-year-old patient with PBC who is alive and well more than 22 months postTx. Donor 2 was a 22-year-old kidney Tx patient who developed cerebral bleeding 4 years postTx. His liver was used in a 65-year-old patient with PBC who is doing well more than 27 months postTx. During the study period of 1989-1995, 13 organs (9 kidneys, 3 hearts, 1 liver) were procured from 6 brain stem dead Tx patients (3 long, 2 heart, and 1 kidney Tx patients). Seven recipients are enjoying satisfactory graft function 1 to 7 years postTx; one kidney Tx recipient was relisted 4 years postTx due to chronic rejection; five functionning grafts were lost to patient death; primary nonfunction was seen in one heart Tx recipient. CONCLUSIONS: Tx patients can be successfully used as organ donors. In particular, chronic exposure to immunosuppression is not per se a contraindication to donation. Tx physicians confronted with the rare and tragic event of brain stem death in a Tx patient should not a priori exclude these patients from donation.

Adult↗
PubMed1999

Clostridium difficile colitis after kidney and kidney-pancreas transplantation.

OBJECTIVE: To determine the timing and risk factors involved in the development of Clostridium difficile (CD) colitis in kidney and kidney-pancreas transplant recipients. BACKGROUND DATA: The incidence of CD colitis after kidney and kidney-pancreas transplantation has not been studied in detail. The question of whether the immunosuppressed transplant recipient is more prone to CD colitis and its complications (i.e., megacolon, perforations) and the risk factors involved have not been determined. METHODS: We retrospectively reviewed our experience in kidney and kidney-pancreas recipients who received transplants between January 1, 1985 and December 31, 1994. We divided these recipients into three groups: pediatric kidney recipients, adult kidney recipients, and kidney-pancreas recipients. For each group, we assessed the timing of infection, primary disease, colitis treatment, and any concurrent complications or risk factors. RESULTS: Of 1932 transplants, 159 recipients developed post-transplant CD colitis. 132 charts were available for review. Forty-three pediatric kidney recipients developed CD colitis. Their mean age was 3.2 yr; 74% (n = 37) of them developed their colitis during their initial hospital stay, with the mean timing of infection being 33 d. Forty-one (95%) had undergone intra-abdominal placement of the graft, with renal artery anastomoses to the aorta. Fifty adult kidney recipients developed CD colitis. Thirteen (26%) developed colitis during their initial hospital stay, with the mean timing of infection (for all adult kidney recipients) being 15 months. Thirty-nine kidney-pancreas recipients developed CD colitis. Mean timing of infection was 6 months. The overall incidence of CD colitis was 8%, with 16% in the pediatric kidney group, 15.5% in the kidney-pancreas group, and 3.5% in the adult kidney group. The difference in mean timing of infection was significant between the three groups (p < 0.001 for pediatric versus adult kidney recipients, p = 0.002 for pediatric kidney versus kidney-pancreas recipients, and p = 0.2846 for adult kidney versus kidney-pancreas recipients). CONCLUSION: The incidence of CD colitis is increased in pediatric kidney and kidney-pancreas recipients. Young recipient age ( < 5 yr), female gender, treatment of rejection with monoclonal antibodies, antibiotic use, and intra-abdominal graft placement have been shown to increase the incidence of this disease. Further studies concerning prevention in the high-risk groups are needed.

Adolescent↗
PubMed1998

Inferior outcome of cadaveric kidneys preserved for more than 24 hr in histidine-tryptophan-ketoglutarate solution. Leuven Collaborative Group for Transplantation.

BACKGROUND: During recent years, an increasing number of transplant centers within the Eurotransplant organization have used histidine-tryptophan-ketoglutarate (HTK) solution instead of University of Wisconsin (UW) solution as their preferred cold storage solution for abdominal organ preservation. We report on our single-center experience on the outcome of imported kidneys preserved with either HTK or UW solution in relation to the duration of cold ischemia time (CIT). METHODS: Between July 1989 and July 1997, 323 cadaveric kidneys preserved with UW or HTK and imported as a result of an exchange within the Eurotransplant organization were transplanted at our institution. CIT was <24 hr in 216 kidneys (UW: n=174, HTK: n=42) and > or =24 hr in 107 kidneys (UW: n=67, HTK: n=40). Renal functional outcome was evaluated by comparing delayed graft function and initial non-function rates, daily urinary output, the evolution of serum creatinine, and creatinine clearance at 1, 3, 5, 7, and 14 days and at 1, 3, 6 and 12 months, and graft survival at 1 year after transplantation in relation to the type of cold storage solution and CIT < or > or =24 hr. RESULTS: Whereas the incidence of delayed graft function did not differ significantly between kidneys preserved for less than 24 hr in UW (18.6%) or HTK (26.2%), this rate increased to 50% in HTK kidneys compared to 23.9% in UW kidneys when CIT exceeded 24 hr (P=0.006). Mean serum creatinine and creatinine clearance values were better at 1 and 5 days postoperatively in kidneys preserved <24 hr with UW as compared to HTK (P<0.05). After 24 hr of CIT, HTK-preserved kidneys showed an impaired renal function, not only in the immediate postoperative phase but also at 1, 3, 6, and 12 months after transplantation (P<0.05). Graft survival at 1 year was 92.9% in UW vs. 87.5% in HTK kidneys preserved for <24 hr (NS), and 91% vs. 77.4% when CIT exceeded 24 hr (P=0.059). CONCLUSIONS: From these single-center findings, it can be concluded that UW is superior to HTK in kidney preservation, particularly when CIT exceeds 24 hr.

Adenosine↗
PubMed1998

Effect of peritransplant FTY720 alone or in combination with post-transplant tacrolimus in a rat model of cardiac allotransplantation.

FTY720 is a recently discovered compound that is derived from the fungus Isaria sinclairii. Using a DA donor-to-LEW recipient rat combination, we assessed the efficacy of peritransplant FTY720 alone or in combination with post-transplant tacrolimus on the survival of cardiac allografts. Peritransplant FTY720 given orally at a dose of 5 mg/kg on days-1 and 0 prolonged graft survival from 5 to 13 days (P < 0.05). Combining peritransplant FTY720 with post-transplant tacrolimus resulted in a further prolongation of allograft survival. The lymphocyte count in transplanted rats decreased within 24 h to 46.6%. Analysis of lymphocyte subsets by FACS revealed that FTY720 affected the total population of CD3-bearing T cells while the ratio of CD4 to CD8 cells remained unchanged. Kidney and liver biochemistry remained elevated for 2 weeks. In conclusion, FTY720 is a powerful immunosuppressive agent when used as induction therapy and may have an additive effect--perhaps a synergistic one--with post-transplant tacrolimus.

Animals↗
PubMed1998

Encouraging results of split-liver transplantation.

BACKGROUND: Liver donor shortage presently accounts for a 10 per cent waiting list mortality rate. Split-liver transplantation (SLT) can improve utilization of this scarce resource. METHODS: Twenty-four SLTs (11 left, 13 right grafts) from 13 livers were performed in 23 patients (nine adults, 14 children), comprising 4.5 per cent of all orthotopic liver transplants (14 urgent or emergency, ten elective). The left graft comprised segments II and III, whereas the right graft comprised segments V-VIII in eight cases, IV-VIII in three, and segments I, IV-VIII, and I, V-VIII in one case each. Additional arterial extension grafts were required in six of 24 cases, and portal venous interposition graft in one. RESULTS: Twenty-one grafts showed good initial function, with one primary non-function and two initial poor function. The median peak aspartate aminotransferase level was 782 (range 94-2301) and 982 (range 382-2520) units/l for left and right grafts respectively. Five patients died (all urgent recipients), all within the first 30 days after surgery. Two SLT recipients underwent subsequent retransplantation. All ten elective recipients are alive. The 1-year actuarial patient and graft survival rates at a median follow-up of 20 months were 78 and 68 per cent respectively. CONCLUSION: These encouraging results compare favourably with those of reduced-size and whole-liver transplantation and justify wider application of this technique, thereby optimizing donor resource use.

Adult↗