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Biomedical subjects

H Bismuth

Publications and source records attributed to H Bismuth.

At least 217 records · Page 12Linked to original sources

Incidence of adverse reactions to cyclosporine after liver transplantation is predicted by the first blood level.

Despite the availability of whole-blood cyclosporine assays, the different responses of individual patients to its administration after transplantation continue to pose clinical problems, particularly with respect to toxicity. Fifty-seven recipients of first orthotopic liver transplants were studied between January 1992 and July 1992. Initial immunosuppression was carried out with azathioprine, methylprednisolone and cyclosporine, at a dose of 1 mg/kg/day adjusted to achieve blood levels between 400 and 600 ng/ml. Cyclosporine levels were measured 12 hr after the start of intravenous administration and correlated with the occurrence of toxic complications. Twelve patients experienced toxic complications in the first 7 days after orthotopic liver transplantation. These were neurological in six patients (of whom four also had kidney failure) and renal complications in the other six patients. All complications were reversed by reducing or stopping administration of cyclosporine. We noted excellent correlation between the occurrence of complications and cyclosporine whole-blood levels (p < 0.0001) despite the fact that levels did not exceed the therapeutic range. However, no correlation was observed between toxicity and cumulative dosage. In this study we were able to demonstrate that a standardized dose of cyclosporine does not prevent the occurrence of toxic side effects even when cyclosporine whole-blood levels are subsequently maintained in the therapeutic range. This highlights the importance of the first dose of cyclosporine and consequent early postoperative blood levels and indicates that these problems are unlikely to be overcome until a method of predicting individual requirements can be established in clinical practice.

Adolescent↗

Xenotransplantation: baboons as potential liver donors? Scientific and ethical issues.

The dramatic development of liver transplantation compared to a relative shortage of donors has brought a renewed interest to xenotransplantation. Because of anatomical and immunological compatibilities, nonhuman primates are the most appropriate donors. The aim of this work was to analyze the different problems of a baboon-to-man liver xenotransplantation. Thirty baboons bred in a French Primatology Center were studied. The analysis of anatomical, microbiological, and immunological data showed that only 8 baboons out of 30 were suitable as donors for xenotransplantation. Considering these data and the ethical issues, the actual feasibility of xenotransplantation programs is discussed.

Animals↗

Recent developments in liver transplantation.

The many developments that have occurred and continue to occur have also meant that the quality of life experienced by recipients of a successful graft is excellent, with more than 85% of patients returning to normal life and work (even having children). While long-term survival still occurs more frequently in favorable groups such as children with metabolic abnormalities or biliary atresia, results are still extremely good for adults, with 3-year survival figures after transplantation for cirrhosis in the order of 75%. These figures also continue to improve, and with the skill and enthusiasm that workers in this field display they seem destined to continue unabated.

Adenosine↗

Effect of extended cold ischaemia with UW solution on graft function after liver transplantation.

Studies in animals on the use of UW solution in liver transplantation have shown an inverse relation between cold ischaemia time (CIT) and graft function. There are few clinical data on this relation in human beings. We have investigated the effect of extended cold ischaemia in a prospective study. We assessed early graft function and subsequent outcome for 306 consecutive elective liver transplantations; for analyses, grafts were grouped according to CIT (< 12 h group A, > or = 12 h group B), since a preliminary study identified 12 h as a significant cut-off point. Initial graft function was better in group A than group B, as shown by maximum alanine aminotransferase activity (mean 623 [805] vs 946 [1148], p = 0.02), bile production on days 1-3 (p < 0.05), maximum serum bilirubin by day 10 (206 [166] vs 244 [163] mumol/l, p = 0.04), and frequencies of primary non-function (1 [0.4%] vs 4 [7%], p = 0.006) and hepatocyte necrosis on routine biopsy sample after reperfusion (18% vs 31%, p = 0.04). Long-term outcome was also better in group A than group B; graft and patient survival rates were higher and fewer retransplantations were needed. These findings suggest that cold ischaemia in UW solution for longer than 12 h is a risk factor for graft function and patient survival. We recommend that the limit of the safe CIT be reconsidered.

Adenosine↗

Lipid and apolipoprotein changes after orthotopic liver transplantation for end-stage liver diseases.

Orthotopic liver transplantation was performed in 37 patients with different endstage liver diseases. Changes in lipid and apolipoprotein concentrations were followed daily from day 1 to 20 after surgery and regularly thereafter until 12 months. When the acute effects of surgery had cleared away, there was a sharp drop in HDL-C, apo A-I and A-II from day 1 to 5, a stabilization at their lowest values from day 5 to 15 and then a progressive rise. Contrasting with this drop, triglycerides, apo B, C-II and C-III increased from day 1 to 5 with variable concentrations thereafter. Apo SAA considerably increased early after surgery and remained significantly higher than normal in most patients after 12 months. All other parameters returned to normal from 3 to 6 months after transplant. The mechanism leading to these lipid and apolipoprotein changes are discussed with respect to the distant effect of infusions, re-alimentation, immunosuppressive therapy and lipoprotein metabolism. The apolipoprotein concentrations appear very useful indicators of functional liver recovery.

Adult↗

Experimental study of the protective effect of intermittent hepatic pedicle clamping in the rat.

The tolerance of the liver to ischaemia during intermittent clamping of the hepatic pedicle was compared with that during a continuous Pringle manoeuvre. Three groups of rats undergoing total durations of clamping of 60, 90 and 120 min were studied. A temporary peroperative portacaval shunt was used to exclude the effects of splanchnic venous stasis and allow independent study of the effects of hepatic ischaemia. In each group, three methods of portal clamping were evaluated: a continuous Pringle manoeuvre (n = 10), a 30-min intermittent clamping (n = 10) and a 15-min intermittent clamping (n = 10). The clamp release time between the periods of liver ischaemia was 5 min. Survival at day 7 and postoperative changes in liver function (transaminase enzymes, bilirubin, bromsulphthalein elimination, liver adenosine 5'-triphosphate levels) were recorded. Intermittent clamping of the pedicle was tolerated significantly better than continuous clamping. This method optimizes the ability of the liver to tolerate extended periods of ischaemia. For a given duration of ischaemia, no additional improvement could be produced by shortening the intermittent clamping period from 30 to 15 min. These data suggest that, when the Pringle manoeuvre is used, it should be applied intermittently rather than continuously.

Animals↗

Prolongation of heart allograft survival in rats by interferon-specific antibodies and low dose cyclosporin A.

Interferons (IFNs) are important cytokines which exhibit antiviral, antitumor, anticellular, as well as immunoregulatory activities. Among these multiple activities, IFNs are potent inducers of MHC antigen expression of a great variety of cells, helper and maturation factors in B-cell antibody production, and macrophage function. IFNs may therefore play a critical role in triggering antigen recognition and allograft rejection. Cyclosporin A (CyA) is a potent immunosuppressor which selectively inhibits helper T-lymphocyte proliferation in response to alloantigen presentation. CyA has been reported to inhibit interleukin 2 and IFNgamma production by helper T lymphocytes. In addition, CyA may induce monocyte production of prostaglandin E2, which then reduces MHC class II expression on endothelial cells, monocytes, and macrophages. However, the clinical use of CyA is plagued by its toxic (in particular nephrotoxic) side-effects. These toxic effects are clearly dose-related. It may be very important to develop new products which can act synergistically with CyA to inhibit lymphokine production. The aim of this study was to investigate the effects of combined IFN-specific antibodies and low dose CyA on cardiac allografts in inbred strains of rats.

Animals↗

Non specific increased expression of class I major histocompatibility complex (MHC) antigens on rat liver grafts.

Major histocompatibility complex (MHC) antigens play a major role in the rejection reaction and their increased expression may increase the host response to the foreign graft. Several clinical and experimental studies have demonstrated increased expression of MHC antigens on the different cell components of liver allografts during rejection. However modified expression of MHC antigens may also occur in certain liver diseases, after cholestasis or on a regenerating liver. In this experimental study in inbred rats, we compared the expression of MHC antigens on liver cells during rejection and non-immunological situations (cholestasis, cytolysis, regeneration).

Animals↗

Primary treatment of hepatocellular carcinoma by arterial chemoembolization.

Two hundred and ninety-one patients with hepatocellular carcinoma were treated by chemoembolization (CE), using ethiodized oil, doxorubicin, and a gelatin sponge. Patients with thrombosis of either the portal vein or a main branch were excluded. The mortality rate in the first 2 months after treatment was 7% in noncirrhotic patients, 2.8% in patients with class A cirrhosis, 8% in patients with class B cirrhosis, and 37% in patients with class C cirrhosis. The tumor diameter remained the same in 55.3% of patients, was reduced by up to 50% in 20% of the patients, was reduced by more than 50% in 7.3% of the patients, and almost completely disappeared in 1.8% of the patients. The diameter of the tumor increased in 15.6% of patients. Forty-three patients underwent a resection or transplantation after chemoembolization. Histologic examination of the specimens revealed significant necrosis of the tumor. The long-term survival rate at 2 years was 49% for class A cirrhotics, 29% for class B cirrhotics, and 9% for class C cirrhotics. Complications included cholecystitis (10%), vasculitis (14%), renal decompensation (13%), an increase in ascites (14%), and jaundice (12%). Chemoembolization is an effective and safe initial treatment for hepatocellular carcinoma. It is effective in producing tumor necrosis and reducing the size of the tumor. Improvement in survival was noted when patients who underwent chemoembolization were compared with an historical series of untreated patients, and resection and transplantation are kept as options.

Adolescent↗

Fipexide-induced fulminant hepatitis. Report of three cases with emergency liver transplantation.

Fipexide belongs to a new class of cognition activators and is noted for its lack of amphetamin-like side effects. We describe three patients who developed fulminant hepatic failure less than 2 months after beginning fipexide administration. The mean interval from the onset of jaundice to the onset of encephalopathy was 8 days. Emergency liver transplantation was undertaken when factor V was 20% of normal or less and coma developed. All patients were transplanted less than 1 week after the onset of encephalopathy. Two survived and one died immediately after transplantation. Histologic examination of the livers revealed massive liver cell necrosis, predominantly centrilobular, and a moderate inflammatory infiltrate within the portal spaces. We conclude that fipexide can induce massive liver cell necrosis and fulminant liver failure. As a result of this life-threatening complication, reconsideration of the indications for this drug is warranted.

Adolescent↗

Management strategies in resection for hilar cholangiocarcinoma.

Between 1960 and 1990, resection was performed in 23 of 122 patients who underwent surgical treatment for hilar cholangiocarcinoma. Local excision of the lesion alone was performed in 10 cases (43%). Hepatic resection for tumor extending to the secondary bile ducts or hepatic parenchyma was performed in 13 cases (57%): extended right hepatectomy (3), right hepatectomy (1), extended left hepatectomy (6), left hepatectomy (2), and left lobectectomy (1). In three other cases, resection by total hepatectomy and liver transplantation was performed, but these were not included in the analysis of results for resection. Significant operative complications occurred in only two cases (8.7%), and the operative mortality rate was zero. In four cases, complete excision of the tumor could not be achieved macroscopically (macroscopic curative resection rate 19/122; 15.6%). In nine cases, the margins of the resected specimens were free from tumor on histologic examination (microscopic curative resection rate, 9/122; 7.4%). In 10 cases, the resection margins were found to contain tumor on histologic examination. The overall survival rate was 87% at 1 year, 63% at 2 years, and 25% at 3 years (median survival, 24 months). The survival and freedom from recurrence rates for patients with free resection margins was superior to that for patients with involved resection margins or residual macroscopic disease. A potentially curative resection, with histologically negative margins and no recurrence to date, was achieved in seven patients using the following procedures: local excision for two type I lesions; left hepatectomy plus excision of segment 1 for two type IIIb lesions and one type IV lesion; right hepatectomy and right hepatectomy plus excision of segment 1 for two type IIIa lesions. These results indicate that improved survival in hilar cholangiocarcinoma can be achieved by resection, with minimal morbidity and zero mortality rates, if histologically free resection margins are obtained. To achieve this, we recommend the following procedures for each type of lesion, based on our experience and on anatomic considerations: local excision for type I; local excision plus resection of segment 1 for type II; local excision, resection of segment 1, and right or left hepatectomy for types IIIa and b; hepatectomy plus liver transplantation for type IV.

Adenoma, Bile Duct↗

Reinfection of liver graft by hepatitis C virus after liver transplantation.

We have investigated hepatitis C virus (HCV) viremia before and after orthotopic liver transplantation (OLT). 38 patients were examined; 16 were anti-HCV positive and 22 anti-HCV negative pre-OLT in a RIBA-2 test (Ortho Diagnostic Systems Inc., Westwood, MA). HCV-RNA was detected using a modified nested polymerase chain reaction in 14/38 and 10/38 patients before and after OLT, respectively. 7 of these 14 subjects who were HCV-RNA positive before OLT were also positive for serum hepatitis B surface antigen. After OLT, six patients became HCV-RNA positive, likely as a result of transfusions, while four developed a probable recurrence of HCV infection. Infection of the liver graft by the same strain of HCV was indeed demonstrated by sequence analysis of a hypervariable domain (in the envelope region) in two cases. This establishes the possibility of HCV recurrence and shows the usefulness of polymerase chain reaction as the only assay currently capable of identifying HCV infection after OLT.

Base Sequence↗