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Purpose: The goal of our study was to determine whether dual-phase spiral CT angiography with 3D volume rendering could be used for preoperative evaluation and patient selection for orthotopic liver transplantation candidates. Method: Fifty consecutive potential candidates for liver transplantation were evaluated with dual-phase spiral CT with 3D volume rendering. Intravenous contrast medium was administered as bolus peripheral injection at 3 ml/s. The protocol consisted of a contrast-enhanced dual-phase spiral CT (arterial phase acquisition at 30 s after initiation of contrast medium injection followed by portal venous phase beginning at 60 s) with scan parameters of 0.75 s gantry rotation speed, 3 mm collimation, 5 to 6 mm/s table speed, and reconstruction at 1 mm intervals for arterial-phase images and 3 mm collimation for portal venous-phase studies (Siemens Plus 4 scanner; Siemens Medical Systems, Iselin, NJ, U.S.A.). All scan information was sent to a free-standing workstation (Silicon Graphics Onyx or Infinite Reality, Mountain View, CA, U.S.A.) for interactive real-time 3D volume rendering using a customized version of the Volren volume renderer (Silicon Graphics; Advanced Imaging Laboratory, Johns Hopkins Medical Institutions, Baltimore, MD, U.S.A.). The arterial phase was used to create vascular maps of the celiac axis including the origin(s) of the hepatic artery and origin of the superior mesenteric artery. The portal phase was used to define portal venous patency as well as the hepatic venous anatomy. All images were analyzed for vascular patency, shunting, or collateralization as well as the status of the underlying liver (i.e., liver size, cirrhosis, tumor, etc.). Results: All 50 studies were successfully completed without complication. The 3D CT angiograms defined key arterial and venous structures including origin(s) of the hepatic artery, portal vein and/or superior mesenteric vein thrombosis, cavernous transformation of the portal vein, and/or other collateral vasculature. Ten patients (20%) demonstrated anomalous anatomy at the origin(s) of the hepatic artery.Portal vein thrombosis with cavernous transformation of the portal vein was shown in six patients, and there were three cases of partial venous thrombosis. Underlying liver tumors as well as parenchymal liver disease were well defined. Hepatic masses were found in five patients. Masses were pathologically proven as hepatocellular carcinoma (n = 1), giant cavernous hemangioma (n = 1), hepatic adenoma (n = 1), and focal nodular hyperplasia (n = 2). Conclusion: Preliminary results suggest that dual-phase spiral CT with CT angiography can provide a comprehensive preoperative liver transplant evaluation, supplying the necessary information for patient selection and surgical planning. As a single, minimally invasive examination, this should significantly impact patient care by minimizing procedures and avoiding potential complications.

Phagocytosis and killing of circulating organisms by Kupffer cells (KCs) are discrete, important components of host defense. However, the killing mechanism(s) are not fully understood, and the potential role of adjacent nonparenchymal cells such as hepatic endothelial cells has not been defined. Rat KCs ∓ an hepatic endothelial cell enriched cellular fraction (HECEF) were incubated with Candida parapsilosis and assayed for phagocytosis and phagocytic killing by validated fluorochromatic vital staining. The role of reactive oxygen metabolites in KC phagocytic functions was examined by inhibition with superoxide dismutase and/or catalase. Diphenyleneiodonium and allopurinol were used to examine the potential roles of NADPH oxidase and xanthine oxidase, respectively, in generating these toxic oxidants. Coculture with HECEF increased KC phagocytic activity (from 75% to 88%) and candidacidal activity (from 20% to 31%). Superoxide dismutase, catalase, diphenyleneiodonium, or allopurinol caused inhibition of candidacidal activity, but did not affect phagocytosis, and did not block the potentiation of phagocytosis or of killing caused by coculture with HECEF. Reactive oxygen intermediates generated by both NADPH oxidase and xanthine oxidase-dependent pathways are important in KC killing of Candida parapsilosis. In vitro, KC phagocytosis and killing are potentiated (via a non-oxidant-mediated mechanism) by coculture with a preparation of hepatic non-parenchymal cells composed primarily of endothelial cells.

Background. A study was performed by 17 different U.S. liver transplantation centers to determine the safety and efficacy of conversion from cyclosporine to tacrolimus for chronic allograft rejection. Methods. Ninety-one patients were converted to tacrolimus a mean of 319 days after liver transplantation. The indication for conversion was ongoing chronic rejection confirmed by biochemical and histologic criteria. Patients were followed for a mean of 251 days until the end of the study. Results. Sixty-four patients (70.3%) were alive with their initial hepatic allograft at the conclusion of the study period and were defined as the responder group. Twenty-seven patients (29.7%) failed to respond to treatment, and 20 of them required a second liver graft. The actuarial graft survival for the total patient group was 69.9% and 48.5% at 1 and 2 years, respectively. The actuarial patient survival at 1 and 2 years was 84.4% and 81.2%, respectively. Two significant positive prognostic factors were identified. Patients with a total bilirubin of ≤10 mg/dl at the time of conversion had a significantly better graft and patient survival than patients converted with a total bilirubin >10 mg/dl (P=0.00002 and P=0.00125, respectively). The time between liver transplantation and conversion also affected graft and patient survival. Patients converted to tacrolimus ≤90 days after transplantation had a 1-year actuarial graft and patient survival of 51.9% and 65.9%, respectively, compared with 73.2% and 87.7% for those converted >90 days after transplantation. The mean total bilirubin level for the responder group was 7.1 mg/dl at the time of conversion and decreased significantly to a mean of 3.4 mg/dl at the end of the study (P=0.0018). Thirteen patients (14.3%) died during the study. Sepsis was the major contributing cause of death in most of these patients. Conclusions. Our results suggest that conversion to tacrolimus for chronic rejection after orthotopic liver transplantation represents an effective therapeutic option. Conversion to tacrolimus before development of elevated total bilirubin levels showed a significant impact on long-term outcome.

Purpose The role IL-6 plays in transplant rejection has been increasingly recognized, therefore, targeting the IL-6/IL-6R pathway may have applications in treatment of allograft rejection. This study evaluated the efficacy of a mousenized rat-anti-mouse IL-6R mAb, mMR16-1, in suppressing alloantibody responses. Methods and Materials C57BL/6 mice were sensitized with skin allografts from a HLA.A2 transgenic mouse, and treated with intraperitoneal injections of mMR16-1 or control antibody. Donor specific antibody (DSA) responses were monitored weekly for 5 weeks by measurement of serum anti-HLA.A2 antibodies in a flow cytometric antibody binding assay. Results mMR16-1 significantly reduced DSA responses to skin allograft, resulting in significant decreases of anti-HLA.A2 IgM (treated vs. control: 12.7+2.3 MFI vs. 22.9+3.2 MFI at day 14, p=0.00022), IgG2a (99.41 +35.31 MFI vs. 300.6+53.04 MFI at day 28, p=6.621E-05) and IgG1 (25.6+9.8 MFI vs. 40.01+7.7 MFI at day 28, p=0.029), respectively. Anti-IL6R treatments also normalized serum amyloid A (SAA), an acute phase reactant induced by IL-6 (p Conclusions The data indicate that antibody therapy targeting the IL-6/IL-6R pathway may serve as a strategy to suppress DSA generation. Future mechanistic studies to dissect various cellular compartments targeted by anti-IL-6R in the alloimmunity will shed more light on our understanding of the therapeutic properties of anti-IL-6R on rejection suppression.

OBJECTIVE: The authors report on experience with liver transplantation for infants younger than 1 year of age. SUMMARY BACKGROUND DATA: Over the last 15 years, orthotopic liver transplant has become the only lifesaving procedure available for infants with end-stage liver disease. Many transplant centers initially required infants to reach a specific weight or age to minimize morbidity and mortality. Size-appropriate infant donors also were uncommon. As a result, many children, in the first few years of life, died of their disease. The availability of reduced-size cadaveric and living-related liver transplants has offered the ability to transplant the young infant with liver failure. METHODS: The authors instituted a program to aggressively transplant infants with liver failure in the first year of life using both cadaveric and living-related liver donors. RESULTS: Between June 1991 and January 1995, 13 infants were transplanted for rapidly progressive liver failure. Infant age ranged from 4 to 11 months (mean, 7.5 months). The cause of liver failure included biliary atresia (11), alpha 1-antitrypsin deficiency (1), and liver failure secondary to echovirus 7 (1). The United Network for Organ Sharing status at the time of transplant ranged from status 4, intensive care unit bound (4 patients); status 3, hospitalized (4 patients); or status 2, failing at home (5 patients). Six patients (46%) received cadaveric whole organ (2) or segmental transplants (4). Seven patients (54%) received left lateral segment living-related transplants from parental donors. After operation, patients received cyclosporine or FK506-based immunosuppression. Three patients (23%) required four retransplants (two cadaveric for primary nonfunction; one living-related for graft thrombosis in the face of fungal infection and bile leak). Postoperative complications included primary nonfunction (15%), rejection (85%), graft vascular thrombosis (15%, two of three revascularized successfully), bacterial and fungal infections (77%), and viral infections (46%). Epstein-Barr virus-associated lymphoproliferative developed in two patients (15%). Intestinal perforation requiring reoperation developed in two patients (15%). Bile leaks requiring reoperation or transhepatic stinting or both developed in three patients (23%). Two patients died in the perioperative period (< 1 month) from a combination of primary nonfunction or graft thrombosis and sepsis. Overall survival was 85%, ranging from 11.0 months to 4.5 years. CONCLUSIONS: Orthotopic liver transplantation in infants younger than 1 year of age poses significant challenges from technical and infectious complications. Despite these barriers, overall patient survival is comparable to that of older children and adults.

We evaluated the effects of hemorrhagic shock/resuscitation (S/R) on hepatic reticuloendothelial system function, using an in vivo assay that discriminantly quantitates its two essential components, phagocytic clearance and phagocytic killing of double-labeled Escherichia coli injected intravenously. Rats were subjected to hemorrhagic shock at mean arterial pressure at 50 +/- 5 torr for 2 h, resuscitated, and survived. Hepatic phagocytic clearance was significantly decreased immediately following and 6 h after S/R, compared with sham-shocked rats, but recovered to normal levels after 24 h. Although hepatic killing efficiency was increased initially, and transiently depressed 6 h later, it was strikingly upregulated after 24 h. As a consequence, net hepatic killing was transiently suppressed at 0 and 6 h, but upregulated after 24 h. Pre-treatment with proinflammatory agonists, including endotoxin, IFN-gamma, or IFN-gamma + TNF-alpha enhanced both hepatic killing efficiency and net hepatic killing. These observations suggest that although hepatic killing function is initially impaired after the onset of S/R, it is strikingly upregulated 24 h later, simulating both the initial immunosuppression, and the later hyperinflammatory response to systemic S/R that could lead to multiple organ dysfunction syndrome.

This study was designed to quantitatively discriminate the specific xanthine oxidase (XO) inhibitory from the relatively nonspecific antioxidant activities of allopurinol, both in vitro and in vivo in the rat. XO activity, determined by the spectrophotometric assay for urate generation over time, was completely inhibited in vitro by allopurinol at concentrationsor = 200 microM. Allopurinol's antioxidant activity was determined in vitro using a linolenic acid peroxidation (LAP) assay. Although the known antioxidant butylated hydroxytoluene effectively inhibited LAP (80% inhibition of malondialdehyde generation at 10(1) microM), allopurinol (10(1)-10(3) microM) did not inhibit this LAP (p.01). Rat serum obtained after oral administration of allopurinol (100 mg/kg x 2 doses) did not suppress LAP in vitro more than did control rat serum. Following oral administration of allopurinol (2-50 mg/kg x 2 doses), dose-dependent inhibition of XO activity was observed in the homogenates of the liver (to 5% of control level; p.001) and the intestine (to 12% of control level; p.001). We conclude that while 2-50 mg/kg of oral allopurinol effectively suppresses XO activity in the rat liver and intestine, antioxidant activity is not seen even in doses up to 100 mg/kg. The selective enzymatic inhibitory effect of allopurinol at these doses therefore should provide a useful tool to allow the discrimination of the effects of xanthine oxidase in particular from the effects of reactive oxygen metabolites in general.

The liver is the major source of complement (C) components, but extrahepatic sources of C, such as macrophages and endothelial cells, have been hypothesized to contribute to inflammation. Our experiments demonstrate that extrahepatically produced C6 can contribute to hyperacute rejection. PVG (RT1c) rats with normal C activity (PVG (C+)) reject guinea pig cardiac xenografts in 0.5 +/- 0.2 hr, but fully C6-deficient PVG (RT1c) rats (PVG (C-)) reject guinea pig cardiac xenografts in 45 +/- 9 hr. PVG (C+) rats, which received liver transplants from PVG (C-) rats and retained all extrahepatic sources of C6, rejected guinea pig cardiac xenografts in 0.6 +/- 0.03 hr (n = 3). PVG (C-) rats, which received bone marrow transplants from PVG (C+) rats, had C6 levels restored to 10% of that of the donor and rejected guinea pig cardiac xenografts in 9 +/- 3.2 hr (n = 5). Thus, extrahepatic sources of C6 can contribute to xenograft rejection.

A major component of the organ injury mediated by toxic oxidants, such as seen following reperfusion of the ischemic liver, is due to the peroxidation of polyunsaturated fatty acids, especially of cell membranes. We utilized the measurement of exhaled breath ethane, a metabolic product unique to oxidant-mediated lipid peroxidation, as a noninvasive indicator of this process in swine liver subjected to warm ischemia/reperfusion. Under rigorously controlled anesthesia conditions, pig livers were subjected to 2 h of warm total ischemia, followed by reperfusion in situ. Expired air was collected and its ethane content quantitated by a novel gas chromatographic technique. The time course of breath ethane generation correlated closely with the appearance of hepatocellular injury as measured by impairment of Factor VII generation and other measures of liver integrity. Moreover, the administration of the specific superoxide free radical scavenger, superoxide dismutase (SOD), significantly attenuated both the elaboration of ethane and the hepatocellular injury. These findings not only provide confirmation of the previously reported link between hepatocellular injury by free radicals generated at reperfusion, but also establish the use of expired breath ethane analysis as a sensitive, specific, and noninvasive indicator of the injury process in real time.

Budd-Chiari syndrome is a rare, often fatal illness resulting from hepatic venous outflow obstruction. Surgically created portosystemic shunts are frequently necessary in these patients for portal decompression. Over the past 15 years, 30 patients have been surgically treated for this condition at the Johns Hopkins Hospital. Of the 22 long-term survivors (range, 6 months to 13 years), five (23%) have required further surgical intervention and five (23%) have required percutaneous intervention for shunt complications. Percutaneous procedures included angioplasty ( n = 10), atherectomy ( n = 1), and urokinase therapy ( n = 1). Of the five patients treated percutane-ously, one has died of complications from her disease. The remaining four have been followed up for a mean of 16.2 months (range, 5–31 months) and all are in stable condition. None of the five treated with percutaneous interventional procedures have required additional surgical procedures or shunt revisions. Although this series is small, the findings indicate that percutaneous intervention may play a strong adjunctive role to surgery in the treatment of selected patients with portosystemic shunt complications.

Despite improving success with liver t ransplanta t ion, the procedure remains contra indicated in pat ients with cirrhosis in whom severe hypoxemia develops as a result of intrapu lmonary shunting. 1 Several factors cont r ibute to the reluctance to perform t ransplants in these patients, including previous unsuccessful a t tempts at t ransplanta t ion , questions regarding the pathophysiologic cause of the condition, the sensitivity of the graf ted organ to hypoxemia, and the lack of documenta t ion of the reversibili ty of the shunt af ter t ransplantat ion.I , 2 Stoller et al.3 described an adul t pat ient with pr imary bil iary cirrhosis and modera te hypoxemia resul t ing from in t raputmonary shunt ing , who underwent successful liver t ransp lan ta t ion and had subsequent reversal of her shunting. In this case report we detai l the clinical course of a pediatr ic pat ient with cryptogenic cirrhosis and a more severe degree of hypoxemia caused by in t rapu lmonary shunting, who underwent a successful liver t ransplanta t ion result ing in complete reversal of shunting.

Purpose: PDGF is a pro-inflammatory protein produced abundantly in allografts during chronic rejection. PDGF has been found to play important role in the recruitment of intragraft fibroblasts (IF). This study further investigated the act of PDGF on MCP-1 production by IF and its downstream effect on monocyte/macrophages. Methods and Materials: Intragraft fibroblasts derived from heart allografts undergoing chronic rejection were examined for production of a penal of pro-inflammatory cytokines, including MCP-1. The effect of PDGF on production of MCP-1 by IF, and consequential macrophage activation were studied using a fibroblast-macrophage co-culture system and a siRNA technology. Results: Quantitative real-time PCR demonstrated that fibroblasts from chronically rejecting allografts significantly increased expression of MCP-1 by 12 folds when compared with that from non-rejecting grafts (p 0.01). In serum-free condition cultures, PDGF significantly up-regulated expression of MCP-1 and PDGF receptor-beta by intragraft fibroblasts as well as by a fibroblast progenitor cell line Ap8c3. In transwell co-cultures, intragraft fibroblasts activated macrophage cell line J774, as demonstrated by a significant increase in expression of MCP-1 receptor CCR2, and promoted proliferation of the macrophages. MCP-1 siRNA treatment of IF resulted in significant decrease in MCP-1 production and suppression of CCR2 expression by J774 cells in co-cultures. MCP-1 siRNA treatment of IF consequently inhibited J774 proliferation. (p 0.01). Conclusions: Intragraft fibroblasts and macrophages are regulated by a complex network of pro-fibrogenic/inflammatory cytokines. This mechanistic study suggests that a pathway involving PDGF, MCP-1 and their receptors play an important role in the recruitment of macrophages into allografts during chronic rejection.

Liver transplantation is widely used as a treatment for end-stage liver disease. Liver allografts seem privileged compared with other solid organ grafts for a number of reasons. Successful liver transplantation can be performed across major histocompatibility complex (MHC) disparities, and the liver is the only solid organ that, when transplanted, can protect other co-transplanted syngeneic organs from immunological tissue destruction [1]. A proportion of patients with stable function can have immunosuppression reduced or withdrawn completely [2,3]. The reasons for this "liver effect" are not understood. Recently, there has been interest in lymphocyte apoptosis that occurs in OLT animal models. Allograft tolerance can be readily induced in experimental animals, particularly rodents, and spontaneous tolerance of mismatched liver grafts occurs in some train combinations [4]. In a spontaneously tolerant murine model of liver transplantation, the development of tolerance was associated with a higher rate of apoptosis of cells in the portal inflammatory infiltrate [5]. Sharland et al. [6], in a rat model, also showed that tolerant animals had higher numbers of apoptotic cells; they demonstrated by double staining that these were T lymphocytes. Kupffer cells (KC), the resident macrophage population in the liver, are found within the sinusoidal lumen, adhering to the liver sinusoidal endothelial cells (LSEC). KC, which comprise one of major populations (20%) of the hepatic nonparenchymal cell fraction (NPC), can directly interact with passenger leukocytes and thus may play a role in immunomodulation and the induction of tolerance [7]. Following liver transplantation, donor KC not only migrate into the recipient lymph nodes, but also can be quickly replaced by recipient-derived monocytes [8,9]. Thus, KC are uniquely positioned for regulation of the T cell response in the liver. Our previous studies have shown that KC play an immunomodulatory role as manifested by inhibiting T lymphocyte proliferation in response to alloantigen stimulation. The purpose of this study was to quantify the effects of liver transplantation on KC immunomodulatory function, focusing specifically on Fas ligand (FasL) expression and their role in allo-reactive T cell apoptosis in chronic accepted and acutely rejected hepatic allografts.

of endotoxemia show depression of hepatic phagocytosis of radiolabeled particles. Here we investigated the effect of LPS on the hepatic clearance and killing of tracer doses of live, circulating E. coil, and evaluated the roles of neutrophils and TNFct in mediating this effect. Methods: We employed a validated method for discriminantly quantitating the clearance of live, double-radiolabeled, circulating E. coil and the subsequent killing of those bacteria in C57B1/6 mice (J Leek Bio155:248-252:94). Results: Administration of intraperitoneal LPS (0.01-2.0mg/kg) effected doseand time-dependent decreases of the hepatic clearance and killing efficiency of circulating E. coll. This effect was maximal at lmg/kg LPS 4h after injection. Hepatic clearance was reduced from 75 ±4% to 63 ± 3% (p

Background: A functional hepatic reticuloendothelial system (RES) is important for host defense against circulating microorganisms. Although the relationship between hepatic ischemia/reperft~sion (I/R) and hepatic injury via neutrophil accumulation is reported, alterations of RES function after hepatic I/R are less well characterized. This study was designed to: A) quantify the alterations in RES function after I/R and B) determine the mechanism and effect of neutrophil accumulation on RES function after I/R. Methods: In control mice, the blood supply to the left lateral hepatic lobe was occluded for 45m, after which the liver was reperfused. Experimental mice were pre-treated with either vinblastin (1.5mg/kg) to induce neutropenia or anti-P selectin (50lag/mice) to block initial neutrophil adhesion, 4 days and 5 min before ischemia, respectively. RES function was measured 1, 4 and 24h after reperfusion using the quantitatively validated, double-labeled (51Cr and 125I-UdR) E.coli method (J Leukoc Biol 55:248, 1994). In each case the nonischemic lobe served as a control for I/R. Results: 1) Hepatic phagocytic clearance and hepatic killing efficiency were reduced by I/R and restored by either neutropenia ( < 2 x 102/ram -~) or anti-P selectin in both the ischemic and the adjacent non-ischemic lobes. 2) This hepatic RES function reached a nadir 4h after hepatic I/R. This time point correlated with the peak of MPO activity in liver, which was blocked by anti-P selectin. 3) RES dysfunction after I/R was attenuated by either neutropenia or anti-P selectin.

Factor XI deficiency (the Rosenthal syndrome), an autosomal recessive genetic defect, was transmitted to a patient after orthotopic liver transplantation. The deficiency was manifested by an isolated prolonged activated partial thromboplastin time (aPTT) after surgery. Hematologic evaluation using specific factor analysis revealed an absolute deficiency of factor XI. Stored serum obtained from the organ recipient before transplantation showed normal factor XI levels. When the liver donor's family was questioned, it was discovered that he was of Ashkenazi Jewish descent and that he had a history of bleeding after dental procedures. Before his death from intracerebral bleeding, he was documented to have an isolated prolonged aPTT value. This case shows that potentially morbid genetic defects can be transmitted by organ transplantation. It also provides evidence confirming that the liver is the only site of factor XI production.

Fifteen patients who had a prior portasystemic shunt underwent orthotopic liver transplantation. Shunt types were portacaval in six patients, H-graft mesocaval in six, distal splenorenal in two, and proximal splenorenal in one. Mean blood loss and hospital stay were highest in the portacaval group. Retransplants (two patients) and deaths (two patients) also were limited to this group. In this report, technical considerations, advantages, and disadvantages of the various shunt types are described. Management of patients with late stages of portal hypertension must include estimation of the effects of a portasystemic shunt on subsequent liver transplantation. It is concluded that portacaval shunts should be avoided in patients who may be considered for transplantation. Distal splenorenal shunts are best performed in younger patients with intractable variceal bleeding who are not expected to require transplantation in the near future. A mesocaval H-graft is the shunt of choice in patients who are current liver transplant candidates.

Fatal mushroom poisoning has long been recognized as a major health problem in western Europe and more recently in the United States. The majority of deaths are attributable to the genus Amanita. Amanita phalloides (death cap) has been found with increasing frequency across the United States and presents a significant health hazard in this country to those who pick and consume wild mushrooms. This article discusses the pharmacologic basis and clinical manifestations of Amanita intoxication. It outlines the rationale of various treatment modalities and, from these, summarizes a protocol that the authors believe will be useful to the clinician. In addition, two patients are presented who underwent successful orthotopic liver transplantation for fulminant hepatic failure secondary to Amanita poisoning. The role of liver transplantation both acutely and as treatment for chronic active hepatitis secondary to severe intoxication is discussed.