Fulminant liver failure due to usnic acid for weight loss

The use of complementary and alternative medicine (CAM) in developed countries has increased significantly over the years. Among the most popular are the weight loss supplements or "fat burners." Liver failure due to these popular remedies has been widely recognized. Usnic acid has been an ingredient of dietary supplements that cause liver failure. Its hepatotoxicity has not been recognized because it is usually mixed with other ingredients that are presumably hepatotoxic. We describe a case of a 28-yr-old woman who presented with fulminant liver failure requiring orthotopic liver transplantation, after taking pure usnic acid for weight loss. This is the first report on fulminant liver failure associated with the ingestion of pure usnic acid. A discussion about hepatotoxicity of the different compounds of dietary supplements is presented. This is a reminder for the clinicians about the potential side effects of CAM.

MELD scores of liver transplant recipients according to size of waiting list: impact of organ allocation and patient outcomes

CONTEXT

The Model for Endstage Liver Disease (MELD) score serves as the basis for the distribution of deceased-donor (DD) livers and was developed in response to "the final rule" mandate, whose stated principle is to allocate livers according to a patient's medical need, with less emphasis on keeping organs in the local procurement area. However, in selected areas of the United States, organs are kept in organ procurement organizations (OPOs) with small waiting lists and transplanted into less-sick patients instead of being allocated to sicker patients in nearby transplant centers in OPOs with large waiting lists.

OBJECTIVE

To determine whether there is a difference in MELD scores for liver transplant recipients receiving transplants in small vs large OPOs.

DESIGN AND SETTING

Retrospective review of the US Scientific Registry of Transplant Recipients between February 28, 2002, and March 31, 2003. Transplant recipients (N = 4798) had end-stage liver disease and received DD livers.

MAIN OUTCOME MEASURES

MELD score distribution (range, 6-40), graft survival, and patient survival for liver transplant recipients in small (<100) and large (> or =100 on the waiting list) OPOs.

RESULTS

The distribution of MELD scores was the same in large and small OPOs; 92% had a MELD score of 18 or less, 7% had a MELD score between 19 and 24, and only 2% of listed patients had a MELD score higher than 24 (P =.85). The proportion of patients receiving transplants in small OPOs and with a MELD score higher than 24 was significantly lower than that in large OPOs (19% vs 49%; P<.001). Patient survival rates at 1 year after transplantation for small OPOs (86.4%) and large OPOs (86.6%) were not statistically different (P =.59), and neither were graft survival rates in small OPOs (80.1%) and large OPOs (81.3%) (P =.80).

CONCLUSIONS

There is a significant disparity in MELD scores in liver transplant recipients in small vs large OPOs; fewer transplant recipients in small OPOs have severe liver disease (MELD score >24). This disparity does not reflect the stated goals of the current allocation policy, which is to distribute livers according to a patient's medical need, with less emphasis on keeping organs in the local procurement area.

Molecular adsorbent and re-circulating system

The molecular adsorbent recirculating system (MARS) is a non-biological artificial liver support system. Used for almost a decade, there are only two randomized controlled trials on the efficacy of MARS till date. A number of uncontrolled studies have documented a marked improvement in the biochemical parameters of patients after MARS. Although MARS seems to be an effective and promising tool in the management of liver failure, its cost needs to be reduced to enable it use in a member of indications.

Prevention of Fas-mediated hepatic failure by transferrin

Recent studies in lymphohemopoietic cells show that transferrin (Tf), a pivotal component of iron transport and metabolism, also exerts cytoprotective functions. We show here in a murine model that Tf interferes with Fas-mediated hepatocyte death and liver failure. The mechanism involves the downregulation of apoptosis via BID, cytochrome c, caspase-3 and caspase-9, and upregulation of antiapoptotic signals via Bcl-xL. The results obtained with iron-saturated Tf, Apo-Tf and the iron-chelator salicylaldehyde isonicotinoyl hydrazone indicate that the observed antiapoptotic effect of Tf was not mediated by iron alone. In conclusion, the data suggest that Tf has broader functions than previously recognized and may serve as a cytoprotective agent.

Standardization of ischemic hepatic failure in pigs as a model for bioartificial liver assessment

PURPOSE

A standard protocol of ischemic liver failure in pigs was examined to establish a system for assessing the efficacy of a bioartificial liver, based on clinical practice.

METHODS

The portal blood flow was extracorporeally bypassed into the cervical jugular vein, using a centrifugal blood pump. The portal vein and hepatic artery were then ligated.

RESULTS

The maintenance protocol was established as follows: (1) the concentration of the inhaled anesthetic was decreased by 0.2% when the systolic blood pressure was <100 mmHg; (2) the volume of an infusion containing 5% glucose was increased to 10 ml/kg per hour when central venous pressure was <5 mmHg; (3) 20 ml of 50% glucose was injected intravenously when the blood glucose was <50 mg/dl; (4) 2000 units of heparin was injected intravenously when the activated clotting time was <150 s; (5) sodium bicarbonate was given when the blood pH was <7.3; (6) tidal volume was increased by 1 ml/kg when the pCO(2) was >80 mmHg; (7) oxygen was increased by 25% when the pO(2) was <100 mmHg. No vasopressors were used in the experiment.

CONCLUSION

Our protocol reduced the operating time and minimized the risk of data deviation that can arise from variations in operating techniques and individual animal conditions. This experimental model is also easy to use as a bridge to transplantation.

Up-regulation of hepatocyte growth factor caused by an over-expression of transforming growth factor beta, in the rat model of fulminant hepatic failure

BACKGROUND

The role of transforming growth factor beta (TGF-beta), a potent regulator of cellular growth, was investigated in the rat model of fulminant hepatic failure (FHF).

MATERIALS AND METHODS

The rat FHF model was created by a combination of a 68% partial hepatectomy (PH) and 7% of necrosis (each n = 25 in Groups 1, 2 and 3). Adenovirus mediated gene transfer of mature human TGF-beta1 gene was performed by the systemic injection of AxCAhTGFb1 (1 x 10(9) pfu) in Group 1, 3 days before FHF. In control Groups 2 and 3, recombinant lacZ adenovirus (AxCAlacZ, Group 2) and normal saline (1 ml, Group 3) were used, instead of AxCAhTGFb1.

RESULTS

An excessive expression of TGF-beta1 in Group 1 resulted in an inhibition of hepatocyte proliferation (24-48 h after FHF) and gaining of liver weight (24-48 h), increased expression of HGF in liver tissue (24 h), and decreased expression of TGF-alpha (24 h), compared to those in control Groups 2 and 3. Serum IL-6 levels were also elevated by a TGF-beta1 over-expression at 24 hrs after FHF in Group 1.

CONCLUSIONS

The forced expression of TGF-beta1 in the FHF liver yields both a secondary increase of HGF production and a suppression of liver regeneration, which might explain the mechanism of increased serum HGF observed in a clinical FHF. TGF-beta1 is thus thought to have an important role in inhibiting liver regeneration after FHF.

Patient Selection for Left Ventricular Assist Devices

The use of mechanical support as a bridge to cardiac transplant has become the standard of care in many cardiac transplant centers. This therapy has been shown to increase survival and improve morbidity in carefully selected patients waiting for heart transplantation. With approximately 30000 patients being listed worldwide for transplant every year and only 3500 transplantations performed annually, alternative strategies need to be developed to minimize morbidity and mortality in this high-risk population. Patient selection remains the primary determinant of success with left ventricular assist device (LVAD) therapy. This article will review both the cardiac and extracardiac considerations needed in the assessment of patient suitability for LVAD support as a bridge to transplantation.

Scintigraphic study of regenerative nodules due to fulminant hepatic failure

We report the case of a 25-year-old woman with fulminant hepatic failure (FHF). Liver scintigraphy using (99m)Tc-galactosyl human serum albumin (GSA) and (99m)Tc-phytate produced interesting findings; regenerative nodules appeared as nodules of increased accumulation of (99m)Tc-GSA, whereas these nodules were expressed as defects of accumulation of (99m)Tc-phytate. These scintigraphic findings suggested that the functions of hepatocytes in regenerative nodules were maintained, whereas those of Kupffer cells were impaired. Although (99m)Tc-GSA scintigraphy indicated hepatic functional reserve enough to survive, she died despite intensive therapy including plasma exchange. Based on this case, it is recommended that not only (99m)Tc-GSA scintigraphy but also (99m)Tc-phytate scintigraphy is required to evaluate the prognosis of patients with FHF.

Caspase-dependent apoptosis in fulminant hepatic failure induced by herpes simplex virus in mice

BACKGROUND/AIMS

Herpes simplex virus (HSV) is known to induce fulminant hepatic failure. The aim of this study is to clarify the molecular basis of liver injury in HSV-induced hepatitis.

METHODS

Immunocompetent mice were inoculated with HSV or ultraviolet-inactivated HSV (UV-HSV) intravenously. Extent of liver injury was evaluated by changes of serum enzymes and histopathology. Apoptosis was assessed by DNA fragmentation and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). Immunohistochemistry for caspase-3 and Fas ligand was performed. Reverse transcriptase-polymerase chain reaction for Fas ligand was also performed.

RESULTS

All mice died of rapid and massive liver cell death after HSV infection, whereas no change was observed in mice after UV-HSV inoculation. The extent of viral replication and DNA fragmentation correlated well with the severity of liver injury. Caspase-3 was activated in the liver after HSV infection, but not UV-HSV. Positive reaction for TUNEL was observed not only in HSV-antigen positive cells but also in HSV-antigen negative cells. Fas ligand was induced in the liver infected with HSV, but not with UV-HSV.

CONCLUSIONS

Caspase-dependent apoptosis is involved in HSV-associated liver injury. Not only viral replication but also non-viral factor such as Fas ligand may facilitate rapid development of this disease.

Extracorporeal liver support based on primary human liver cells and albumin dialysis--treatment of a patient with primary graft non-function

METHODS

Following liver transplantation, a 26-year old female suffered from primary non-function of the transplant. The patient was subsequently treated with a modular extracorporeal liver support concept until a suitable organ became available. A bioreactor was charged with human liver cells, obtained from a discarded cadaveric graft (470 g, viability: 60%). The bioreactor was integrated into an extracorporeal circuit with continuous single pass albumin dialysis and continuous veno-venuous hemodiafiltration for detoxification and fluid reduction.

RESULTS

Over the total system application time of 79 h, a significant reduction of the plasma levels of total bilirubin (21.1 mg/dl at start, 10.1 mg/dl at end of therapy) and ammonia (100 versus 22.7 micromol/l) was achieved. During treatment the patient's neurological status significantly improved from coma stage IV to I permitting extubation. Recovery of kidney function with a urine output of 1325 ml/24 h compared to 45 ml/24 h prior to system application, was noted. Over the treatment period, an improvement of coagulation status was observed. Adverse events were absent.

CONCLUSIONS

This first successful clinical treatment of a patient with liver failure suggests that a modular approach combining both primary human liver cell bioreactor technology and detoxification methods is promising.

Granulocyte-colony stimulating factor administration ameliorates liver regeneration in animal model of fulminant hepatic failure and encephalopathy

It has previously been shown that recombinant granulocyte-colony stimulating factor (rG-CSF) accelerates and enhances hepatocyte proliferation in partially hepatectomized rats. In the present study, we examined the effect of rG-CSF administration on liver injury, regeneration, and survival outcome in an experimental rat model of fulminant hepatic failure (FHF) and encephalopathy induced by repeated injections of thioacetamide (TAA). FHF was induced in adult male Wistar rats by three consecutive intraperitoneal injections of TAA, at intervals of 24 hr. The animals were also injected with either saline or rG-CSF. Serum biochemical parameters and blood ammonia levels, liver histology, stage of hepatic encephalopathy, and survival were statistically significantly improved in TAA-intoxicated and rG-CSF-treated rats compared to TAA-intoxicated and saline-treated ones. Furthermore, rG-CSF not only ameliorated the histologically evident liver injury in a statistically significant manner but also enhanced the proliferative capacity of the hepatocytes. Our data confirm the beneficial effect of rG-CSF administration in this animal model of FHF and encephalopathy, supporting evidence for a possible use of rG-CSF as supportive therapy in the management of FHF.

Significance of and contributing factors for a high resistive index on Doppler sonography of the hepatic artery immediately after surgery: prognostic implications for liver transplant recipients

OBJECTIVE

The goal of our study was to investigate the contributing factors, clinical repercussions, and implications for prognosis of high-resistance flow at the hepatic artery detected on Doppler sonography during the period immediately after orthotopic liver transplantation.

MATERIALS AND METHODS

We retrospectively studied the transplanted livers of 90 patients who had been examined on Doppler sonography within the first 3 days after grafting. Seventeen variables from organ donors, transplant recipients, graft characteristics, and surgical procedures were investigated. Early clinical evolution was also analyzed. Follow-up was performed for 5 years.

RESULTS

Forty-one (45.6%) of the 90 patients showed a high resistive index at the hepatic artery during the first 72 hr after transplantation. Two factors showed a statistically significant effect on the occurrence of a high resistive index at the hepatic artery immediately after transplantation: an older liver donor (p = 0.008) and extended preservation time (p = 0.005). No relation with early graft function was detected. The incidence of bile duct complications, retransplantation, or death was not higher at follow-up in patients with high-resistance flow than in those with normal flow.

CONCLUSION

High-resistance flow at the hepatic artery detected on Doppler sonography during the period immediately after transplantation is a frequent finding and is related to older donor age and prolonged period of ischemia. This finding has neither significant clinical repercussions nor prognosis implications for early and long-term follow-up.

Liver failure: basis of benefit of therapy with the molecular adsorbents recirculating system

Accumulation of albumin-bound toxins is known to occur in liver failure, and to variable extents is responsible for the associated end-organ dysfunctions (kidney, circulation, brain). The toxin-binding and scavenging functions of albumin are exploited in albumin dialysis for removal of these toxins. The extracorporeal liver support device known as molecular adsorbents recirculating system (MARS) is based on dialysis across an albumin-impregnated membrane, using 20% albumin as dialysate. Charcoal and anion exchange resin columns in the circuit help cleanse and regenerate the dialysate. Clinical studies over the last few years have demonstrated proven reduction in hyperbilirubinaemia, along with an improvement in encephalopathy, systemic haemodynamics and renal function in liver failure patients, as well as apparent improvement in survival. The results of larger controlled clinical trials, as well as studies investigating the pathophysiological basis of its effect, are awaited.

Autonomic neuropathy is associated with hemodynamic instability during human liver transplantation

INTRODUCTION

End-stage liver disease is frequently associated with autonomic neuropathy (AN). The hemodynamic changes during liver transplantation (LT) require an adequate autonomic response to maintain cardiovascular stability.

PATIENTS AND METHODS

Forty-one patients undergoing LT were evaluated for the influence of AN on the evolution after LT. AN was previously evaluated by seven cardiovascular tests assessing sympathetic (Sy) or parasympathetic (P) function. Patients were classified as absent (A), early (E), or definite dysfunction (D). A hemodynamic study was performed before and after vascular clampings. The analysis included the duration of LT, transfusion requirements, intra-operative artenal hypotensive episodes, incidence of postreperfusion syndrome (PRS), cardiac arrhythmias and vasoactive drug requirements.

RESULTS

The hyperdynamic circulation worsened during surgery in D patients, as shown by a significantly increased cardiac output and a significantly decreased systemic vascular resistance. The incidence of PRS was greater in the AN group. Arterial hypotension during the neohepatic period was more frequent among patients with AN, more frequently requiring vasoconstrictor and inotropic therapy.

CONCLUSIONS

AN is associated with hemodynamic impairment and with increased vasoactive drug requirements during liver transplantation, probably associated with impaired reflex vasoconstrictor responses to surgical manipulations and changes of blood volume. AN may be associated with a greater surgical risk during LT. Preoperative evaluation of AN may select a high-risk population of LT recipients.

Liver transplantation for fulminant and subfulminant hepatic failure

AIMS

The aim of this study was to assess the long-term course and outcome after liver transplantation (LTX) for fulminant/subfulminant hepatic failure (FSHF) to determine which factors relate to outcome.

PATIENTS AND METHODS

Between April 1990 and October 2002, 30 adult patients with FSHF underwent LTX. King's College criteria were used to decide which patients needed LTX. Pretransplantation parameters (age, sex, degree of hepatic encephalopathy, etiology, and time between onset of symptoms and LTX) were examined as risk factors for LTX outcome.

RESULTS

Mean age at LTX was 40.4+/-13.9 years and 46.7% were men. The most frequent causes of FSHF were virus B in 23.3%, autoimmune hepatitis in 23.3%, and cryptogenic in 20%. Fifty percent of the patients with a survival longer than 15 days suffered episodes of acute rejection; chronic rejection occurred in 25%. One- and five-year patient and allograft survival rates for FSHF were 56.3% and 54.7%, respectively. Autoimmune hepatitis was the only factor associated with better posttransplantation outcome, although there were no differences in posttransplant course. Patient survival rates increased during the study period. During the first 5 years (1990-1995) the survival rates were 53.3% (1-year and 5-year), whereas they were 60% at 1 and 5 years in the second interval (1996-2002).

CONCLUSIONS

The mortality rate of FSHF is high during the first year post-LTX. LTX for FSHF of autoimmune etiology showed better outcomes with increasing patient survival rates during the study period.

Interleukin 6/gp130-dependent pathways are protective during chronic liver diseases

The contribution of the acute phase inducer interleukin 6 (IL-6) in the pathogenesis of liver diseases is yet unclear. Our analysis showed enhanced expression of IL-6 in livers derived from patients with acute and chronic liver diseases. Additionally, IL-6 plasma levels were significantly increased in patients with chronic liver diseases and showed an inverse correlation with biochemical markers of liver function and a positive correlation with inflammatory markers, signs of portal hypertension, and the degree of liver fibrosis. To prove the relevance of these clinical findings, we applied the tetrachlorcarbonide (CCl(4)) model to conditional knockout animals (Cre/loxP system) for gp130, the common signal transducer of IL-6 family cytokines. Cre recombinases were expressed through a hepatocyte (AlfpCre) and a ubiquitous (MxCre) control element. Gp130 deleted mice had a totally abolished STAT3 activation and acute phase response induction, but gp130 deletion had no effect on the degree of acute liver injury and subsequent hepatocyte proliferation. In contrast, during chronic liver injury induced by biweekly application of CCl(4), deletion of the gp130 receptor in nonparenchymal liver cells and not hepatocytes resulted in fibrosis progression. In conclusion, our experiments indicate an involvement of IL-6 in the pathogenesis of liver diseases and suggest a protective role of IL-6/gp130-dependent pathways in nonparenchymal liver cells during fibrosis progression in chronic liver diseases. (Hepatology 2003;38:218-229).

Hepatic regeneration: If it ain't broke, don't fix it

The capacity for the liver to regenerate after injury or resection has long been recognized, as implied by the legend of Prometheus. Resections of up to 70% of the liver are followed by a sequence of events that generally result in complete restitution of hepatic mass and function. Hypertrophy of hepatocytes begins within hours, with accumulation of amino acids and triglycerides and activation of enzymes that are associated with proliferative activity. Increased DNA synthesis is associated initially with hyperplasia of hepatocytes, and then other cells, which begins in the periportal region and spreads in a wave-like fashion to the pericentral region of the lobule. Quiescent hepatocytes are primed to enter the cell cycle and then proceed through the G1/S and G2/M restriction points, under the influence of a variety of proteins, growth factors (especially hepatocyte growth factor) and cycle dependent kinases. At each stage there is interplay between growth promoters and inhibitors, including transforming growth factor-beta and GABA. Factors that initiate hepatic regeneration are unknown, and might include hepatic depolarization, increases in blood flow, destruction of liver matrix (with release of growth factors), and increased production or expression of growth promoters compared to inhibitors. Regenerative activity increases with the amount of resection to a point, and then relatively declines. Uncontrolled proliferation of liver tissue after resection or injury is not necessarily beneficial, because it could lead to a diversion of resources from the maintenance of hepatic function and to an increased risk of neoplasia. Therefore, it is unclear whether clinicians should attempt to enhance hepatocyte regeneration. Since both hepatic regeneration and metabolic function require energy from high-energy nucleotide triphosphates, especially adenosine triphosphate (ATP), a reasonable strategy might be to augment energy delivery and ATP production. Mortality rates after limited (fewer than 70%) resections and mild or moderate injuries of previously normal livers are low, and supportive care is often sufficient. The prognosis is unclear; however, in cases of more massive resection, resections in the setting of underlying liver disease or cirrhosis, and fulminant hepatic failure, and liver transplantation is still an important option.

Liver transplantation in acute liver failure

Acetaminophen and idiosyncratic drug induced hepatotoxicity are the most commonly identified etiologies of acute liver failure in Western countries. Infectious complications and cerebral edema remain the leading causes of death. Moderate hypothermia and other medical interventions may improve cerebral edema in selected patients with acute liver failure. In addition, pilot studies suggest that recombinant factor VIIa infusions may allow for the safe placement of intracranial pressure monitoring devices in patients with cerebral edema and severe coagulopathy. Auxiliary liver transplantation and bioartificial liver devices offer the hope of temporary liver support for selected patients with a high likelihood of native liver regeneration. Prognostic survival models that include arterial lactate levels may improve our ability to identify acetaminophen overdose patients in urgent need of liver transplantation. The lower 1-year patient survival following liver transplantation for acute liver failure compared to chronic liver failure (60 vs 80%) is in part due to the emergent nature of surgery, concomitant vital organ failure, and the higher incidence of immunologically mediated graft dysfunction. Vaccination against hepatotrophic viruses and other public health measures designed to minimize the incidence of both intentional and non-intentional acetaminophen overdose may help reduce the future incidence of acute liver failure. In the meanwhile, it is recommended that acute liver failure patients be managed in experienced centers with ready access to liver transplantation to optimize outcomes in this rare but frequently fatal illness.

Hepatobiliary nutrition: history and future

The liver is a master metabolic gland; consequently, liver disease commonly results in significant malnutrition. Complex metabolic derangements always accompany liver failure, often reflect the magnitude of hepatic insufficiency, and are characterized by accentuated catabolism. Nutritional assessment is problematic in these patients, because many of the usual indicators of nutritional status are altered directly by the hepatic pathophysiology rather than, or in addition to, preexisting or subsequent secondary malnutrition. The objective of nutritional support in patients with liver failure is to provide adequate nutrients to ensure the availability of specific substrates for energy and protein synthesis and for normal hepatocyte survival and function, without inducing or accentuating encephalopathy or otherwise compounding hepatic insufficiency. In the near future, guidelines must be developed for the specific nutritional support of patients with fulminant hepatic failure, cholestatic liver disease, steatosis, and cirrhosis. Currently, work is underway to develop an artificial liver for patients awaiting transplantation; to use genetic engineering technology to provide an alternative source of hepatic tissue; and to test the utility of various intermediary metabolites for hepatobiliary nutrition support. No ideal regimen for nutritional support of all forms of liver failure exists, and this also represents a significant challenge for future basic and clinical investigations. However, it is mandatory to attempt to maintain optimal nutrition in patients with severe liver failure if morbidity and mortality are to be reduced and survival is to be maximized.