Acute liver failure

Decreased plasma gelsolin concentrations in acute liver failure, myocardial infarction, septic shock, and myonecrosis

OBJECTIVE

To quantitate gelsolin concentrations in serum of patients with a variety of conditions involving actin release into the circulation.

DESIGN

Prospective evaluation of sera on consecutive patients.

SETTING

Metropolitan county hospital.

PATIENTS

Ninety hospital patients with a variety of well-characterized diseases.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Sera were studied from patients with acute liver failure (n = 18), chronic hepatitis (n = 17), cirrhosis of varying etiology (n = 17), pancreatitis (n = 10), acute myocardial infarction (n = 10), myonecrosis due either to polymyositis or crush injuries (n = 12), and septic shock (n = 6); results were compared with sera from healthy individuals (n = 25). Gelsolin was quantified by Western blotting with monoclonal anti-gelsolin and laser densitometry. Significant reductions in mean gelsolin concentrations compared with healthy controls were observed in patients with acute liver failure (47%), myocardial infarction (69%), sepsis (51%), and myonecrosis (66%). An inverse correlation was observed between gelsolin concentration and severity of illness, as indicated by the magnitude of serum enzyme concentrations.

CONCLUSIONS

Gelsolin depletion occurs in a variety of tissue injury syndromes. Depletion of actin-scavenger capacity in the presence of continued actin release may affect outcome in situations of severe organ damage.

Liver function and splanchnic ischemia in critically ill patients

STUDY OBJECTIVE

To investigate the concept that splanchnic ischemia leads to hepatic dysfunction in the critically ill.

DESIGN

Prospective study and analysis of patient data.

SETTING

A general ICU in an inner-city London teaching hospital.

PATIENTS

Twenty-seven consecutive critically ill patients with evidence of inadequate tissue perfusion requiring pulmonary artery catheterization and mechanical ventilation.

MEASUREMENTS

In all patients, we measured the hepatic metabolism of lidocaine (lignocaine) to monoethylglycinexylidide (MEGX) and the clearance of indocyanine green (both dynamic, flow-dependent tests of hepatic function) over the first 3 days following admission to the ICU. These were compared with results of standard liver function tests and related to tonometric assessment of gastric intramucosal pH (pHim) and outcome.

RESULTS

There were no significant differences in bilirubin, aspartate aminotransferase, alkaline phosphatase, and prothrombin levels, or in indocyanine green clearance between survivors and nonsurvivors. On day 3, the median MEGX level was higher in survivors than in nonsurvivors (16 vs 2.4 ng/mL, p < 0.001), and the median MEGX level in nonsurvivors fell over the 3 days (20.6 to 2.4 ng/mL, p < 0.002). MEGX levels were significantly correlated with pHim (Spearman rank correlation coefficient [Rs] = 0.69, p < 0.001) as were the changes in the two measurements over the 3 days (Rs = 0.46, p < 0.02). The MEGX formation test and gastric pHim were the most discriminatory with regard to death and survival.

CONCLUSIONS

Our findings suggest that critically ill patients develop significant hepatic dysfunction that is associated with a poor outcome. This is likely to be due to a mismatch between hepatic metabolic demand and blood flow, and the MEGX formation test appears to be an extremely effective means of assessing liver function and flow in this group of patients.

Early indicators of prognosis in fulminant hepatic failure: an assessment of the King's criteria

BACKGROUND/AIMS

An accurate and early assessment of the individual patient is critical in deciding whether liver transplantation is indicated in the treatment of fulminant hepatic failure. Based on analysis of patients treated between 1973 and 1985, the Liver Unit at King's College Hospital, London, developed a prognostic model to identify patients with a poor prognosis. The present study was done to determine the applicability of this model in fulminant hepatic failure patients seen at our center in the 1990s.

METHODS

The records of 145 patients with fulminant hepatic failure, treated conservatively at Queen Elizabeth Hospital, Birmingham between 1990 and 1994, were analyzed. An additional 81 patients, who were transplanted for fulminant hepatic failure during the same period were excluded from the study.

RESULTS

Application of King's College Hospital criteria at the time of admission to this hospital in the acetaminophen group, had a positive predictive value of 88%, negative predictive value of 65% and predictive accuracy of 71%. The positive predictive value, negative predictive value and predictive accuracy of these criteria for non-acetaminophen-induced fulminant hepatic failure, were 79%, 50% and 68%. Multivariate analysis identified prothrombin time, serum creatinine, white cell count and abnormal potassium levels as independent predictors of mortality in acetaminophen-induced fulminant hepatic failure; and prothrombin time alone in fulminant hepatic failure induced by other etiologies.

CONCLUSIONS

The King's College Hospital criteria for predicting outcome of fulminant hepatic failure were found to have a slightly lower predictive accuracy than shown in the original study.

Auxiliary partial orthotopic liver transplantation for fulminant hepatitis. The Paul Brousse experience

OBJECTIVE

The authors objective is to report their experience with auxiliary partial orthotopic liver transplantation in fulminant hepatitis (FH) and to discuss the principles that may help in its safe application.

SUMMARY BACKGROUND DATA

Auxiliary partial orthotopic liver transplantation is an attractive therapeutic method in FH because it provides hepatic function, whereas the remaining native liver is given the possibility to recover. Despite early encouraging reports, its place in the treatment of FH remains to be defined.

METHODS

Evaluation of 5 cases of FH treated with auxiliary partial orthotopic liver transplantation from a collective of 22 transplantations for 35 cases of FH referred to the authors' center from January 1994 to November 1995. The grafts were one left lobe, two left livers, and two right livers.

RESULTS

The native liver regenerated in three patients: one with Reye's syndrome who died of irreversible neurologic damage, one with FH caused by the hepatitis B virus who is alive 20 months after ABO incompatible graft removal, and one with FH caused by the hepatitis A virus who had her graft removed at 4 months. In two patients, regeneration did not occur: one with drug-induced FH who died of sepsis 3 months after surgery and one with FH of unknown origin who was retransplanted with a standard liver transplantation at 4 months for uncontrollable biliary rejection of an ABO incompatible graft (alive at 10 months). Two of the three patients who survived suffered severe neurologic complications.

CONCLUSIONS

Auxiliary partial orthotopic liver transplantation is an attractive treatment for FH, especially in the presence of good prognostic factors for native liver regeneration: a young patient, rapid onset of the disease, and viral hepatitis. It should be considered cautiously in patients with advanced encephalopathy. By providing a smaller mass of liver tissue than with standard orthotopic liver transplantation, and as a more complex operative procedure, auxiliary partial orthotopic liver transplantation may not be as effective in arresting the progression of neurologic damage.

Is a clinical application of hybrid liver support systems limited by an initial disorder in cellular amino acid and alpha-keto acid metabolism, rather than by later gradual loss of primary hepatocyte function?

The in-vitro amino acid (AA) and alpha-keto acid (KA) metabolism of bioreactors initially seeded with 2.5 x 10(9) pig hepatocytes was investigated with a perfusion technique. Considerable changes in the culture medium concentrations of AA and KA were measured during the first days in culture. This is indicative of dynamic cellular metabolism in the initial phase. While the concentration of pyruvate decreased starting on the first day, alpha-ketoglutarate, alpha-ketoisocaproate, alpha-ketoisovalerate, and alpha-keto-beta-methyl-n-valerate were synthesized. The long term use of hepatocyte cultures in bioreactors and thus a desirable clinical hybrid liver support therapy appears to be possible since the hepatocytes switched, after 15 days in culture, to steady-state conditions with a stable amino acid turnover featuring general AA uptake accompanied by KA release. The release of branched chain KA, in particular that of alpha-ketoisocaproate, reflects an effective transamination activity in the bioreactor system. Primary pig hepatocytes cultivated in hybrid liver support systems for therapy of acute liver failure or as devices for bridging to liver transplantation can sustain amino acid metabolism for at least 30 days in vitro. However, an initial disorder following the cell isolation that is demonstrated may limit immediate utilization of the systems prior to the reorganisation of the cells to tissue-like structures in bioreactors.

Loss of resistance to murine hepatitis virus strain 3 infection after treatment with corticosteroids is associated with induction of macrophage procoagulant activity

Activation of the immune coagulation system has been implicated in the pathogenesis of liver injury following infection of inbred mice with murine hepatitis virus strain 3 (MHV-3). Following MHV-3 infection, macrophages isolated from MHV-3-susceptible and -semisusceptible inbred strains of mice express increased procoagulant activity (PCA), whereas macrophages from resistant strains express no increase in PCA over basal levels. The PCA induced by MHV-3 is a prothrombinase, encoded by the gene Fgl-2, which encodes a fibrinogen-like protein (musfiblp). In this study, MHV-3-resistant A/J mice treated with methylprednisolone prior to infection with MHV-3 developed elevated levels of alanine aminotransferase in serum and died within 10 days of infection, with histological findings of fulminant hepatitis. In vitro, macrophages isolated from A/J mice and pretreated with methylprednisolone produced a marked increase in functional PCA following infection with MHV-3. The PCA was shown to be a prothrombinase by its ability to cleave 125I-prothrombin. Northern blot analysis of RNA transcripts from these macrophages demonstrated increased transcription of the Fgl-2 gene relative to that in macrophages which had not been pretreated with methylprednisolone prior to MHV-3 infection. Methylprednisolone pretreatment of MHV-3-infected macrophages stabilized the Fgl-2 mRNA. Thus, loss of resistance to MHV-3 secondary to methylprednisolone therapy is associated with increased transcription and stability of Fgl-2 mRNA resulting in expression of the Fgl-2 gene product, musfiblp. These results provide further insight into mechanisms of PCA regulation in response to MHV-3 infection in inbred strains of mice.

Treatment of hepatic failure--1996: current concepts and progress toward liver dialysis

Liver failure, especially in its acute form, is a medical emergency that quickly leads to failure of multiple other organs. Many of these end-organ failures can be supported temporarily by drugs or medical devices, but the support is invariably short-lived if liver function is not restored. In most instances, liver function can only be restored by transplantation, although patients with acute disease have the potential to recover by regeneration ("spontaneous recovery"). Unfortunately, spontaneous recovery from acute liver failure is uncommon, so the two most important aspects of patient management are highly skilled intensive care and early recognition of patients in need of liver transplantation. Even under these circumstances, the mortality of liver failure remains high because we have no easy way of replacing liver function on demand and donor organs are becoming increasingly difficult to obtain in time. The development of techniques for liver assist offer the possibility that patients with liver failure will become a simple management problem, analogous to the options available in the treatment of acute and chronic renal failure.

Admission levels of serum Gc-globulin: predictive value in fulminant hepatic failure

Gc-globulin scavenges actin released from necrotic hepatocytes to the extracellular space. In 77 patients with fulminant hepatic failure (FHF) (excluding patients treated with liver transplantation), admission levels of serum Gc-globulin and degree of complexing with monomeric actin (complex ratio) were determined to evaluate their predictive values in relation to survival/nonsurvival. Gc-globulin levels were significantly reduced in 47 nonsurvivors, compared with 30 survivors (96 +/- 71 mg/L vs. 169 +/- 101 mg/L, P < .001), whereas the complex ratio in nonsurvivors did not differ significantly from that of survivors. Gc-globulin levels were significantly lower in 59 patients with non-acetaminophen-induced FHF, compared with 18 patients with acetaminophen-induced FHF (P < .01). Using a cutoff level of serum Gc-globulin of 100 mg/L, a lesser value correctly predicted nonsurvival in 79 percent of patients with non-acetaminophen-induced FHF, whereas a higher value predicted survival in 60 percent. In patients with acetaminophen-induced FHF, nonsurvival was correctly predicted in 100 percent of patients and survival in 53 percent. In comparison, the King's College Hospital (KCH) criteria correctly predicted nonsurvival and survival in 69 percent and 57 percent, respectively, of the same non-acetaminophen-induced FHF patients and in 60 percent and 38 percent, respectively, of the acetaminophen-induced FHF patients. Thus, in our study population, the predictive properties of Gc-globulin were in the same range as the KCH criteria. An advantage of Gc-globulin is that it gives an estimate of the outcome already on admission. Acute liver transplantation should be considered in FHF patients with Gc-globulin less than 100 mg/L.

Prevalence of hepatitis B or C virus infection in patients with fulminant viral hepatitis. An analysis using polymerase chain reaction

BACKGROUND/METHODS

The cause of fulminant hepatitis is still not fully understood. We studied 23 patients with fulminant hepatitis, using polymerase chain reaction to detect hepatitis virus genomes. Tests for HBsAg and IgM anti-HAV and IgM anti-HBc were performed in all patients. Serum samples were stored at -70 degrees C for later analysis of anti-HCV and hepatitis virus genomes such as hepatitis B virus, hepatitis C virus and hepatitis D virus.

RESULTS

Of 23 patients, 17 (74%) had HBV-DNA and two (9%) had HCV-RNA. No patient was positive for both viruses or positive for HDV-RNA. Serological tests indicated that two patients, negative for HBV-DNA and HCV-RNA, were positive for IgM anti-HAV. In contrast, 8 of 17 (47%) HBV-DNA positive patients were negative for both IgM anti-HBc and HBsAg in conjunction with low levels of viremia. Four patients were positive for anti-HCV, but only one was positive for HCV-RNA. One patient, positive for HCV-RNA, was negative for anti-HCV.

CONCLUSIONS

Our results indicate that analysis of hepatitis virus genomes using polymerase chain reaction allows accurate identification of the virus causing fulminant hepatitis.

Hyperglycemia-induced latent scurvy and atherosclerosis: the scorbutic-metaplasia hypothesis

Latent scurvy is characterized by a reversible atherosclerosis that closely resembles the clinical form of this disease. Acute scurvy is characterized by microvascular complications such as widespread capillary hemorrhaging. Vitamin C (ascorbate) is required for the synthesis of collagen, the protein most critical in the maintenance of vascular integrity. We suggest that in latent scurvy, large blood vessels use modified LDL--in particular lipoprotein(a)--in addition to collagen to maintain macrovascular integrity. By this mechanism, collagen is spared for the maintenance of capillaries, the sites of gas and nutrient exchange. The foam-cell phenotype of atherosclerosis is identified as a mesenchymal genetic program, regulated by the availability of ascorbate. When vitamin C is limited, foam cells develop and induce oxidative modification of LDL, thereby stabilizing large blood vessels via the deposition of LDL. The structural similarity between vitamin C and glucose suggests that hyperglycemia will inhibit cellular uptake of ascorbate, inducing local vitamin C deficiency.

How valid is emergency liver transplantation for acute liver necrosis in patients with multiple-organ failure?

Multiple-organ failure (MOF), defined as the failure of initially uninvolved organs, is the final step of definitive and massive liver necrosis. Emergency liver transplantation (ELT) has radically modified the outcome of acute liver failure and early primary graft failure, but the results of ELT in cases of MOF are unknown. From May 1988 to June 1993, 243 patients underwent a liver transplantation (LT). Thirty-seven patients (15.2%) who had an acute liver necrosis complicated by a MOF underwent an ELT. Twenty-one patients were children. An emergency retransplantation was performed in 16 patients. Three or 4 organ-system failures (OSF) were present in 13 patients. Before ELT, the mean Acute Physiology and Chronic Health Evaluation (APACHE) II score was 26.3 +/- 5.1. Six-month and 1-year survival rates were 37.8% and 25.9%, respectively, after ELT complicated by MOF, and 78% and 73.5%, respectively, in other cases of LT. Twenty-six patients had surgical complications (70%), whereas thirty-one patients had medical complications (84%). Twenty-two patients died during the postoperative period (60%). Before ELT, infection (P < .05), cardiovascular failure (P < .03), and more than two OSF (P < .05) were more frequent in patients who died after intervention. The APACHE II score (P < .05) and the length of stay in the intensive care unit before ELT (P < .05) were lower among survivors. In the context of liver allograft shortage, our results suggest that an ELT should not be performed in patients with cardiac failure, more than two OSF, or an APACHE II score higher than 30.

Pattern of disease after murine hepatitis virus strain 3 infection correlates with macrophage activation and not viral replication

Murine hepatitis virus strain (MHV-3) produces a strain-dependent pattern of disease which has been used as a model for fulminant viral hepatitis. This study was undertaken to examine whether there was a correlation between macrophage activation and susceptibility or resistance to MHV-3 infection. Peritoneal macrophages were isolated from resistant A/J and susceptible BALB/cJ mice and, following stimulation with MHV-3 or lipopolysaccharide (LPS), analyzed for transcription of mRNA and production of interleukin-1 (IL-1), tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta), mouse fibrinogen-like protein (musfiblp), tissue factor (TF), leukotriene B4, and prostaglandin E2 (PGE2). Macrophages from BALB/cJ mice produced greater amounts of IL-1, TNF-alpha, TGF-beta, leukotriene B4, and musfiblp following MHV-3 infection than macrophages from resistant A/J mice, whereas in response to LPS, equivalent amounts of IL-1, TNF-alpha, TGF-beta, and TF were produced by macrophages from both strains of mice. Levels of mRNA of IL-1, TNF-alpha, and musfiblp were greater and more persistent in BALB/cJ than in A/J macrophages, whereas the levels and kinetics of IL-1, TNF-alpha, and TF mRNA following LPS stimulation were identical in macrophages from both strains of mice. Levels of production of PGE2 by MHV-3-stimulated macrophages from resistant and susceptible mice were equivalent; however, the time course for induction of PGE2, differed, but the total quantity of PGE2 produced was insufficient to inhibit induction of musfiblp, a procoagulant known to correlate with development of fulminant hepatic necrosis in susceptible mice. These results demonstrate marked differences in production of inflammatory mediators to MHV-3 infection in macrophages from resistant A/J and susceptible BALB/cJ mice, which may explain the marked hepatic necrosis and fibrin deposition and account for the lethality of MHV-3 in susceptible mice.

Temporary heterotopic auxiliary liver transplantation for fulminant hepatitis B

BACKGROUND/AIMS

Orthotopic liver transplantation has been shown to improve survival in fulminant hepatic failure. However, after orthotopic liver transplantation life-long immunosuppression is necessary and graft complications may occur.

METHODS

We employed heterotopic auxiliary liver transplantation in a 26-year-old man with fulminant hepatic failure due to hepatitis B virus infection.

RESULTS

From a comatose state with seizures and decerebrate posturing, the patient woke up the day after heterotopic auxiliary liver transplantation. The graft functioned sufficiently. After 2 weeks, when peritonitis developed, immunosuppression was stopped since the native liver was recovering as shown by serial HIDA scans, liver biopsies, clotting parameters and serum bilirubin. When severe rejection of the graft developed 2 weeks later, and the peritonitis had been treated successfully, the native liver had recovered sufficiently to allow the graft to be removed. Now, more than 1 year after heterotopic auxiliary liver transplantation, the patient is free from medication and he is immune for hepatitis B virus, his liver tests have returned to normal and he has regained his normal life.

CONCLUSIONS

Temporary heterotopic auxiliary liver transplantation for fulminant hepatitis B is feasible.

The arterial ketone body ratio and serum alpha-fetoprotein level in patients with acute hepatic failure

Hepatocyte regeneration is essential for recovery in acute hepatic failure, although it requires a large amount of energy. The ratio of acetoacetate to beta-hydroxybutyrate in arterial blood has been reported to reflect the cellular energy charge of hepatocytes, and we proposed that the recovery of the ratio in the early days of acute hepatic failure is essential for survival. However, there is no report on any marker of regeneration to confirm this hypothesis. In this study, we have assessed this ratio and the serum alpha-fetoprotein level sequentially in 26 patients with acute hepatic failure. Ten patients recovered and 16 died. The arterial blood ketone body ratio 3 days after the onset of hepatic encephalopathy of grade II or more was below 0.6 in 15 of the 16 nonsurvivors, whereas that in the 10 survivors was above 0.6. There was a positive correlation between the arterial blood ketone body ratio and the maximal concentration of alpha-fetoprotein (r = 0.465, p < 0.02 by Student's t-test). These data indicate that the arterial blood ketone body ratio is a marker for the capacity of the liver to regenerate and for the prognosis in patients with acute hepatic failure: effective hepatocyte regeneration may be impossible if these metabolic changes in acute hepatic failure impair the hepatocyte energy charge severely.

Acute liver failure: results of a 5-year clinical protocol

This investigation summarizes and evaluates the results of a clinical protocol that we designed to care for patients with acute liver failure (ALF). Adult patients with ALF were enrolled in the protocol. Grade II portal-systemic encephalopathy prompted admission to the intensive care unit (ICU). Patients who met the clinical criterion were activated for liver transplantation. Intracranial pressure (ICP) was monitored in patients with grade III encephalopathy. An increase in ICP was treated with hyperventilation, diuretics, barbiturates, or a combination thereof. Survival was considered to have occurred if the patient left the hospital alive. Our series included 25 patients. Orthotopic liver transplantation (OLT) was performed on 19 patients, 12 of whom survived. Only 2 of 6 patients who did not undergo transplantation survived. Ten of 11 patients who underwent transplantation before reaching grade IV encephalopathy survived. Only 2 of 8 patients who underwent transplantation after reaching grade IV survived (P = .006). The causes of death included cerebral edema (3 patients), disseminated aspergillosis (3 patients), and other (5 patients). ICP was monitored in 11 patients. Increased pressure was documented by seven of the monitors placed. There was one focal hemorrhage secondary to a subdural monitor. Outcome is improved if transplantation occurs before grade IV encephalopathy. ICP monitoring can be accomplished without significant risk of hemorrhage. In our series, infection with aspergillus occurred frequently and with fatal outcome.

Transplantation for fulminant and subfulminant hepatic failure with preservation of portal and caval flow

This article describes experience with preservation of portal and caval flow during orthotopic liver transplantation (OLT) for fulminant or subfulminant hepatic failure (FSHF) as an alternative to venous bypass. As a modification of the standard procedure, hepatectomy and graft implantation were performed with preservation of caval patency in combination with a temporary portocaval shunt. From July 1991 to March 1994, 25 consecutive patients with FSHF underwent OLT with preservation of portal and caval flow. All patients had severe confusion (n = 9) or coma (n = 16) with a mean(s.d.) clotting factor V of 13(5) per cent and a mean(s.d.) serum bilirubin level of 408(151) mumol/l. During the anhepatic phase, haemodynamic data showed a preservation of cardiac filling pressure, mean arterial pressure, and renal perfusion pressure, while the mean(s.d.) urine flow was maintained at 182(120) ml/h. Venous bypass was not required. There were three (12 per cent) deaths after the operation, and all survivors made a full neurological recovery. Normal postoperative creatinine values allowed the early use of baseline immunosuppression. The authors conclude that, in patients with FSHF, successful liver transplantation can be achieved with this technical procedure.

Pemoline-associated fulminant liver failure: testing the evidence for causation

BACKGROUND

Pemoline is a central nervous system stimulant used in treating children with attention deficit-hyperactivity disorder. Hepatotoxicity has been commonly reported in association with pemoline; however, only two reports of cases of fatal liver failure have been published.

OBJECTIVES

We report on a 14-year-old boy who received concomitant pemoline and methylphenidate in whom fulminant liver failure occurred and for whom liver transplantation failed. Other causes of fulminant liver failure were ruled out, and the liver biopsy was suggestive of drug toxicity. We estimated the probability that these three cases represent an increased risk of fulminant liver failure associated with pemoline.

RESULTS

Based on the three known cases of fatal liver failure associated with pemoline use, we calculated that a child receiving pemoline has a relative risk of development of fulminant liver failure of 45.3 (95% confidence interval, 4.1 to 510). This highly significant association (p < 0.001) suggests causation.

CONCLUSIONS

Because pemoline has been widely used in recent years, further studies are needed to better quantify this risk in children with attention deficit-hyperactivity disorder.

Fulminant hepatic failure caused by tuberculosis

A 54 year old Asian woman developed fulminant hepatic failure followed by renal failure. Because of a past history of possible tuberculosis, she was given antituberculous drugs. The chest x ray was normal. A transjugular liver biopsy showed caseating necrosis, granulomas, and acid fast bacilli indicative of miliary tuberculosis. Despite full supportive therapy, her condition deteriorated and she died. Postmortem examination showed widespread miliary tuberculosis; culture confirmed the presence of Mycobacterium tuberculosis. Tuberculosis causes fulminant hepatic failure rarely and only three cases have been described. In this, as with the other cases, hyponatraemia and hepatomegaly were features at presentation. This is the first report of treatment being given before death.

The diagnosis and management of acute liver failure in dogs and cats

Management of the small animal patient with a presumptive diagnosis of acute liver failure should aim to provide high quality supportive care aimed at the functional derangements that occur. A definitive histopathologic diagnosis should be pursued to allow evaluation of the reversibility of the underlying condition. With the current advances in veterinary critical care, improved medical and technical management should reduce both morbidity and mortality in the patient with potentially reversible liver failure.

Fulminant hepatic failure: pathophysiology, treatment, and survival

Fulminant hepatic failure is characterized by severe metabolic derangements, neurologic complications and, ultimately, multiorgan failure. In the past three decades, improved intensive care has increased mean survival from 15% to 50% in certain patient groups by providing metabolic support and management of specific, frequent, and potentially fatal complications. However, outcome remains highly dependent on etiology. While intensive care is sufficient therapy in some patients (Group I), those with irreparable hepatic damage (Group III) can only survive if transplanted. In intermediate cases (Group II), the liver retains the potential to regenerate if the patient receives hepatic functional support. Major areas of current research in this field include development of hepatic support devices, strategies to accelerate and maximize hepatic regeneration, and criteria for accurate prognostic classification of patients.

Reye's and Reye-like syndromes, drug-related diseases? (causative agents, etiology, pathogenesis, and therapeutic approaches)

In the literature the separation between RS and RLS is confusing and makes it difficult to plan an appropriate preventive action or to develop new therapeutic approaches. We suggest that the generalized damage and encephalopathy seen in both RS and RLS may be due to a wide variety of causative agents that contribute to a common derangement, principally involving mitochondrial oxidative pathway. Fasting status and infections increase the catabolism and the subsequent flux of metabolites from peripheral tissues to the liver (FA and amino acids); cytokines (TNF, IL-1, and IL-6), in particular, mediate this effect during infection and experimental endotoxemia. Some drugs and other toxic compounds induce functional and morphological liver mitochondrial derangement. Oxidative metabolism is impaired, with subsequent stimulation of alternative pathways of oxidation, following production of unusual toxic acyl CoAs and dicarboxylic acids. Toxic compounds accumulate in the liver, deranging its functions and causing energy depletion, and are also released in the circulation from which they reach other tissues, including the brain. Neurons and astrocytes in the brain may be affected differently: Neurons suffer from the lack of energy and the effect of toxic compounds arriving from the bloodstream, and astrocytes may be directly affected by the beta-oxidation derangement. Very important may be genetic predisposition, which, by making the patient more sensitive to a particular causative agent, may facilitate the onset of RS and RLS. The therapeutic approach is, presently, mainly symptomatic, directed as it is to counteracting each alteration shown, depending by the clinical gravity. Other pharmacological approaches are only studied experimentally, like carnitine supplementation and PGE2 administration, or theoretically envisaged, like monoclonal antibody therapy directed at LPS or at pro-inflammatory cytokines or treatment with interferon-alpha.

Serial recording of sensory evoked potentials: a noninvasive prognostic indicator in fulminant liver failure

Sensory evoked potentials are markedly changed in patients with fulminant liver failure. It is unknown, however, whether serial recordings of sensory evoked potentials provide useful prognostic informations for patient management in fulminant liver failure. Ninety recordings of bilateral median nerve-stimulated short- and long-latency sensory evoked potentials were performed in 25 patients with fulminant liver failure (9 patients spontaneously recovered and survived, 8 patients were referred to emergency liver transplantation and 8 patients died). In all nine survivors the cortical long-latency sensory evoked potential N70 peak was constantly detectable between 74 and 162 ms. In all eight patients who subsequently underwent liver transplantation and in seven of eight patients who died, loss of the N70 peak developed during the course of fulminant liver failure. In 4 of 15 patients who were selected for liver transplantation according to the King's College criteria, the N70 peak was constantly detectable. All four transplantation candidates spontaneously recovered and survived without transplantation. In contrast, eight patients never did fulfill the criteria for liver transplantation. Five of them with constantly detectable N70 peak recovered spontaneously. However, in the remaining three patients loss of the N70 peak developed, and they ultimately died. The probability of correct outcome prediction by sensory evoked potentials is superior to that based on clinical criteria alone (0.96 vs. 0.72). Therefore serial recording of sensory evoked potentials may help identify (a) a subgroup among liver transplantation candidates who may spontaneously recover without transplantation and (b) a subgroup of patients with severe brain dysfunction who should undergo early liver transplantation even though they do not fulfill King's College criteria.

Seroepidemiological prevalence of hepatitis delta virus in eastern Saudi Arabia

To describe hypercholesterolemia in an urban community in Saudi Arabia, total serum cholesterol (TSC) was measured in 966 apparently healthy males (475 Saudi Arabs, 351 other Arabs and 140 non-Arabs) using a portable analyzer (Boehringer Model[R]). Mean age was 35.9 years (SD+/-9.1) and mean body mass index (BMI) was 26.2 kg/m(2) (SD+/-3.4) with a mean TSC of 5.20 mmol (SD+/-1.21). Mean TSC was significantly higher among non-Arabs at 5.74 mmol/L (SD+/-1.48) than in Saudi Arabs at 4.93 mmol/L (SD+/-1.11), P<0.001 mmol/L. TSC was higher than 5.20 mmol/L in 44.3% and higher than 6.80 mmol/L in 6.9% of the population. TSC was higher than 6.80 mmol/L in 3.6% of Saudi Arabs, 8.0% in other Arabs and 15.7% in the non-Arabs. This calls for cholesterol screening of the indigenous male population for hypercholesterolemia and other coronary heart disease risk factors at every opportunity. Among expatriate males, a mass screening strategy might be appropriate. The health care system needs appropriate adjustment to deal with this growing health problem.

Transcatheter hepatocyte transplantation: preclinical studies of anatomic consequences in the portal vascular bed

RATIONALE AND OBJECTIVES

Intrasplenic transplantation deposits hepatocytes in host hepatic sinusoids with amelioration of chronic liver failure and genetic deficiency states. Because portal resistance can be altered by intrasinusoidal transplanted cells, we examined whether hepatocyte recipients would develop deleterious portal hypertension or portosystemic collaterals.

METHODS

Syngeneic hepatocytes in suspension were transplanted into recipient rats by transcatheter injection into the splenic parenchyma. Subjects included recipients of 2 x 10(7) hepatocytes representing approximately 3% of the host hepatic mass, recipients of 7.5 x 10(7) hepatocytes representing approximately 12.5% of the host hepatic mass, normal control rats, and positive control rats with portal hypertension induced by partial portal vein constriction. Portal pressures were recorded with a sensitive transducer, portosystemic collaterals were demonstrated with direct splenoportography, and survival of transplanted cells was determined with an endogenous dipeptidyl peptidase IV reporter gene.

RESULTS

In normal rats, the portal pressure was 6.25 +/- 1.9 mm Hg with no portosystemic collaterals. By contrast, portal pressures were significantly increased in portal vein-constricted rats, 20.7 +/- 3.9 mm Hg (P < 0.001), with extensive portosystemic collaterals. In hepatocyte recipients, portal hypertension observed during transcatheter cell injection but proved transient. When animals were examined up to 16 weeks after hepatocyte transplantation, portal pressures were in the normal range (after 2 x 10(7) cells, 7.5 x 2.6 mm Hg; after 7.5 x 10(7) cells, 9.5 +/- 4.2 mm Hg, P = not significant). No portosystemic collaterals developed in hepatocyte recipients at various times up to 8 months after transplantation. Transplanted hepatocytes expressing the reporter gene were present in recipients with assimilation in host hepatic cords.

CONCLUSION

Despite injection of a massive number of cells, transcatheter hepatocyte transplantation was devoid of any significant portal vascular alterations or toxicity in recipients. These findings are consistent with assimilation of transplanted hepatocytes into host hepatic cords and will facilitate therapeutic applications in metabolic diseases or acute liver failure.

Acute liver failure

Acute liver failure is a multiorgan syndrome with dramatic clinical features and, often, a fatal outcome. It is characterized by the onset of coma and coagulopathy within 6 months, and usually in < 6 weeks, from onset of illness. Viral hepatitis, drug-related liver injury, and the alcohol-acetaminophen syndrome are the most common etiologies. Altered mental status accompanied by jaundice is a hallmark of acute liver failure. A unique feature is the evolution of increased intracranial pressure due to cerebral edema. The resulting cerebral ischemia and brainstem herniation account for approximately 50% of deaths in patients with acute liver failure. Mannitol therapy may successfully treat most patients with high intracerebral pressure. Most patients demonstrate features of the multiple organ failure syndrome, including a shock-like state, renal failure, and occasionally respiratory distress syndrome. Close monitoring of volume status is necessary, since administration of large quantities of fluid may be required. Infection is also common; most pathogens are gram-positive, and fungal infections are also seen. Because an optimum therapy for acute liver failure does not yet exist, liver transplantation should be considered early, before advanced levels of coma develop. Alternative, experimental treatment modalities include heterotopic liver grafting, administration of hepatocyte growth factor, use of an extracorporeal liver-assist device, and liver cell transplantation, but none of these has attained widespread use.