Predictive value of actin-free Gc-globulin in acute liver failure.

Serum concentrations of the actin scavenger Gc-globulin may provide prognostic information in acute liver failure (ALF). The fraction of Gc-globulin not bound to actin is postulated to represent a better marker than total Gc-globulin but has been difficult to measure. We tested a new rapid assay for actin-free Gc-globulin to determine its prognostic value when compared with the King's College Hospital (KCH) criteria in a large number of patients with ALF. A total of 252 patients with varying etiologies from the U.S. ALF Study Group registry were included; the first 178 patients constituted the learning set, and the last 74 patients served as the validation set. Actin-free Gc-globulin was determined with a commercial enzyme-linked immunosorbent assay kit. The median (range) actin-free Gc-globulin level at admission for the learning set was significantly reduced compared with controls (47 [0-183] mg/L vs. 204 [101-365] mg/L, respectively, P < 0.001). Gc-globulin levels were significantly higher in spontaneous survivors than in patients who died or were transplanted (53 [0-129] mg/L vs. 37 [0-183] mg/L, P = 0.002). A receiver operating characteristic curve analysis showed that a 40 mg/L cutoff level carried the best prognostic information, yielding positive and negative predictive values of 68% and 67%, respectively, in the validation set. The corresponding figures for the KCH criteria were 72% and 64%. A new enzyme-linked immunosorbent assay for actin-free Gc-globulin provides the same (but not optimal) prognostic information as KCH criteria in a single measurement at admission.

Biochemical and virologic parameters in patients co-infected with hepatitis C and HIV versus patients with hepatitis C mono-infection.

BACKGROUND: Previous studies of patients with hepatitis C virus (HCV) infection looking at the effect of human immunodeficiency virus (HIV) co-infection on biochemical parameters and HCV RNA level have shown conflicting results. Accurate characterization of the effect of HIV is important for evaluation and treatment of HCV in co-infected persons. METHODS: We studied 315 HCV mono-infected and 75 HCV-HIV co-infected subjects to determine the effect of HIV on biochemical parameters and HCV RNA and to determine the predictors of elevated serum alanine aminotransferase (ALT) levels and HCV RNA levels. RESULTS: The co-infected subjects were more likely to be African-American (55% vs 26%, P < 0.0005), have used injection drugs (68% vs 60%, P = 0.02), have detectable HCV RNA (84% vs 70.5%, P = 0.018), have HCV RNA levels >6 log10 IU/mL (60% vs 38%, P = 0.001), and have lower mean serum ALT levels (50.4 IU/mL vs 73.7 IU/mL, P = 0.006). In multivariable analyses, the following factors predicted an ALT level >50 IU/mL: log10 HCV RNA (OR, 1.15; 95% CI, 1.00 to 1.32); HIV co-infection (OR, 0.48; 95% CI, 0.25 to 0.89); and having ever been treated for HCV (OR, 1.92; 95% CI, 1.16 to 3.18). The only significant predictor of HCV RNA level >6 log10 IU/mL was HIV co-infection (OR, 2.75; 95% CI, 1.46 to 5.15). Significant predictors of having a detectable HCV RNA level were female sex (OR, 3.81; 95% CI, 1.18 to 12.25); HIV co-infection (2.45; 95% CI, 1.14 to 5.26); and ever being treated for HCV (OR, 1.96; 95% CI, 1.10 to 3.48). CONCLUSIONS: HCV-HIV co-infected persons have higher HCV RNA levels but lower serum ALT levels than HCV mono-infected patients. Criteria for performing liver biopsy and treating HCV infection in co-infected patients may need to be revisited.

Comorbid medical and psychiatric conditions and substance abuse in HCV infected persons on dialysis.

BACKGROUND/AIMS: The burden of comorbidity in the Hepatitis C virus (HCV) infected persons on dialysis is unknown. METHODS: We identified all HCV infected and uninfected subjects in the United States Renal Data System in the years 1997-1998 using ICD-9 codes. Controls were matched on the date of first dialysis. ICD-9 codes and claims data was used to identify medical and psychiatric comorbidities. RESULTS: We identified 5,737 HCV infected persons and 11,228 HCV uninfected subjects. HCV infected subjects were younger, more likely to be black race and male and more likely to have the following comorbidities: hypertension; hepatitis B; cirrhosis; wasting; anemia; human immunodeficiency virus (HIV) infection; major depression; mild depression; bipolar disorder; schizophrenia; post-traumatic stress disorder; drug use; alcohol use; smoking and less likely to have the following comorbidities: coronary artery disease; stroke; peripheral vascular disease; diabetes; cancer; erythropoietin use. After adjusting for age, gender and race, HCV infected subjects were more likely to have hypertension, hepatitis B, cirrhosis, wasting, anemia and HIV infection and less likely to have coronary artery disease and stroke. CONCLUSIONS: HCV infected persons on dialysis are more likely to have psychiatric comorbidities and substance abuse, as well as certain medical comorbidities. These factors should be considered when developing future intervention strategies.

Measurement of serum acetaminophen-protein adducts in patients with acute liver failure.

BACKGROUND & AIMS: Acetaminophen toxicity is the most common cause of acute liver failure (ALF) in the United States and Great Britain, but may be underrecognized in certain settings. Acetaminophen-protein adducts are specific biomarkers of drug-related toxicity in animal models and can be measured in tissue or blood samples. Measurement of serum adducts might improve diagnostic accuracy in acute liver failure (ALF) patients. METHODS: We measured serum acetaminophen-protein adducts using high-pressure liquid chromatography with electrochemical detection in coded sera of 66 patients with ALF collected prospectively at 24 US tertiary referral centers. Samples were included from 20 patients with well-characterized acetaminophen-related acute liver failure, 10 patients with ALF owing to other well-defined causes, 36 patients with ALF of indeterminate etiology, and 15 additional patients without ALF but with known acetaminophen overdose and minimal or no biochemical liver injury. RESULTS: Acetaminophen-protein adducts were detected in serum in 100% of known acetaminophen ALF patients and in none of the ALF patients with other defined causes, yielding a sensitivity and specificity of 100%. In daily serial samples, serum adducts decreased in parallel with aminotransferase levels. Seven of 36 (19%) indeterminate cases demonstrated adducts in serum suggesting that acetaminophen toxicity caused or contributed to ALF in these patients. Low adduct levels were present in 2 of 15 patients with acetaminophen overdose without significant liver injury. CONCLUSIONS: Measurement of serum acetaminophen-protein adducts reliably identified acetaminophen toxicity, and may be a useful diagnostic test for cases lacking historical data or other clinical information.

MELD and prediction of post-liver transplantation survival.

The model for end-stage liver disease (MELD) was developed to predict short-term mortality in patients with cirrhosis. It has since become the standard tool to prioritize patients for liver transplantation. We assessed the value of pretransplant MELD in the prediction of posttransplant survival. We identified adult patients who underwent liver transplantation at our institution during 1991-2002. Among 2,009 recipients, 1,472 met the inclusion criteria. Based on pretransplant MELD scores, recipients were stratified as low risk (< or = 15), medium risk (16-25), and high risk (>25). The primary endpoints were patient and graft survival. Mean posttransplant follow-up was 5.5 years. One-, 5- and 10-year patient survival was 83%, 72%, and 58%, respectively, and graft survival was 76%, 65%, and 53%, respectively. In univariable analysis, patient and donor age, patient sex, MELD score, disease etiology, and retransplantation were associated with posttransplantation patient and graft survival. In multivariable analysis adjusted for year of transplantation, patient age >65 years, donor age >50 years, male sex, and retransplantation and pretransplant MELD scores >25 were associated with poor patient and graft survival. The impact of MELD score >25 was maximal during the first year posttransplant. In conclusion, older patient and donor age, male sex of recipient, retransplantation, and high pretransplant MELD score are associated with poor posttransplant outcome. Pretransplant MELD scores correlate inversely with posttransplant survival. However, better prognostic models are needed that would provide an overall assessment of transplant benefit relative to the severity of hepatic dysfunction.

Acetaminophen-induced acute liver failure: results of a United States multicenter, prospective study.

Severe acetaminophen hepatotoxicity frequently leads to acute liver failure (ALF). We determined the incidence, risk factors, and outcomes of acetaminophen-induced ALF at 22 tertiary care centers in the United States. Detailed prospective data were gathered on 662 consecutive patients over a 6-year period fulfilling standard criteria for ALF (coagulopathy and encephalopathy), from which 275 (42%) were determined to result from acetaminophen liver injury. The annual percentage of acetaminophen-related ALF rose during the study from 28% in 1998 to 51% in 2003. Median dose ingested was 24 g (equivalent to 48 extra-strength tablets). Unintentional overdoses accounted for 131 (48%) cases, intentional (suicide attempts) 122 (44%), and 22 (8%) were of unknown intent. In the unintentional group, 38% took two or more acetaminophen preparations simultaneously, and 63% used narcotic-containing compounds. Eighty-one percent of unintentional patients reported taking acetaminophen and/or other analgesics for acute or chronic pain syndromes. Overall, 178 subjects (65%) survived, 74 (27%) died without transplantation, and 23 subjects (8%) underwent liver transplantation; 71% were alive at 3 weeks. Transplant-free survival rate and rate of liver transplantation were similar between intentional and unintentional groups. In conclusion, acetaminophen hepatotoxicity far exceeds other causes of acute liver failure in the United States. Susceptible patients have concomitant depression, chronic pain, alcohol or narcotic use, and/or take several preparations simultaneously. Education of patients, physicians, and pharmacies to limit high-risk use settings is recommended.

Complications and use of intracranial pressure monitoring in patients with acute liver failure and severe encephalopathy.

Monitoring of intracranial pressure (ICP) in acute liver failure (ALF) is controversial as a result of the reported complication risk (approximately 20%) and limited therapeutic options for intracranial hypertension. Using prospectively collected information from 332 patients with ALF and severe encephalopathy, we evaluated a recent experience with ICP monitoring in the 24 centers constituting the U.S. ALF Study Group. Special attention was given to the rate of complications, changes in management, and outcome after liver transplantation (LT). ICP monitoring was used in 92 patients (28% of the cohort), but the frequency of monitoring differed between centers (P < 0.001). ICP monitoring was strongly associated with the indication of LT (P < 0.001). A survey performed in a subset of 58 patients with ICP monitoring revealed intracranial hemorrhage in 10.3% of the cohort, half of the complications being incidental radiological findings. However, intracranial bleeding could have contributed to the demise of 2 patients. In subjects listed for LT, ICP monitoring was associated with a higher proportion of subjects receiving vasopressors and ICP-related medications. The 30-day survival post-LT was similar in both monitored and nonmonitored groups (85% vs. 85%). In conclusion, the risk of intracranial hemorrhage following ICP monitoring may have decreased in the last decade, but major complications are still present. In the absence of ICP monitoring, however, patients listed for LT appear to be treated less aggressively for intracranial hypertension. In view of the high 30-day survival rate after LT, future studies of the impact of intracranial hypertension should also focus on long-term neurological recovery from ALF.

Gc-globulin and prognosis in acute liver failure.

Serum concentrations of the actin scavenger Gc-globulin are reduced in acute liver failure (ALF). Prospectively, we tested Gc-globulin's value to predict outcome following ALF using sera from 182 patients with ALF from the U.S. ALF Study Group. Admission serum levels of Gc-globulin (normal range: 350-500 mg/L) were studied by an immunonephelometric method. The median (range) serum Gc-globulin level on admission for the entire group was 91 (5-307) mg/L. Gc-globulin levels were significantly higher in spontaneous survivors than in patients who died or underwent transplantation (113 [5-301] mg/L vs. 73 [5-307] mg/L, P < 0.001). Those surviving non-acetaminophen (paracetamol)-induced ALF without transplantation had higher Gc-globulin levels than nonsurvivors (102 [5-301] mg/L vs. 61 [5-232] mg/L, P = 0.002), whereas there was no significant difference in levels between the groups in patients with acetaminophen-induced ALF. A cutoff level of 80 mg/L in the non-acetaminophen group yielded positive and negative predictive values of 85% and 43%, respectively. The corresponding figures for the King's College criteria were 90% and 49%, respectively. In conclusion, we found that Gc-globulin levels were markedly decreased in patients with ALF; the lowest levels were observed in patients who died or were transplanted. In contrast to previous studies, this study demonstrated that Gc-globulin has prognostic value in patients with non-acetaminophen-induced ALF, in the same range as the King's College criteria. Further refinements of the assay would be necessary to make it more accurate and of practical utility.

Acute liver failure due to amoxicillin and amoxicillin/clavulanate.

The aim of our study is to report upon the presentation of two patients with life-threatening acute liver failure (ALF) due to amoxicillin and amoxicillin/clavulanate. A 59-year-old, Caucasian male presented with ALF 34 days after receiving amoxicillin/clavulanate. Despite aggressive supportive care, he died on hospital day 10. A 42-year-old, Caucasian female presented with ALF 21 days after receiving amoxicillin. She underwent successful liver transplantation on hospital day 19. In both cases, all competing causes of ALF had been excluded, liver pathology was consistent with drug-induced hepatitis, and cases were deemed "definite/highly probable" using causality assessment. Amongst 14 prior ALF/death cases due to amoxicillin/clavulanate, the mean age (62 years), male predominance (57%), and mean delay from drug cessation to presentation (17 days) is similar to what has been reported in patients with self-limited cholestatic hepatitis. Acute liver failure is a rare manifestation of amoxicillin and amoxicillin/clavulanate hepatotoxicity with no obvious clinical features at presentation portending a poor prognosis. Early transfer of patients with severe drug-induced hepatotoxicity (i.e., encephalopathy or coagulopathy) to a transplant center is recommended due to their poor likelihood of recovery.

Fulminant hepatic failure.

FHF is a devastating illness of varied causes, carrying considerable mortality and affecting patients with previously healthy livers. The clinical presentation varies widely but encephalopathy is the defining criterion. Management requires a multidisciplinary approach, including rapid triage, monitoring, and referral to a transplantation center for further evaluation. Early prognostication and timely availability of donor livers are essential for a successful outcome. A donor shortage, however, continues to pose problems for both hepatologists and surgeons. Effective liver support devices may greatly prolong the window of opportunity to provide a donor liver, or alternatively to allow the native liver to regenerate. Despite decades of great progress in the field of liver support systems, the ideal system is still a long-cherished goal in hepatology. Hybrid systems have garnered most of the recent attention, but the quest for improved synthetic function has not yet been realized. It is hoped that rapid conceptual and technologic developments with respect to hybrid systems, hepatocyte transplantation, and xenografting will yield a safe and accessible tool for managing these critically ill patients. Controlled, multicenter trials in well-defined patient groups and with standard outcome measures are essential to evaluate the clinical value of these devices. A better understanding of mechanisms responsible for liver cell death and multiorgan failure, and the development of strategies to enhance liver regeneration, may allow a more targeted approach to therapy.

Viral hepatitis-related acute liver failure.

OBJECTIVES: Viral hepatitis has previously been the major cause of acute liver failure (ALF) in the United States. We aimed to determine the incidence of viral hepatitis-related ALF and to compare the outcome and clinical and biochemical variables in patients with hepatitis A and B. METHODS: A total of 354 patients with ALF from multiple centers were screened for possible acute viral etiology. RESULTS: Forty-three patients (12.1% of all ALF cases) had acute viral hepatitis: hepatitis A (n = 16), hepatitis B (n = 26), and herpes simplex virus infection (n = 1). There was no difference between groups with regard to age, gender, body mass index, admission or peak coma grade, symptom duration, admission mean arterial pressure, temperature, or biochemical liver tests, creatinine, arterial pH, or rate of infections. Platelet count was significantly higher in hepatitis A patients than in hepatitis B patients. The transplantation-free (spontaneous) survival rate was significantly higher for hepatitis A patients (69%) than for hepatitis B patients (19%, p = 0.007), whereas the liver transplantation rate was higher in hepatitis B patients (62%) than in hepatitis A patients (19%, p = 0.017). Spontaneous survivors had significantly higher mean arterial pressure, higher platelet count, and lower AST/ALT ratio than patients who did not survive spontaneously. CONCLUSIONS: Viral hepatitis now comprises only one-eighth of all ALF cases in the United States. The marked difference in spontaneous survival between hepatitis A and B cannot be explained by the severity of hepatic dysfunction on admission but may rather be an inherent feature of the infections or a bias toward transplanting patients with hepatitis B.

Results of a prospective study of acute liver failure at 17 tertiary care centers in the United States.

BACKGROUND: Because acute liver failure is rare, related data have been sparse. Studies have suggested that viral hepatitis is the most common underlying cause of this condition. OBJECTIVE: To describe the clinical features, presumed causes, and short-term outcomes of acute liver failure. DESIGN: Prospective cohort study. SETTING: 17 tertiary care centers participating in the U.S. Acute Liver Failure Study Group. PATIENTS: 308 consecutive patients with acute liver failure, admitted over a 41-month period. MEASUREMENTS: Detailed clinical and laboratory data collected during hospitalization, including outcome 3 weeks after study admission. RESULTS: 73% of patients were women; median age was 38 years. Acetaminophen overdose was the most common apparent cause of acute liver failure, accounting for 39% of cases. Idiosyncratic drug reactions were the presumptive cause in 13% of cases, viral hepatitis A and B combined were implicated in 12% of cases, and 17% of cases were of indeterminate cause. Overall patient survival at 3 weeks was 67%. Twenty-nine percent of patients had liver transplantation, and 43% survived without transplantation. Short-term transplant-free survival varied greatly, from 68% for patients with acetaminophen-related liver failure to 25% and 17% for those with other drug reactions and liver failure of indeterminate cause, respectively. Coma grade at admission appeared to be associated with outcome, but age and symptom duration did not. CONCLUSIONS: Acetaminophen overdose and idiosyncratic drug reactions have replaced viral hepatitis as the most frequent apparent causes of acute liver failure. Apparent cause and coma grade at admission were associated with outcome. Although transplantation may improve patient survival, it was unavailable or unnecessary for most patients.

Ribavirin dose modification based on renal function is necessary to reduce hemolysis in liver transplant patients with hepatitis C virus infection.

Hepatitis C virus (HCV) is currently the most common etiology for liver transplantation (LTx) in the United States. A significant number of patients develop recurrent HCV after LTx. Although there is no completely satisfactory treatment for recurrent HCV, a combination of interferon-alpha (INF) and ribavirin remains the most widely used. Ribavirin is eliminated through the kidneys and tends to accumulate in the presence of renal dysfunction. The primary side effect of ribavirin is hemolysis. The goal of the present study was to correlate the incidence of hemolysis with renal function in LTx patients with recurrent HCV who were being treated with ribavirin. The incidence of hemolysis and the renal function were examined in 72 liver transplant patients (58 male and 14 female patients) with recurrent HCV receiving INF (3 million units, three times per week) and ribavirin (initial dose of 400 mg twice daily). Patients were grouped according to the decrease in the percentage of hematocrit after the introduction of ribavirin, with their baseline serum creatinine and creatinine clearance calculated using the Cockcroft-Gault formula. The decrease in the percentage of hematocrit after ribavirin treatment was also examined with respect to creatinine clearance as a continuous variable. In addition, for purposes of presentation, patients were analyzed in three groups: creatinine clearance of >/= 70 mL/min (group A), creatinine clearance < 70 mL/min and >/= 40 mL/min (group B), and creatinine clearance < 40 mL/min (group C). Forty-five (62.5%) patients experienced a decrease in hematocrit (Hct) >/=15% after starting INF and ribavirin. The mean serum creatinine was 1.3 +/- 0.5 mg/dL (median, 1.3) in this group, and the mean calculated creatinine clearance was 71 +/- 29 mL/min (median, 66.47). In the 27 patients who did not show a significant decrease (< 15%) in hematocrit, the mean serum creatinine was 1.1 +/- 0.3 mg/dL (median, 1.0) and the mean creatinine clearance was 95 +/- 39 (median, 96) mL/min (P =.018). On continuous variable of calculated creatinine clearance, there was a trend in the decrease in hematocrit after ribavirin treatment compared with pretreatment (P =.09). However, the rate of hemolysis was significantly different in group A (53.7%), group B (70.8%), and group C (100%) (P =.042). Patients on INF and ribavirin therapy who experienced hemolysis had significantly higher serum creatinine levels and lower creatinine clearances compared with those who did not have hemolysis. The incidence of hemolysis was significantly associated with higher serum creatinine and decreased creatinine clearance. Because ribavirin is eliminated by the kidneys, this observation points to the need for adjustments in the dose of this agent in LTx patients, who tend to have some degree of renal dysfunction, to reduce the incidence of hemolysis. Further pharmacokinetic studies of ribavirin in LTx patients with varying degrees of renal function may allow the development of an algorithm for the safer use of ribavirin in HCV-positive LTx patients.

A pilot study of interferon alfa and ribavirin combination in liver transplant recipients with recurrent hepatitis C.

Although interferon alfa (IFN-alpha) and ribavirin are widely used in the treatment of hepatitis C, their role in the transplant recipient is unclear. We conducted a pilot study to determine the efficacy and safety of this therapy in transplant recipients with recurrent hepatitis C. Patients at least 6 months posttransplantation were treated with IFN-alpha 3 million units 3 times a week subcutaneously and ribavirin 800 mg daily by mouth for 48 weeks followed by ribavirin monotherapy for 24 weeks. The primary end point was sustained virologic response, and secondary end points included biochemical, virologic, and histologic responses at the end of combination treatment. Thirty-eight patients initiated therapy but 16 withdrew due to adverse effects, including 2 with myocardial infarction. Median age was 50 years; 74% were men, and 91% had genotype 1. The median interval between transplantation and enrollment was 23 months. On an intention-to-treat basis, 7 patients (18%) had a biochemical and 5 (13%) had a virologic response at the end of combination treatment. Inflammatory activity did not change, but fibrosis worsened in virologic nonresponders. Ribavirin maintenance caused a further decrease in serum alanine aminotransferase levels, but hepatitis C virus (HCV) RNA levels increased. Only 2 of the 38 patients (5%) had a sustained virologic response. Several patients required treatment with erythropoietin for anemia. In conclusion, IFN-alpha and ribavirin are effective in a small proportion of liver allograft recipients with recurrent hepatitis C. Adverse effects occur commonly, requiring dose reductions and treatment withdrawal.