Ezmina Lalani

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. (HEPATOLOGY 2005;42:1364–1372.)

Screening for Wilson Disease in Acute Liver Failure: A Comparison of Currently Available Diagnostic Tests

Acute liver failure (ALF) due to Wilson disease (WD) is invariably fatal without emergency liver transplantation. Therefore, rapid diagnosis of WD should aid prompt transplant listing. To identify the best method for diagnosis of ALF due to WD (ALF‐WD), data and serum were collected from 140 ALF patients (16 with WD), 29 with other chronic liver diseases and 17 with treated chronic WD. Ceruloplasmin (Cp) was measured by both oxidase activity and nephelometry and serum copper levels by atomic absorption spectroscopy. In patients with ALF, a serum Cp <20 mg/dL by the oxidase method provided a diagnostic sensitivity of 21% and specificity of 84% while, by nephelometry, a sensitivity of 56% and specificity of 63%. Serum copper levels exceeded 200 μg/dL in all ALF‐WD patients measured (13/16), but were also elevated in non‐WD ALF. An alkaline phosphatase (AP) to total bilirubin (TB) ratio <4 yielded a sensitivity of 94%, specificity of 96%, and a likelihood ratio of 23 for diagnosing fulminant WD. In addition, an AST:ALT ratio >2.2 yielded a sensitivity of 94%, a specificity of 86%, and a likelihood ratio of 7 for diagnosing fulminant WD. Combining the tests provided a diagnostic sensitivity and specificity of 100%. Conclusion: Conventional WD testing utilizing serum ceruloplasmin and/or serum copper levels are less sensitive and specific in identifying patients with ALF‐WD than other available tests. More readily available laboratory tests including alkaline phosphatase, bilirubin and serum aminotransferases by contrast provides the most rapid and accurate method for diagnosis of ALF due to WD. (HEPATOLOGY 2008.)

Steroid use in acute liver failure

Drug‐induced and indeterminate acute liver failure (ALF) might be due to an autoimmune‐like hepatitis that is responsive to corticosteroid therapy. The aim of this study was to evaluate whether corticosteroids improve survival in fulminant autoimmune hepatitis, drug‐induced, or indeterminate ALF, and whether this benefit varies according to the severity of illness. We conducted a retrospective analysis of autoimmune, indeterminate, and drug‐induced ALF patients in the Acute Liver Failure Study Group from 1998‐2007. The primary endpoints were overall and spontaneous survival (SS, survival without transplant). In all, 361 ALF patients were studied, 66 with autoimmune (25 steroids, 41 no steroids), 164 with indeterminate (21 steroids, 143 no steroids), and 131 with drug‐induced (16 steroids, 115 no steroids) ALF. Steroid use was not associated with improved overall survival (61% versus 66%, P = 0.41), nor with improved survival in any diagnosis category. Steroid use was associated with diminished survival in certain subgroups of patients, including those with the highest quartile of the Model for Endstage Liver Disease (MELD) (>40, survival 30% versus 57%, P = 0.03). In multivariate analysis controlling for steroid use and diagnosis, age (odds ratio [OR] 1.37 per decade), coma grade (OR 2.02 grade 2, 2.65 grade 3, 5.29 grade 4), MELD (OR 1.07), and pH < 7.4 (OR 3.09) were significantly associated with mortality. Although steroid use was associated with a marginal benefit in SS overall (35% versus 23%, P = 0.047), this benefit did not persistent in multivariate analysis; mechanical ventilation (OR 0.24), MELD (OR 0.93), and alanine aminotransferase (1.02) were the only significant predictors of SS. Conclusion: Corticosteroids did not improve overall survival or SS in drug‐induced, indeterminate, or autoimmune ALF and were associated with lower survival in patients with the highest MELD scores. (Hepatology 2014;59:612–621)

Detection of anti‐isoniazid and anti–cytochrome P450 antibodies in patients with isoniazid‐induced liver failure

Isoniazid (INH)‐induced hepatotoxicity remains one of the most common causes of drug‐induced idiosyncratic liver injury and liver failure. This form of liver injury is not believed to be immune‐mediated because it is not usually associated with fever or rash, does not recur more rapidly on rechallenge, and previous studies have failed to identify anti‐INH antibodies (Abs). In this study, we found Abs present in sera of 15 of 19 cases of INH‐induced liver failure. Anti‐INH Abs were present in 8 sera; 11 had anti–cytochrome P450 (CYP)2E1 Abs, 14 had Abs against CYP2E1 modified by INH, 14 had anti‐CYP3A4 antibodies, and 10 had anti‐CYP2C9 Abs. INH was found to form covalent adducts with CYP2E1, CYP3A4, and CYP2C9. None of these Abs were detected in sera from INH‐treated controls without significant liver injury. The presence of a range of antidrug and autoAbs has been observed in other drug‐induced liver injury that is presumed to be immune mediated. Conclusion: These data provide strong evidence that INH induces an immune response that causes INH‐induced liver injury. (Hepatology 2014;59:1084–1093)

Elevated troponin I levels in acute liver failure: Is myocardial injury an integral part of acute liver failure?

Although rare instances of cardiac injury or arrhythmias have been reported in acute liver failure (ALF), overall, the heart is considered to be spared in this condition. Troponin I, a sensitive and specific marker of myocardial injury, may be elevated in patients with sepsis and acute stroke without underlying acute coronary syndrome, indicating unrecognized cardiac injury in these settings. We sought to determine whether subclinical cardiac injury might also occur in acute liver failure. Serum troponin I levels were measured in 187 patients enrolled in the US Acute Liver Failure Study Group registry, and correlated with clinical variables and outcomes. Diagnoses were representative of the larger group of >1000 patients thus far enrolled and included 80 with acetaminophen‐related injury, 26 with viral hepatitis, 19 with ischemic injury, and 62 others. Overall, 74% of patients had elevated troponin I levels (>0.1 ng/ml). Patients with elevated troponin I levels were more likely to have advanced hepatic coma (grades III or IV) or to die (for troponin I levels >0.1 ng/ml, odds ratio 3.88 and 4.69 for advanced coma or death, respectively). Conclusion: In acute liver failure, subclinical myocardial injury appears to occur more commonly than has been recognized, and its pathogenesis in the context of acute liver failure is unclear. Elevated troponin levels are associated with a significant increase in morbidity and mortality. Measurement of troponin I levels may be helpful in patients with acute liver failure, to detect unrecognized myocardial damage and as a marker of unfavorable outcome. (HEPATOLOGY 2007;45:1489–1495.)

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 Kings 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. Liver Transpl 13:1324–1329, 2007.

The role of etiology in the hyperamylasemia of acute liver failure.

OBJECTIVES:Hyperamylasemia (HA) is often reported in patients with acute liver failure (ALF). Direct toxic effects of acetaminophen on the pancreas have been postulated, but the occurrence of HA in other etiologies raises the question of whether multiorgan failure is part of the pathogenesis of HA in this setting. Our main aim was to describe and analyze the incidence, clinical characteristics, and outcomes of HA in ALF of different etiologies.METHODS:Patients enrolled in the Acute Liver Failure Study Group registry with an admission amylase value available were included. For the purpose of this analysis, HA was defined as ≥3× upper limits of normal. Patients were classified as having acetaminophen (APAP)- or non-APAP-induced ALF, and by amylase group: normal (<115), mildly elevated (115–345), or HA (>345). Significant variables identified by univariate analysis were added to a multiple linear regression model. The primary outcome was overall survival.RESULTS:In total, 622 eligible patients were identified in the database, including 287 (46%) with APAP-induced ALF; 76 (12%) patients met the criteria for HA. Among patients with HA, 7 (9%) had documented clinical pancreatitis. The incidence of HA was similar among APAP (13%) and non-APAP (12%) patients. Although HA was associated with renal failure and greater Model for End-stage Liver Disease scores for both groups, HA was not an independent predictor of mortality in multivariate analysis.CONCLUSIONS:Although not an independent predictor of mortality, HA in ALF was present in all etiologies and was associated with diminished overall survival. HA appeared to be related to renal dysfunction in both groups and multiorgan failure in non-APAP ALF.

Association Between Plasma Level of Galectin-9 and Survival of Patients With Drug-Induced Acute Liver Failure.

BACKGROUND & AIMS Fewer than 50% of patients with acute liver failure (ALF) recover spontaneously, and ALF has high mortality without liver transplantation. Kupffer cells have been reported to mediate liver inflammation during drug-induced injury. Galectin-9 is produced by Kupffer cells and has diverse roles in regulating immunity. We investigated whether plasma levels of galectin-9 are associated with outcomes of patients with ALF. METHODS We analyzed plasma samples (collected at time of hospital admission) and clinical data from 149 patients included in the Acute Liver Failure Study Group from July 2006 through November 2010 (110 had acetaminophen-induced hepatotoxicity and 39 had nonacetaminophen drug-induced liver injury). We compared data with those from all patients enrolled in the study (from July 1, 2006 through October 30, 2013), and from healthy individuals of similar ages with no evidence of liver disease (control subjects). Plasma levels of galectin-9 were measured using a polyclonal antibody and colorimetric assay. RESULTS Patients with ALF had statistically higher plasma levels of galectin-9 than control subjects, but levels did not differ significantly between patients with acetaminophen-induced liver injury and drug-induced liver injury. A level of galectin-9 above 690 pg/mL was associated with a statistically significant increase in risk for mortality or liver transplantation caused by ALF. Competing risk analyses associated level of galectin-9 with transplant-free survival, independently of Model For End-Stage Liver Disease score or systemic inflammatory response syndrome. CONCLUSIONS A one-time measurement of plasma galectin-9 level can be used to assign patients with ALF to high-, intermediate-, and low-risk groups. The combination of galectin-9 level and Model For End-Stage Liver Disease score was more closely associated with patient outcome than either value alone. These data might be used to determine patient prognoses and prioritize patients for liver transplantation. ClinicalTrials.gov ID NCT00518440.