Standardization of nomenclature and causality assessment in drug-induced liver injury: summary of a clinical research workshop

Sepsis-associated liver injury: Incidence, classification and the clinical significance

AIM

  Although it is a common complication of sepsis, sepsis-associated liver injury has not been substantially recognized, because its diagnostic criteria and clinical implications are unclear. We aimed to elucidate the incidence, manifestation, disease type classification and prognosis of sepsis-associated liver injury.

METHODS

  The subjects were 588 patients admitted to our hospital for sepsis between 2001 and 2010. They were classified into "normal liver function", "sepsis-associated liver injury" and "sepsis-not-associated liver injury" groups. Sepsis-associated liver injury was classified as either "cholestatic", "hepatocellular" or "shock liver." Each of these three subgroups was further classified into "with jaundice" or "without jaundice". The primary end-point was the "poor prognosis ratio", defined as the proportion of patients whose prognosis was "unchanged", "worsened" or "died".

RESULTS

  Among the 449 subjects except for sepsis-not-associated liver injury (n = 139), the incidence of sepsis-associated liver injury was 34.7% (156/449), including 75 cholestatic (48.1%), 34 hepatocellular (21.8%) and 47 shock liver (30.1%) cases. Jaundice was a complication in 25 (33%), six (17.6%) and four (8.5%) patients in each group, respectively. The poor prognosis ratio was higher in males (37.5%) and in the elderly (47.7%); it was 48.0%, 38.2% and 62.8% in the cholestatic, hepatocellular and shock liver groups, respectively, and higher than the normal liver function (18.4%) group (P < 0.0001). It was also higher in patients with jaundice (68.6%) than in those without (45.5%) (P < 0.0001).

CONCLUSION

  Sepsis-associated liver injury, especially with jaundice, is a significant predictive sign of poor prognosis in patients with sepsis.

Amoxicillin-clavulanic acid hepatotoxicity in children

OBJECTIVES

The objectives of the present study were to determine the importance of amoxicillin-clavulanic acid (AC) hepatotoxicity in the paediatric population and to characterise the episodes identified and potential host-specific factors. This was addressed via a prospective observational study in which 8 Spanish hospitals participated.

METHODS

A total of 11 cases were examined. For each patient included in the study, a structured and codified data-collection protocol was complied with, taking note of patient demographics, characteristics of the treatment assumed to provoke the reaction, concomitant medication, course and outcome of the episode, and laboratory variables during the reaction. The latter were determined every 6 months from the outset to the eventual resolution of the case.

RESULTS

A total of 11 cases of AC hepatotoxicity were detected, affecting 9 boys and 2 girls, ages 1 to 11 years. Causality criteria were assessed using the Council for International Organizations of Medical Sciences scale.

CONCLUSIONS

We conclude that the introduction of hepatotoxicity record systems in paediatric care, together with the continuing study and development of existing systems, would contribute to improving our epidemiological knowledge about the harmful effects of drugs on the liver.

Drug-induced liver injury in hospitalized patients with notably elevated alanine aminotransferase

AIM: To identify the proportion, causes and the nature of drug-induced liver injury (DILI) in patients with notably elevated alanine aminotransferase (ALT).

METHODS: All the inpatients with ALT levels above 10 times upper limit of normal range (ULN) were retrospectively identified from a computerized clinical laboratory database at our hospital covering a 12-mo period. Relevant clinical information was obtained from medical records. Alternative causes of ALT elevations were examined for each patient, including biliary abnormality, viral hepatitis, hemodynamic injury, malignancy, DILI or undetermined and other causes. All suspected DILI cases were causality assessed using the Council for International Organizations of Medical Sciences scale, and only the cases classified as highly probable, probable, or possible were diagnosed as DILI. Comments related to the diagnosis of DILI in the medical record and in the discharge letter for each case were also examined to evaluate DILI detection by the treating doctors.

RESULTS: A total of 129 cases with ALT > 10 ULN were identified. Hemodynamic injury (n = 46, 35.7%), DILI (n = 25, 19.4%) and malignancy (n = 21, 16.3%) were the top three causes of liver injury. Peak ALT values were lower in DILI patients than in patients with hemodynamic injury (14.5 ± 5.6 ULN vs 32.5 ± 30.7 ULN, P = 0.001). Among DILI patients, one (4%) case was classified as definite, 19 (76%) cases were classified as probable and 5 (20%) as possible according to the CIOMS scale. A hepatocellular pattern was observed in 23 (92%) cases and mixed in 2 (8%). The extent of severity of liver injury was mild in 21 (84%) patients and moderate in 4 (16%). Before discharge, 10 (40%) patients were recovered and the other 15 (60%) were improved. The improved patients tended to have a higher peak ALT (808 ± 348 U/L vs 623 ± 118 U/L, P = 0.016) and shorter treatment duration before discharge (8 ± 6 d vs 28 ± 12 d, P = 0.008) compared with the recovered patients. Twenty-two drugs and 6 herbs were found associated with DILI. Antibacterials were the most common agents causing DILI in 8 (32%) cases, followed by glucocorticoids in 6 (24%) cases. Twenty-four (96%) cases received treatment of DILI with at least one adjunctive drug. Agents for treatment of DILI included anti-inflammatory drugs (e.g., glycyrrhizinate), antioxidants (e.g., glutathione, ademetionine 1,4-butanedisulfonate and tiopronin), polyene phosphatidyl choline and herbal extracts (e.g., protoporphyrin disodium and silymarin). Diagnosis of DILI was not mentioned in the discharge letter in 60% of the cases. Relative to prevalent cases and cases from wards of internal medicine, incident cases and cases from surgical wards had a higher risk of missed diagnosis in discharge letter [odds ratio (OR) 32.7, 95%CI (2.8-374.1), and OR 58.5, 95%CI (4.6-746.6), respectively].

CONCLUSION: DILI is mostly caused by use of antibacterials and glucocorticoids, and constitutes about one fifth of hospitalized patients with ALT > 10 ULN. DILI is underdiagnosed frequently.

Upper limits of normal for serum alanine aminotransferase levels in Chinese Han population

BACKGROUND AND OBJECTIVES

Serum alanine aminotransferase (ALT) activity is the most common tool for the assessment of liver diseases. However, it is not clear whether the current normal ALT range really discriminate patients with or without liver diseases. The present study was to establish a new normal range of ALT and examine its ability to identify patients with hepatitis B or nonalcoholic fatty liver disease (NAFLD) in Chinese Han population.

METHODS

53037 adults were included in this study from January 1st 2008 to August 31st 2010. The 95th percentile of ALT in population with relative low risk factors for liver diseases was set as the new upper limits of normal ALT in gender-specific manner.

RESULTS

The 95(th) percentile levels at low risk factors for liver diseases were achieved at 35 U/L for men and 23 U/L for women. The concordance statistics for detection were 0.873 (95%CI: 0.865-0.881) for HBV and 0.932 (95%CI: 0.927-0.937) for NAFLD in men while 0.857 (95%CI: 0.850-0.864) for HBV and 0.909 (95%CI: 0.903-0.915) for NAFLD in women. The median sensitivity of the current used ALT upper limit (40 U/L) was 6.6% for HBV and 29.7% for NAFLD and median specificity was 98.7% for men and 99.4% for women. Using our new-derived thresholds, the sensitivities ranged from 35.3% to 61.1% and the specificities were 94.8% for men and 94.6% for women.

CONCLUSIONS

Our results suggest that upper limits of ALT 35 U/L for men and 23 U/L for women in Chinese Han population. Re-consideration of normal limits of ALT should be recommended.

TRIAL REGISTRATION

ChiCTR.org ChiCTR-OCS-11001173.

An Update on Drug-induced Liver Injury

Idiosyncratic drug-induced liver injury (DILI) is an important cause of morbidity and mortality following drugs taken in therapeutic doses. Hepatotoxicity is a leading cause of attrition in drug development, or withdrawal or restricted use after marketing. No age is exempt although adults and the elderly are at increased risk. DILI spans the entire spectrum ranging from asymptomatic elevation in transaminases to severe disease such as acute hepatitis leading to acute liver failure. The liver specific Roussel Uclaf Causality Assessment Method is the most validated and extensively used for determining the likelihood that an implicated drug caused DILI. Asymptomatic elevation in liver tests must be differentiated from adaptation. Drugs producing DILI have a signature pattern although no single pattern is characteristic. Antimicrobial and central nervous system agents including antiepileptic drugs are the leading causes of DILI worldwide. In the absence of a diagnostic test or a biomarker, the diagnosis rests on the evidence of absence of competing causes such as acute viral hepatitis, autoimmune hepatitis and others. Recent studies show that antituberculosis drugs given for active or latent disease are still a major cause of drug-induced liver injury in India and the West respectively. Presence of jaundice signifies a severe disease and entails a worse outcome. The pathogenesis is unclear and is due to a mix of host, drug metabolite and environmental factors. Research has evolved from incriminating candidate genes to genome wide analysis studies. Immediate cessation of the drug is key to prevent or minimize progressive damage. Treatment is largely supportive. N-acetylcysteine is the antidote for paracetamol toxicity. Carnitine has been tried in valproate injury whereas steroids and ursodeoxycholic acid may be used in DILI associated with hypersensitivity or cholestatic features respectively. This article provides an overview of the epidemiology, the patterns of hepatotoxicity, the pathogenesis and associated risk factors besides its clinical management.

Frequency, clinical presentation, and outcomes of drug-induced liver injury after liver transplantation

Drug-induced liver injury (DILI) is increasingly being recognized as a common cause of acute hepatitis. The clinical impact of DILI after liver transplantation (LT) is not known. The aim of this study was to describe the frequency, clinical presentation, and outcomes of DILI in LT recipients. LT recipients with possible DILI were identified with electronic pathology records and clinical note database retrieval tools. Diagnostic criteria were applied to identify cases of DILI. Twenty-nine of 1689 LT recipients (1.7%) were identified with DILI. The mean age was 52 years, and 52% were women. The major indications for LT were primary sclerosing cholangitis (28%), cholangiocarcinoma (14%), and hepatocellular carcinoma (14%). The severity of DILI was mild or moderate in 92% of the cases. Nausea or diarrhea (31%), jaundice (24%), and pruritus (10%) were the most common symptoms at the time of diagnosis. The mean biochemistry values were as follows: alanine aminotransferase, 204 ± 263 U/L; aspartate aminotransferase, 108 ± 237 U/L; alkaline phosphatase, 469 ± 689 U/L; and total bilirubin, 1.9 ± 10.3 mg/dL. The median duration of medication use until the diagnosis of DILI was 57 days, and the major agent classes were antibiotics (48%), immunosuppressive agents (14%), and antihyperlipidemic drugs (7%). Trimethoprim-sulfamethoxazole was the most common implicated agent (n = 11). Serum liver enzymes improved within a median time of 34 days (range = 5-246 days) after drug withdrawal. Hepatic retransplantation or death did not occur. Among the 50 cases with possible DILI explained by other causes, 13 individuals (26%) had no alternative diagnosis despite histological findings compatible with DILI. In conclusion, DILI is a rare yet underrecognized event among LT recipients. The majority of cases are not clinically severe, and they resolve after drug cessation without hepatic retransplantation or death.

The clinical features of drug-induced liver injury observed through liver biopsy: focus on relevancy to autoimmune hepatitis

Background/Aims

Accurate diagnosis of drug-induced liver injury (DILI) is difficult without considering the possibility of underlying diseases, especially autoimmune hepatitis (AIH). We investigated the clinical patterns in patients with a history of medication, liver-function abnormalities, and in whom liver biopsy was conducted, focusing on accompaniment by AIH.

Methods

The clinical, serologic, and histologic findings of 29 patients were compared and analyzed. The patients were aged 46.2±12.8 years (mean±SD), and 72.4% of patient were female. The most common symptom and causal drug were jaundice (58.6%) and herbal medications (55.2%), respectively.

Results

Aspartate aminotransferase (AST), alanine aminotransferase, total bilirubin, alkaline phosphatase, and γ-glutamyl transpeptidase levels were 662.2±574.8 U/L, 905.4±794.9 U/L, 12.9±10.8 mg/dL, 195.8±123.3 U/L, and 255.3±280.8 U/L, respectively. According to serologic and histologic findings, 21 cases were diagnosed with DILI and 8 with AIH. The AIH group exhibited significantly higher AST levels (537.1±519.1 vs. 1043.3±600.5 U/L), globulin levels (2.7±0.4 vs. 3.3±0.5 g/dL), and prothrombin time (12.9±2.4 vs. 15.2±3.9 s; P<0.05). Antinuclear antibody was positive in 7 of 21 cases of DILI and all 8 cases of AIH (P=0.002). The simplified AIH score was 3.7±0.9 in the DILI group and 6.5±0.9 in the AIH group (P<0.001).

Conclusions

Accurate diagnosis is necessary for patients with a history of medication and visits for liver-function abnormalities; in particular, the possibility of AIH should be considered.

TNF-α genetic polymorphism -308G/A and antituberculosis drug-induced hepatitis

BACKGROUND

While the mechanisms underlying the development of drug-induced liver injury are not clear, there is evidence to suggest that tumor necrosis factor-α (TNF-α) plays an important role in drug- or drug metabolite-induced immune responses. We hypothesized that polymorphisms in the TNF-α gene are associated with anti-tuberculosis drug (ATD)-induced hepatitis.

METHODS

Patients who suffered from ATD-induced hepatitis were enrolled in the study. ATD-induced hepatitis was defined as an increase in liver transaminase levels that were more than three times the upper limit of normal. ATD-tolerant patients were used as a control. Patients were treated with first line ATD therapies including isoniazid, rifampicin, ethambutol, and pyrazinamide. We compared the genotype frequencies of the TNF-α polymorphism -308G/A in 77 patients with ATD-induced hepatitis and 229 ATD-tolerant patients.

RESULTS

The frequency of carrying the variant allele (AG or AA) was significantly higher in patients with ATD-induced hepatitis compared with ATD-tolerant patients [26.0% vs. 15.3%, P = 0.034, OR (95% CI) = 1.94 (1.04–3.64)] and the frequency of the A allele was significantly different between the two groups [0.143 vs. 0.079, P = 0.018, OR (95% CI) = 1.95 (1.11–3.44)].

CONCLUSION

These results reveal that the TNF-α genetic polymorphism -308G/A is significantly associated with ATD-induced hepatitis. This genetic variant may be a risk factor for ATD-induced hepatitis in individuals from Korea.

Sorafenib-induced liver failure: a case report and review of the literature

In patients with hepatocellular carcinoma characterized by vascular invasion and/or extrahepatic disease, Sorafenib is considered treatment of choice. Although mild liver test abnormalities were reported in less than 1% of the patients in the two large randomized, controlled phase III trials, four cases of severe acute Sorafenib-induced hepatitis have been described. One of these four cases died from liver failure. In this paper, a patient with HCC with lung metastases developed high fever and a severe hepatitis that rapidly evolved into liver coma and death, two weeks after the initiation of Sorafenib. Biochemical parameters pointed to a hepatocellular type of injury. Clinical and biochemical presentations were compatible with a drug-induced hypersensitivity syndrome such as it has mainly been described for aromatic anticonvulsants, sulphonamides, and allopurinol. We hypothesize that an underlying cytochrome P450 dysfunction with the presence of reactive drug metabolites might lead to this potentially fatal Sorafenib-induced severe liver dysfunction.

Acute hepatitis E infection accounts for some cases of suspected drug-induced liver injury

BACKGROUND & AIMS

The diagnosis of drug-induced liver injury relies on exclusion of other causes, including viral hepatitis A, B, and C. Hepatitis E virus (HEV) infection has been proposed as another cause of suspected drug-induced liver disease. We assessed the frequency of HEV infection among patients with drug-induced liver injury in the United States.

METHODS

The Drug-Induced Liver Injury Network (DILIN) is a prospective study of patients with suspected drug-induced liver injury; clinical information and biological samples are collected to investigate pathogenesis and disease progression. We analyzed serum samples, collected from patients enrolled in DILIN, for immunoglobulin (Ig) G and IgM against HEV; selected samples were tested for HEV RNA.

RESULTS

Among 318 patients with suspected drug-induced liver injury, 50 (16%) tested positive for anti-HEV IgG and 9 (3%) for anti-HEV IgM. The samples that contained anti-HEV IgM (collected 2 to 24 weeks after onset of symptoms) included 4 that tested positive for HEV RNA genotype 3. Samples from the 6-month follow-up visit were available from 4 patients; they were negative for anti-HEV IgM, but levels of anti-HEV IgG increased with time. Patients who had anti-HEV IgM were mostly older men (89%; mean age, 67 years), and 2 were human immunodeficiency virus positive. Clinical reassessment of the 9 patients with anti-HEV IgM indicated that acute hepatitis E was the most likely diagnosis for 7 and might be the primary diagnosis for 2.

CONCLUSIONS

HEV infection contributes to a small but important proportion of cases of acute liver injury that are suspected to be drug induced. Serologic testing for HEV infection should be performed, particularly if clinical features are compatible with acute viral hepatitis.

Recurrent drug-induced liver injury (DILI) with different drugs in the Spanish Registry: the dilemma of the relationship to autoimmune hepatitis

BACKGROUND & AIMS

Multiple instances of DILI in the same patient with drugs of similar structure or function as well as completely unrelated drugs are not well understood and poorly documented. We have sought evidence of the frequency and characteristics of patients who have experienced two DILI episodes due to different drugs.

METHODS

All cases of DILI systematically collected in the Spanish DILI Registry between 1994 and 2009 were retrieved. Data on demographics, clinical, laboratory and pathological findings, and outcome were analyzed.

RESULTS

Nine patients (mean age 67 years, four women) out of 742, 1.21%, had evidence of two DILI episodes caused by different drugs. In four cases DILI was associated with structurally related drugs and in an additional two cases the drugs had a common target. In another case, unrelated antibiotics were implicated. In only two cases, the two drugs/herbals were not related in structure or function. All but one patient exhibited hepatocellular damage. The type of damage was consistent in both DILI episodes. Four cases presented as autoimmune hepatitis (AIH) in the second episode.

CONCLUSIONS

Multiple episodes of DILI in association with different drugs occur infrequently. In each individual, the type of injury was similar during the two DILI episodes, regardless of the causative drug. Second episodes of DILI are more likely to be associated with features of AIH. It remains uncertain if this is drug-induced unmasking of true AIH or DILI with autoimmune features. These cases illustrate the dilemma faced by clinicians in distinguishing these possibilities.

Drug-Induced liver injury with hypersensitivity features has a better outcome: a single-center experience of 39 children and adolescents

Drug-induced liver injury (DILI) is rare in children and adolescents, and, consequently, data are remarkably limited. We analyzed the causes, clinical and biochemical features, natural history, and outcomes of children with DILI. Consecutive children with DILI from 1997 to 2004 (retrospective) and 2005 to 2010 (prospective) were studied based on standard criteria for DILI. Thirty-nine children constituted 8.7% of 450 cases of DILI. There were 22 boys and 17 girls. Median age was 16 years (range, 2.6-17). Combination antituberculous drugs were the most common cause (n = 22), followed by the anticonvulsants, phenytoin (n = 10) and carbamazepine (n = 6). All of the 16 children (41%) who developed hypersensitivity features, such as skin rashes, fever, lymphadenopathy, and/or eosinophilia, including the 3 with Stevens-Johnson syndrome, survived. Those with hypersensitivity presented earlier (24.5 versus 35 days; P = 0.24) had less severe disease (MELD, 16 versus 29; P = 0.01) and had no mortality (0/16 versus 12/23; P < 0.001), compared to those without hypersensitivity. The 12 fatalities were largely the result of antituberculous DILI (n = 11). The presence of encephalopathy and ascites were associated with mortality, along with hyperbilirubinemia, high international normalized ratio, and serum creatinine. According to the Roussel Uclaf Causality Assessment Method, 18 were highly probable, 14 probable, and 7 possible. Thirty-two children were hospitalized.

CONCLUSION

DILI is not uncommon in children and accounts for 8.7% of all patients with DILI. Antituberculous drugs and anticonvulsants are the leading causes of DILI in India. Overall mortality is high (30.7%), largely accounted by antituberculous drugs. Children with DILI and hypersensitivity features present early, have less severe disease, and, consequently, a better prognosis, compared to those without, and are often associated with anticonvulsants or sulfonamides.

Genetic association studies in drug-induced liver injury

A large number of case-control association studies on genetic susceptibility to drug-induced liver injury, involving both candidate gene and genome-wide association approaches, have now been reported. The strongest associations have been observed for human leukocyte antigen (HLA) class I and II genes and N-acetyltransferase 2 (NAT2). The associations with HLA class I and II genes are drug specific, though some apparently unrelated compounds show genetic associations with the same alleles. The underlying mechanism for the HLA association is likely to involve T-cell responses to either drug-protein adducts or to drug alone, but needs further investigation. The NAT2 association relates to liver injury induced by isoniazid, with most published studies finding an increased risk of injury in slow acetylators lacking NAT2 enzyme activity, presumably because of the accumulation of toxic metabolites. Other associations with genes relevant to drug disposition, innate immunity, oxidative stress, and mitochondrial function have also been reported, though these still need to be confirmed by replication in independent cohorts.

Causality assessment methods in drug induced liver injury: strengths and weaknesses

Diagnosis of drug-induced liver injury (DILI) remains a challenge and eagerly awaits the development of reliable hepatotoxicity biomarkers. Several methods have been developed in order to facilitate hepatotoxicity causality assessments. These methods can be divided into three categories: (1) expert judgement, (2) probabilistic approaches, and (3) algorithms or scales. The last category is further divided into general and liver-specific scales. The Council for International Organizations of Medical Sciences (CIOMS) scale, also referred to as the Roussel Uclaf Causality Assessment Method (RUCAM), although cumbersome and difficult to apply by physicians not acquainted with DILI, is used by many expert hepatologists, researchers, and regulatory authorities to assess the probability of suspected causal agents. However, several limitations of this scale have been brought to light, indicating that a number of adjustments are needed. This review is a detailed timely criticism to alert the readers of the limitations and give insight into what would be needed to improve the scale. Instructions on how to approach DILI diagnosis in practice are provided, using CIOMS as an aid to emphasize the topics to be addressed when assessing DILI cases. Amendments of the CIOMS scale in the form of applying authoritative evidence-based criteria, a simplified scoring system and appropriate weighting given to individual parameters based on statistical evaluations with large databases will provide wider applicability in the clinical setting.

Characteristics of idiosyncratic drug-induced liver injury in children: results from the DILIN prospective study

BACKGROUND

The spectrum and severity of idiosyncratic drug-induced liver injury (DILI) in children are not well established.

PATIENTS AND METHODS

The DILIN (Drug-Induced Liver Injury Network) Prospective Study is a longitudinal multicenter study designed to determine the etiologies, risk factors, and outcomes of suspected DILI. Between September 2004 and September 2009, 30 children ages 2 to 18 years with suspected DILI who met eligibility criteria were enrolled and studied for at least 6 months.

RESULTS

Mean age was 14 years; 70% were girls. Antimicrobial (50%) and central nervous system agents (40%) were the most commonly implicated drug classes, with minocycline (4), isoniazid (3), azithromycin (3), atomoxetine (3), and lamotrigine (3) the leading agents. Median time from drug initiation to symptom onset was 32 days. Peak (median) liver chemistries were aspartate aminotransferase 503  U/L, alanine aminotransferase 727  U/L, alkaline phosphatase 331  U/L, and total bilirubin 3.9  mg/dL. Autoantibodies were common (64%). Liver injury pattern was hepatocellular 78%, cholestatic 13%, and mixed 9%. The DILI episode was scored: mild 32%, moderate 44%, severe 20%, and fatal (within 6 months) 4%. Causality assessment was definite 36%, very likely 36%, probable 16%, possible 8%, and unlikely 4%. Seven percent had persistent liver test abnormalities at 6-month follow-up suggesting chronic DILI. Liver biopsies from 12 children most frequently demonstrated chronic hepatitis or bile duct injury.

CONCLUSIONS

Idiosyncratic DILI in children is most commonly caused by antimicrobial or central nervous system agents and usually presents with a hepatocellular injury pattern. The majority of patients recover, but morbidity and infrequent mortality are seen.

Accuracy and reproducibility of two scales in causality assessment of unexpected hepatotoxicity

WHAT IS KNOWN AND OBJECTIVE

There is almost no published information about reliability of scales for causality assessment in hepatotoxicity at pharmacovigilance centres. The aim of this study was to compare two commonly used scales in cases of unexpected hepatotoxicity, in evaluating their accuracy and reproducibility at pharmacovigilance centres (in signal detection).

METHODS

Two scales [Council for International Organizations of Medical Sciences or Rousel Uclaf Causality Assessment Method (CIOMS/RUCAM) and NARANJO] were compared in 19 cases of unexpected hepatotoxicity reported during 2004-2009. Data of the cases (with initial clinical assessments) were collected by a network of medical specialists using a structured reporting form. Later, two independent observers assessed each case using both scales. The accuracy and reproducibility of the scales were analysed by Kappa weighted (Kw) test.

RESULTS

  Both scales (CIOMS/RUCAM vs. NARANJO) showed moderate agreement with the initial clinical assessments (accuracy) for observer A (Kw: 0·56 vs. 0·60) and substantial agreement for observer B (Kw: 0·72 vs. 0·70), with high agreement between observers (Kw: 0·84 vs. 0·67). Both observers (A vs. B) found low agreement between scales (Kw: 0·21 vs. 0·50), with lower scores for the CIOMS/RUCAM scale in 11 and nine cases, respectively. For an early perception of unexpected serious reactions, the scale is more useful if it is not asked for 'previous knowledge' and if it gives higher causality score.

WHAT IS NEW AND CONCLUSION

The CIOMS/RUCAM scale showed similar accuracy, but better reproducibility (agreement between observers) than the NARANJO scale, and therefore is recommended for use at pharmacovigilance centres. Fine-tuning of the CIOMS/RUCAM method could contribute to better detection of unexpected hepatotoxicity.

Pathology of flupirtine-induced liver injury: a histological and clinical study of six cases

Drug-induced liver injury may cause impairment of liver function and is a leading cause of acute liver failure. Identification of the causative substance in patients receiving several drugs is often difficult in clinical practice. Evaluation of liver biopsies in suspected drug-induced injury is a challenging task that requires close clinico-pathological correlation. Recognizing a characteristic morphological pattern of liver injury may contribute to identification of the causative drug. Flupirtine, a non-opioid analgesic, has been reported to cause liver injury of idiosyncratic type in rare instances. We wished to characterize the histopathological features of flupirtine-induced liver injury, which have not been reported so far. Liver biopsies of five patients with severe liver injury and one explanted liver of a patient with flupirtine-induced acute liver failure that required transplantation were assessed. In addition clinical presentation and course were reviewed and clinical follow up was performed. Extensive perivenular necrosis with associated ceroid pigment-laden macrophages and a mild to moderate lymphocytic infiltrate was a common feature in all cases. Histological extent of liver necrosis corresponded well to serum amino-transferase levels. Accidental reexposure of one patient resulted in a plasma cell rich hepatitis with perivenular necrosis. This study provides evidence that flupirtine can cause substantial liver injury of hepatocellular type. Liver damage is associated with a characteristic morphological picture, the recognition of which will aid in causality assessment of drug-induced liver injury. Clinical and histological features raise the possibility of an immune-mediated toxicity.

Lapatinib-induced hepatitis: A case report

Lapatinib is an inhibitor of the tyrosine kinases of human epidermal growth factor receptor type 2 (HER2) and epidermal growth factor receptor type 1, with clinical activity in HER2-positive metastatic breast cancer. We present here a 60 year-old patient with metastatic breast cancer who presented with jaundice and increased serum aminotransferase levels and who had been treated with lapatinib for the previous 14 days. Laboratory tests excluded other causes of acute liver injury. Liver biopsy revealed lesions compatible with drug-induced hepatotoxicity. Bilirubin and liver enzymes returned to normal within three months of lapatinib discontinuation. Lapatinib should be included among the causes of drug-induced hepatitis.

Case definition and phenotype standardization in drug-induced liver injury

Drug-induced liver injury (DILI) is the most frequent reason cited for the withdrawal of approved drugs from the market and accounts for up to 15% of the cases of acute liver failure. Investigators around the globe have begun to identify and study patients with DILI; several large registries and tissue banks are being established. In order to gain the maximum scientific benefit from these efforts, the definitions and terminology related to the clinical phenotypes of DILI must be harmonized. For this purpose, an international DILI Expert Working Group of clinicians and scientists reviewed current DILI terminology and diagnostic criteria so as to develop more uniform criteria that would define and characterize the spectrum of clinical syndromes that constitute DILI. Consensus was established with respect to the threshold criteria for definition of a case as being DILI, the pattern of liver injury, causality assessment, severity, and chronicity. Consensus was also reached on approaches to characterizing DILI in the setting of chronic liver diseases, including autoimmune hepatitis (AIH).

[Hepatotoxicity, a global problem with local features: toward the creation of a Pan-American Hepatotoxicity Network]

Drug-induced liver damage is one of the most complex liver diseases due to its similar presentation to other acute or chronic liver processes, its potential severity and the absence of specific biomarkers to confirm diagnosis, which is based on clinical suspicion and exclusion of alternative causes. Because the drug development process fails to completely screen out hepatotoxic molecules and identify susceptible individuals, postmarketing pharmacovigilance remains essential. Hepatotoxicity registries are the ideal instrument for systematic and continual data collection, using preestablished criteria based on consensus. The present article briefly describes the contributions of the Spanish Hepatotoxicity Registry and those of other international registries. Hopefully, Latin American registries will be incorporated into existing initiatives, which will stimulate research and improve understanding of the complex mechanisms involved in this adverse reaction.

What are the best reference values for a normal serum alanine transaminase activity (ALT)? Impact on the presumed prevalence of drug induced liver injury (DILI)

BACKGROUND

In clinical research, the definition of the upper limit of normal (ULN) is rarely detailed. For alanine transaminase (ALT), there are several definitions of ULN-ALT but no recognized global reference. Furthermore the inter-laboratory variability of results expressed using ULN-ALT is higher than using the actual value of ULN expressed in IU/L. Regulatory agencies still use ULN-ALT for the definition of drug adverse events such as drug induced liver disease (DILI).

METHODS

We applied two extreme definitions of ULN-ALT (26 and 66 IU/L) in two populations with different liver disease risk: 7463 consecutive volunteers representative a low risk population, and 6865 consecutive patients hospitalized in a tertiary referral center. The same assay technique was used for both populations on fresh plasma in the same laboratory.

RESULTS

In the low risk population the liver disease estimates ranged from 0% to 1.99% according to ULN-ALT definition and gender; prevalence of liver disease as defined by Temple's criteria (3×ULN) decreased significantly with increased ULN-ALT threshold and prevalence of liver disease was lower in females compared to males (all P<0.001). In the high risk population the estimates of liver disease prevalence ranged from 0.78% to 15.85%; disease prevalence using both Temple's corollary and Hy's law criteria (3×ULN-ALT and bilirubin >34 μmol/L) decreased significantly with increased ULN-ALT threshold and females compared to males. In the low risk population the two major factors associated with ULN variability were gender and BMI.

CONCLUSION

Artificial statistical modifications of the procedures chosen for the ULN-ALT definition change dramatically the prevalence of DILI estimates. A consensus in liver disease definitions seems mandatory for DILI studies in order to prevent misleading conclusions.

Drug-induced liver injury: a summary of recent advances

INTRODUCTION

The knowledge base of drug-induced liver injury (DILI) continues to grow each year as additional drugs are identified as hepatotoxins. There is still a need to improve our ability to predict and diagnose DILI in the preclinical and post-approval settings.

AREAS COVERED

This article presents the new and updated DILI registries for 2010, including the latest information on the causes and outcomes of non-acetaminophen DILI cases in the US Acute Liver Failure Study Group database. As DILI is still largely a diagnosis of exclusion, it is appropriate that causality assessment instruments are again the subject of considerable discussion.

EXPERT OPINION

DILI research remains extremely active including studies aimed at being better able to identify causative agents, utilize potential biomarkers, predict who is at greatest risk of injury and manage outcomes. With respect to identifying DILI risk factors at the genetic level, the field is rapidly approaching the day where 'personalized medicine' (based on pharmacogenomics) will become a reality. A large single-center series from India reminds us that geography can influence the drugs responsible for liver injury; however, Hy's law remains universal. As our DILI knowledge continues to grow, it remains essential to keep abreast of the important changes reported each year.

Cholestatic jaundice, acute kidney injury and acute pancreatitis secondary to the recreational use of methandrostenolone: a case report

Introduction

Over the last few years the use of anabolic steroids has become increasingly common amongst amateur athletes and for aesthetic purposes. As a result, the adverse events related to their use are being seen more frequently. Methandrostenolone is an anabolic steroid which is widely available and has been used for both performance enhancement and aesthetic purposes. This drug has also been reported to cause cholestasis of the intra-hepatic bile ducts resulting in elevated aminotransferases, hyperbilirubinemia and clinical jaundice. However, to the best of our knowledge this agent has not been previously reported to cause pancreatitis or acute kidney injury.

Case presentation

In this paper, we report the case of a 50-year-old man of Indian descent who presented with a six week history of diffuse abdominal pain, anorexia and weight loss following an eight week cycle of methandrostenolone use. At initial presentation, his lipase level was 785 U/L, bilirubin was 922 μmol/L and creatinine was 200 U/L while his aspartate aminotransferase and alanine aminotransferase levels were only mildly elevated at 61 U/L and 56 U/L respectively. His lipase peaked on day nine at >3000 U/L whilst his creatinine level was 299 U/L. Imaging was consistent with acute pancreatitis while a liver biopsy was consistent with intra-hepatic cholestasis and a kidney biopsy revealed evidence of acute tubular necrosis.

Conclusion

Both acute pancreatitis and acute kidney injury have rarely been reported with anabolic steroid use and they have not been previously reported to occur in the same patient. This case demonstrates some potentially new and serious adverse consequences occurring with the use of anabolic steroids, of which physicians need to be aware.

Drug-induced autoimmune-like hepatitis

The clinical phenotype of classical autoimmune hepatitis can be mimicked by idiosyncratic drug-induced liver injury, and differentiation can be difficult. The goals of this review are to enumerate the major agents of drug-induced autoimmune-like hepatitis, describe the clinical findings and risk factors associated with it, detail the clinical tools by which to assess causality, discuss putative pathogenic mechanisms, and describe treatment and outcome. The frequency of drug-induced autoimmune-like hepatitis among patients with classical features of autoimmune hepatitis is 9%. Minocycline and nitrofurantoin are implicated in 90% of cases. Female predominance, acute onset, and absence of cirrhosis at presentation are important clinical manifestations. Genetic factors affecting phase I and phase II transformations of the drug, polymorphisms that protect against cellular oxidative stress, and human leukocyte antigens that modulate the immune response may be important pathogenic components. Clinical judgment is the mainstay of diagnosis as structured diagnostic methods for drug-induced liver injury are imperfect. The covalent binding of a reactive drug metabolite to a hepatocyte surface protein (commonly a phase I or phase II enzyme), formation of a neoantigen, activation of CD8 T lymphocytes with nonselective antigen receptors, and deficient immune regulatory mechanisms are the main bases for a transient loss of self-tolerance. Discontinuation of the offending drug is the essential treatment. Spontaneous improvement usually ensues within 1 month. Corticosteroid therapy is warranted for symptomatic severe disease, and it is almost invariably effective. Relapse after corticosteroid withdrawal probably does not occur, and its absence distinguishes drug-induced disease from classical autoimmune hepatitis.

Mechanisms of drug-induced liver injury: from bedside to bench

The low incidence of idiosyncratic drug-induced liver injury (DILI), together with the lack of a reliable diagnostic biomarker and robust preclinical and in vitro toxicology test systems for the condition have limited our ability to define the mechanisms of DILI. A notable exception is acetaminophen hepatotoxicity, which is associated with the formation of a well-characterized and highly reactive intermediate metabolite, N-acetyl-p-benzoquinone imine. However, studies have also suggested a role for the host immune response and variation in the expression of the lymphocyte CD44 gene in the pathogenesis of acetaminophen hepatotoxicity. A careful review of the laboratory, clinical and histological phenotype of patients with DILI can provide potential clues to the mechanisms of disease pathogenesis, as observed with fialuridine and valproate hepatotoxicity. In addition, the use of transcriptomic and genomic approaches in patients with well-characterized DILI has provided important insights into the involvement of the host immune response in the pathogenesis of hepatotoxicity associated with the administration of flucloxacillin, lumiracoxib or ximelagatran. This Review highlights new developments regarding the potential role of reactive metabolites, mitochondrial toxicity, host immune-response pathways and biliary transporters in the etiopathogenesis of DILI. Going forward, a bedside-to-bench approach could improve our understanding of the mechanisms and risk factors for DILI.

Rare incidence of methotrexate-specific lesions in liver biopsy of patients with arthritis and elevated liver enzymes

Introduction

The present study objective was to evaluate the incidence of methotrexate (MTX)-specific liver lesions from the analysis of a liver biopsy of inflammatory arthritis patients with elevated liver enzymes.

Methods

A case-control study was performed with 1,571 arthritis patients on long-term low-dose MTX therapy. Results of liver biopsy were analyzed in 41 patients with elevated liver enzymes. The expression of autoimmune markers was also assessed. This population was compared with 41 disease control subjects obtained from the same database, also on MTX but without elevated liver enzymes, matched for age, sex and rheumatic disease.

Results

Compared with the disease controls, patients with liver biopsy showed lower disease duration and lower MTX exposure, weekly and cumulative doses, reflecting shorter treatment duration due to liver abnormalities. Liver biopsies showed 17 autoimmune hepatitis-like (AIH-like) lesions, 13 nonalcoholic steatohepatitis-like lesions, seven limited liver lesions, and two primary biliary cirrhoses. However, MTX-specific lesions with dystrophic nuclei in hepatocytes were seen in only two cases. Liver biopsy lesions were associated with autoimmune markers (P = 0.007); notably, AIH-like lesions were associated with rheumatoid arthritis and with the presence of the HLA-DR shared epitope.

Conclusions

MTX-specific liver lesions are rarely observed in arthritis patients under long-term MTX therapy and elevated liver enzymes.