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

Herbal products and the liver: a review of adverse effects and mechanisms

Herbal products have been used for centuries among indigenous people to treat symptoms and illnesses. Recently, their use in Western countries has grown significantly, rivaling that of prescription medications. Currently, herbal products are used mainly for weight loss and bodybuilding purposes but also to improve well-being and symptoms of chronic diseases. Many people believe that because they are natural, they must be effective and safe; however, these beliefs are erroneous. Few herbal products have been studied in well-designed controlled trials of patients with liver or other diseases, despite testimony to the contrary. Moreover, current highly effective antiviral drugs make efforts to treat hepatitis C with herbal products redundant. Herbal products are no safer than conventional drugs and have caused liver injury severe enough to require transplantation or cause death. Furthermore, their efficacy, safety, and claims are not assessed by regulatory agencies, and there is uncertainty about their reported and unreported contents. We review the history of commonly used herbal products, as well as their purported efficacies and mechanisms and their adverse effects.

Liver biopsy in children: position paper of the ESPGHAN Hepatology Committee

Liver biopsy (LB) is still the criterion standard procedure for obtaining liver tissue for histopathological examination and a valuable tool in the diagnosis, prognosis, and management of many parenchymal liver diseases. The aim of this position paper is to summarise the present practice of paediatric LB and make recommendations about its performance. Although histological evaluation of the liver is important in assessing prognosis and exploring treatment, noninvasive techniques (ie, imaging, laboratory markers) may replace use of liver histology. The indications for LB are changing as present knowledge of aetiologies, pathomechanism, and therapeutic options in paediatric liver disease is evolving. Adult and paediatric literature was reviewed to assess the existing clinical practice of LB with focus on the technique, indications, risk of complications, and contraindications in paediatrics. This position paper presents types of LB, indications, complications, contraindications, and an essential checklist for paediatric LB.

Chronic liver disease in the human immunodeficiency virus patient

There are an estimated 40 million HIV infected individuals worldwide, with chronic liver disease being the 2nd leading cause of mortality in this population. Elevated liver functions are commonly noted in HIV patients and the etiologies are varied. Viral hepatitis B and C, fatty liver and drug induced liver injury are more common. Treatment options for viral hepatitis C are rapidly evolving and are promising, but treatments are limited for the other conditions and is primarily supportive. Opportunistic infections of the liver are now uncommon. Irrespective of etiology, management requires referral to specialized centers and with due diligence mortality can be reduced.

Drug-induced liver injury: an overview over the most critical compounds

There has been a substantial interest in drug-induced liver injury (DILI) recently. National Institutes of Health has sponsored a multicenter study in the USA for the last 10 years, which has collected valuable information in this context. Idiosyncratic DILI is like other adverse effects of drugs underestimated and underreported in most epidemiological studies. A recent prospective population-based study from Iceland found a crude incidence of approximately 19 cases per 100,000 and year. Antibiotic is the class of drugs most commonly implicated in patients with DILI. Amoxicillin-clavulanate continues to be the most commonly implicated agent occurring in approximately 1 out of 2,300 users. Drugs with the highest risk of DILI in the Icelandic study were azathioprine and infliximab. Although rare, statin-induced hepatotoxicity has been well documented. Liver injury associated with the use of herbal medicines and dietary supplements seems to be increasing. Information on the documented hepatotoxicity of drugs has recently been made easier by a website available in the public domain: LiverTox ( http://livertox.nlm.nih.gov ). Unfortunately, at the current time, pre-therapy risk assessment for DILI in the individual patient is difficult but previous well-documented hepatotoxicity is usually a contraindication for a subsequent treatment with the same drug.

Toxicity from repeated doses of acetaminophen in children: assessment of causality and dose in reported cases

Liver injury has been reported in children treated with repeated doses of acetaminophen. The objective of this study was to identify and validate reports of liver injury or death in children younger than 6 years who were administered repeated therapeutic doses of acetaminophen. We reviewed US Poison Center data, peer-reviewed literature, US Food and Drug Administration Adverse Event Reports, and US Manufacturer Safety Reports describing adverse effects after acetaminophen administration. Reports that described hepatic abnormalities (description of liver injury or abnormal laboratory testing) or death after acetaminophen administration to children younger than 6 years were included. The identified reports were double abstracted and then reviewed by an expert panel to determine if the hepatic injury was related to acetaminophen and whether the dose of acetaminophen was therapeutic (≤75 mg/kg) or supratherapeutic. Our search yielded 2531 reports of adverse events associated with acetaminophen use. From these cases, we identified 76 cases of hepatic injury and 26 deaths associated with repeated acetaminophen administration. There were 6 cases of hepatic abnormalities and no deaths associated with what our panel determined to be therapeutic doses. A large proportion of cases could not be fully evaluated due to incomplete case reporting. Although we identified numerous examples of liver injury and death after repeated doses of acetaminophen, all the deaths and all but 6 cases of hepatic abnormalities involved doses more than 75 mg/kg per day. This study suggests that the doses of less than 75 mg/kg per day of acetaminophen are safe for children younger than 6 years.

Anti-tumour necrosis factor agent and liver injury: Literature review, recommendations for management

Abnormalities in liver function tests, including transient and self-limiting hypertransaminasemia, cholestatic disease and hepatitis, can develop during treatment with anti-tumour-necrosis-factor (TNF) therapy. The optimal management of liver injury related to anti-TNF therapy is still a matter of debate. Although some authors recommend discontinuing treatment in case of both a rise of alanine aminotransferase more than 5 times the upper limit of normal, or the occurrence of jaundice, there are no standard guidelines for the management of anti-TNF-related liver injury. Bibliographical searches were performed in PubMed, using the following key words: inflammatory bowel disease (IBD); TNF inhibitors; hypertransaminasemia; drug-related liver injury; infliximab. According to published data, elevation of transaminases in patients with IBD treated with anti-TNF is a common finding, but resolution appears to be the usual outcome. Anti-TNF agents seem to be safe with a low risk of causing severe drug-related liver injury. According to our centre experience, we found that hypertransaminasemia was a common, mainly self-limiting finding in our IBD cohort and was not correlated to infliximab treatment on both univariate and multivariate analyses. An algorithm for the management of liver impairment occurring during anti-TNF treatment is also proposed and this highlights the need of a multidisciplinary approach and suggests liver biopsy as a key-point in the management decision in case of severe rise of transaminases. However, hepatic injury is generally self-limiting and drug withdrawal seems to be an exception.

Clinical features and outcomes of patients with drug-induced autoimmune hepatitis: a retrospective cohort study

BACKGROUND

Drugs and herbal products can induce autoimmune hepatitis. We assessed frequency and clinical outcomes of patients suffering from drug-induced autoimmune hepatitis.

METHODS

All patients with drug-induced liver injury admitted between 2000 and 2011 were retrospectively studied. Diagnoses of drug-induced autoimmune hepatitis and idiopathic autoimmune hepatitis were made according to simplified criteria. After discharge, all patients had regular follow-up and were contacted to update outcomes.

RESULTS

Among 10,270 in-hospital patients, 136 (1.3%) were diagnosed with drug-induced liver injury. Among them, 12 (8.8%) were diagnosed as drug-induced autoimmune hepatitis (41.7% males, age range 17-73); 8 (66.7%) were with jaundice at admission. Liver biopsies showed a pattern compatible with drug-induced autoimmune hepatitis, featured by severe portal inflammation and lymphoplasmacytic infiltrate. Drug-induced autoimmune hepatitis group had a shorter duration of drug intake, and higher values of transaminases and gamma globulins. All patients received immunosuppressive therapy with subsequent clinical remission, and five achieved a steroid-free long-term remission.

CONCLUSIONS

A diagnosis of drug-induced autoimmune hepatitis was quite rare in our cohort, and clinical pattern was similar to idiopathic autoimmune hepatitis. Severe portal inflammation, prominent portal-plasma cells, rosette formation and severe focal necrosis were significantly more frequent in drug-induced autoimmune hepatitis as compared to drug-induced liver injury.

A challenge for diagnosing acute liver injury with concomitant/sequential exposure to multiple drugs: can causality assessment scales be utilized to identify the offending drug?

Drug-induced hepatotoxicity most commonly manifests as an acute hepatitis syndrome and remains the leading cause of drug-induced death/mortality and the primary reason for withdrawal of drugs from the pharmaceutical market. We report a case of acute liver injury in a 12-year-old Hispanic boy, who received a series of five antibiotics (amoxicillin, ceftriaxone, vancomycin, ampicillin/sulbactam, and clindamycin) for cervical lymphadenitis/retropharyngeal cellulitis. Histopathology of the liver biopsy specimen revealed acute cholestatic hepatitis. All known causes of acute liver injury were appropriately excluded and (only) drug-induced liver injury was left as a cause of his cholestasis. Liver-specific causality assessment scales such as Council for the International Organization of Medical Sciences/Roussel Uclaf Causality Assessment Method scoring system (CIOMS/RUCAM), Maria and Victorino scale, and Digestive Disease Week-Japan were applied to seek the most likely offending drug. Although clindamycin is the most likely cause by clinical diagnosis, none of causality assessment scales aid in the diagnosis.

Intentional and inadvertent chemical contamination of food, water, and medication

Numerous examples of chemical contamination of food, water, or medication have led to steps by regulatory agencies to maintain the safety of this critical social infrastructure and supply chain. Identification of contaminant site is important. Environmental testing and biomonitoring can define the nature and extent of the event and are useful for providing objective information, but may be unavailable in time for clinical care. Clinical diagnosis should be based on toxidrome recognition and assessment of public health implications. There are several resources available to assist and these can be accessed through regional poison control centers or local/state public health departments.

Losartan-induced Ischemic Hepatocellular Hepatotoxicity: A Case Report and Literature Review

With the increasing use of various medications and supplements nowadays, the incidence of abnormal liver function tests and frank hepatic injury is has been increasing. Medications are now considered one of the most common causes of acute hepatic failure in the United States. Losartan was the first angiotensin 1 (AT1) receptor blocker approved by FDA for the treatment of arterial hypertension. It is a well-tolerated medication with few significant adverse effects. However, losartan-related hepatotoxicity has been reported rarely. We report a case of acute hepatic injury in an adult patient treated with losartan as a monotherapy for arterial hypertension.

Acute liver failure after valproate exposure in patients with POLG1 mutations and the prognosis after liver transplantation

Patients with mutations in the POLG1 gene encoding mitochondrial DNA polymerase gamma have an increased risk of valproate-induced liver failure. POLG1 mutations are common, and these patients often suffer from intractable seizures. The role of liver transplantation in the treatment of patients with mitochondrial diseases has been controversial. We studied valproate-induced liver failure associated with POLG1 mutations and the prognosis for these patients after liver transplantation. POLG1 was analyzed in blood DNA, mitochondrial DNA (mtDNA) was quantified in liver samples, and clinical data were collected. Five patients with valproate-induced liver failure associated with POLG1 mutations were retrospectively identified. Three patients were previously suspected to have Wilson's disease. Four patients with homozygous p.W748S and p.E1143G mutations had mtDNA depletion in the liver. One of these patients died before anticipated transplantation; the other 3 patients with liver transplantation have survived 4 to 19 years. Two patients have presented with occasional epileptic seizures, and 1 patient has been seizure-free for 11 years. One patient with a heterozygous p.Q1236H mutation (but without mtDNA depletion in the liver) died suddenly 2 years after liver transplantation. In conclusion, the POLG1 mutation status and the age at presentation of valproate-induced liver failure can affect the prognosis after liver transplantation. A heterozygous POLG1 p.Q1236H mutation was related to valproate-induced liver failure without mtDNA depletion, whereas patients homozygous for POLG1 p.W748S and p.E1143G mutations had mtDNA depletion. An analysis of the POLG1 gene should be performed for all patients with suspected mitochondrial disease before the introduction of valproate therapy, and treatment with valproic acid should be avoided in these patients.

Liver enzyme elevation during darunavir-based antiretroviral treatment in HIV-1-infected patients with or without hepatitis C coinfection: data from the ICONA foundation cohort

OBJECTIVES

To investigate differences in liver enzyme elevation (LEE) between HIV-infected patients with and without HCV coinfection who start a darunavir/ritonavir-containing regimen.

METHODS

HIV-infected patients enrolled in the Italian Cohort of Naïve to Antiretrovirals (ICONA) Foundation Study were included if they started darunavir/ritonavir for the first time. Patients were classified as not HCV coinfected, HCV active coinfected (HCV RNA positive), and HCV nonactive coinfected (HCV-Ab positive/HCV RNA negative). Time to LEE endpoint was defined using the ACTG toxicity scale, based on changes relative to baseline. Kaplan-Meier was used to estimate 1-year and 2-year probability of LEE. The incidence rate ratios (IRRs) of LEEs were estimated until the last follow-up (intention-to-treat analysis [ITT]) and up to darunavir/ritonavir discontinuation (on-treatment analysis [OT]).

RESULTS

Overall, 703 patients were included. Ninety-one were HCV-Ab positive; of those, 68 (9.7%) had active HCV coinfection. In 879 person-years of follow-up, 101 LEEs occurred (ITT). No severe hepatotoxicity event was registered in active HCV coinfected patients. HCV active coinfection was predictive of LEE in the overall population (OT: adjusted incidence rate ratio (IRR), 2.25; 95% CI, 0.70-7.24; P = .17; ITT: adjusted IRR, 3.62; 95% CI, 1.67-7.83; P < .001) and in naïve patients (OT: adjusted IRR, 6.29; 95% CI, 2.54-15.55; P = .00; ITT: adjusted IRR, 3.87; 95% CI, 0.99-15.16; P = .05).

CONCLUSIONS

No grade 3-4 LEEs occurred in HCV active coinfected patients. HCV active coinfected patients experienced low grade LEEs more frequently than HCV-Ab negative patients. Darunavir/ritonavir seems to be safe whatever the HCV status, when liver enzymes are carefully monitored.

Profiling cumulative proportional reporting ratios of drug-induced liver injury in the FDA Adverse Event Reporting System (FAERS) database

BACKGROUND

Early prediction and accurate characterization of risk for serious liver injury associated with newly marketed drugs remains an important challenge for clinicians, the pharmaceutical industry, and regulators. To date, a biomarker that specifically indicates exposure to a drug as the etiologic cause of liver injury has not been identified.

OBJECTIVES

Using cumulative proportional reporting ratios (PRRs), we investigated 'real-time' profiles of a set of pharmaceuticals, over the first 3 years of US marketing, for the signaling of clinically serious drug-induced liver injury (DILI) in a large spontaneous-reporting database.

METHODS

Using report counts of hepatic failure or clinically serious liver injury obtained from the FDA Adverse Events Reporting System (FAERS) database, PRRs of adverse drug event terms were calculated by division of counts of domestic reports of these events by counts of all serious adverse events for each of 13 selected drugs associated with a broad range of hepatotoxic risk (including three linked to only rare instances of clinically apparent liver injury) with reference to all other drugs in the database. Drug-specific cumulative PRRs were measured at successive intervals (calendar quarters) using cumulative tallies of FAERS reports to generate time-based profiles over the initial 3 years of US marketing.

RESULTS

In the set of drugs analyzed, those with no known hepatotoxic risk demonstrated time-based cumulative PRR profiles that approximate the background rates of hepatic failure and serious liver injury reported in the entire FAERS database. In contrast, those that were removed from marketing or subjected to marketing restrictions due to their potential to cause liver injury were associated with profiles of rapidly rising cumulative PRRs that were greater than 5 within the first 10 million domestic prescriptions or the first four quarters of US marketing. The systematic tracking and identification of rising PRRs for DILI associated with newly marketed pharmaceutical and biological agents is a valuable tool for identification of safety signals within the FAERS database.

LIMITATIONS

Disproportionality profiling of spontaneous reports in FAERS (e.g., cumulative PRR measurements), which signals an association between a recently marketed drug and liver injury, is not a method to quantitatively measure drug-related risk. Regulatory actions in response to emerging drug safety concerns often depend on an accurate assessment of risks using multiple sources of data and the consideration of overall benefits and risks of the agent. Causality must be determined through analysis of individual cases to exclude other etiologies of liver injury.

CONCLUSION

The FAERS database can be used to advance empiric hepatotoxicity time-trending reporting levels for newly marketed agents in order to rapidly identify recently launched potential hepatotoxic agents and initiate further evaluation.

Fulminant hepatitis following crizotinib administration for ALK-positive non-small-cell lung carcinoma

We herein report a case of fatal fulminant hepatitis secondary to crizotinib administration. The patient was 54-year-old female with a history of Hepatitis C infection (not current), dermatomyositis and steroid-induced diabetes mellitus. She was diagnosed with advanced lung adenocarcinoma with anaplastic lymphoma kinase rearrangement. We began 400 mg of crizotinib as first-line therapy. No adverse effects were seen until Day 16. On Day 29, she was admitted to hospital with elevated liver enzymes (aspartate aminotransferase 3236 IU/l, alanine aminotransferase 5201 IU/l) and coagulopathy (prothrombin time <10%), and was diagnosed with crizotinib-induced fulminant hepatitis. We started intensive care, using plasma exchange, continuous hemodiafiltration and high-dose steroid therapy. Unfortunately, she did not respond to therapies, and died on Day 36. The mechanism and risk factors of crizotinib-induced hepatotoxicity are uncertain. Physicians should be aware of possible adverse effects of crizotinib. A systemic survey is imperative to identify possible risk factors of crizotinib-related hepatotoxicity.

Assessing liver injury associated with antimycotics: Concise literature review and clues from data mining of the FAERS database

AIM

To inform clinicians on the level of hepatotoxic risk among antimycotics in the post-marketing setting, following the marketing suspension of oral ketoconazole for drug-induced liver injury (DILI).

METHODS

The publicly available international FAERS database (2004-2011) was used to extract DILI cases (including acute liver failure events), where antimycotics with systemic use or potential systemic absorption were reported as suspect or interacting agents. The reporting pattern was analyzed by calculating the reporting odds ratio and corresponding 95%CI, a measure of disproportionality, with time-trend analysis where appropriate.

RESULTS

From 1687284 reports submitted over the 8-year period, 68115 regarded liver injury. Of these, 2.9% are related to antimycotics (1964 cases, of which 112 of acute liver failure). Eleven systemic antimycotics (including ketoconazole and the newer triazole derivatives voriconazole and posaconazole) and terbinafine (used systemically to treat onychomicosis) generated a significant disproportionality, indicating a post-marketing signal of risk.

CONCLUSION

Virtually all antimycotics with systemic action or absorption are commonly reported in clinically significant cases of DILI. Clinicians must be aware of this aspect and monitor patients in case switch is considered, especially in critical poly-treated patients under chronic treatment.

Assessing liver injury associated with antimycotics: Concise literature review and clues from data mining of the FAERS database

AIM

To inform clinicians on the level of hepatotoxic risk among antimycotics in the post-marketing setting, following the marketing suspension of oral ketoconazole for drug-induced liver injury (DILI).

METHODS

The publicly available international FAERS database (2004-2011) was used to extract DILI cases (including acute liver failure events), where antimycotics with systemic use or potential systemic absorption were reported as suspect or interacting agents. The reporting pattern was analyzed by calculating the reporting odds ratio and corresponding 95%CI, a measure of disproportionality, with time-trend analysis where appropriate.

RESULTS

From 1687284 reports submitted over the 8-year period, 68115 regarded liver injury. Of these, 2.9% are related to antimycotics (1964 cases, of which 112 of acute liver failure). Eleven systemic antimycotics (including ketoconazole and the newer triazole derivatives voriconazole and posaconazole) and terbinafine (used systemically to treat onychomicosis) generated a significant disproportionality, indicating a post-marketing signal of risk.

CONCLUSION

Virtually all antimycotics with systemic action or absorption are commonly reported in clinically significant cases of DILI. Clinicians must be aware of this aspect and monitor patients in case switch is considered, especially in critical poly-treated patients under chronic treatment.

Use of Hy's law and a new composite algorithm to predict acute liver failure in patients with drug-induced liver injury

BACKGROUND & AIMS

Hy's Law, which states that hepatocellular drug-induced liver injury (DILI) with jaundice indicates a serious reaction, is used widely to determine risk for acute liver failure (ALF). We aimed to optimize the definition of Hy's Law and to develop a model for predicting ALF in patients with DILI.

METHODS

We collected data from 771 patients with DILI (805 episodes) from the Spanish DILI registry, from April 1994 through August 2012. We analyzed data collected at DILI recognition and at the time of peak levels of alanine aminotransferase (ALT) and total bilirubin (TBL).

RESULTS

Of the 771 patients with DILI, 32 developed ALF. Hepatocellular injury, female sex, high levels of TBL, and a high ratio of aspartate aminotransferase (AST):ALT were independent risk factors for ALF. We compared 3 ways to use Hy's Law to predict which patients would develop ALF; all included TBL greater than 2-fold the upper limit of normal (×ULN) and either ALT level greater than 3 × ULN, a ratio (R) value (ALT × ULN/alkaline phosphatase × ULN) of 5 or greater, or a new ratio (nR) value (ALT or AST, whichever produced the highest ×ULN/ alkaline phosphatase × ULN value) of 5 or greater. At recognition of DILI, the R- and nR-based models identified patients who developed ALF with 67% and 63% specificity, respectively, whereas use of only ALT level identified them with 44% specificity. However, the level of ALT and the nR model each identified patients who developed ALF with 90% sensitivity, whereas the R criteria identified them with 83% sensitivity. An equal number of patients who did and did not develop ALF had alkaline phosphatase levels greater than 2 × ULN. An algorithm based on AST level greater than 17.3 × ULN, TBL greater than 6.6 × ULN, and AST:ALT greater than 1.5 identified patients who developed ALF with 82% specificity and 80% sensitivity.

CONCLUSIONS

When applied at DILI recognition, the nR criteria for Hy's Law provides the best balance of sensitivity and specificity whereas our new composite algorithm provides additional specificity in predicting the ultimate development of ALF.

ACG Clinical Guideline: the diagnosis and management of idiosyncratic drug-induced liver injury

Idiosyncratic drug-induced liver injury (DILI) is a rare adverse drug reaction and it can lead to jaundice, liver failure, or even death. Antimicrobials and herbal and dietary supplements are among the most common therapeutic classes to cause DILI in the Western world. DILI is a diagnosis of exclusion and thus careful history taking and thorough work-up for competing etiologies are essential for its timely diagnosis. In this ACG Clinical Guideline, the authors present an evidence-based approach to diagnosis and management of DILI with special emphasis on DILI due to herbal and dietary supplements and DILI occurring in individuals with underlying liver disease.

Idiosyncratic drug-induced liver injury is associated with substantial morbidity and mortality within 6 months from onset

BACKGROUND & AIMS

Little is known about the incidence of drug-induced liver injury (DILI) and risk factors for adverse outcomes. We evaluated short-term outcomes of a large cohort of patients with DILI enrolled in an ongoing multicenter prospective study.

METHODS

Data were collected from 660 adults with definite, highly likely, or probable DILI. Regression methods were used to identify risk factors for early liver-related death or liver transplantation and chronic liver injury.

RESULTS

Patients' median age was 51.4 years; 59.5% were female and 59.1% required hospitalization. Within 6 months of DILI onset, 30 patients received liver transplants (4.5%; 95% confidence interval [CI], 3.0%-6.1%) and 32 died (5%; 95% CI, 3.2%-6.5%); 53% of the deaths were liver related. Asian race, absence of itching, lung disease, low serum albumin levels, low platelet counts, and high serum levels of alanine aminotransferase and total bilirubin at presentation were independent risk factors for reduced times to liver-related death or liver transplantation (C-statistic = 0.87). At 6 months after DILI onset, 18.9% of the 598 evaluable subjects had persistent liver damage. African-American race, higher serum levels of alkaline phosphatase, and prior heart disease or malignancy requiring treatment were independent risk factors for chronic DILI (C-statistic = 0.71).

CONCLUSIONS

Nearly 1 in 10 patients die or undergo liver transplantation within 6 months of DILI onset and nearly 1 in 5 of the remaining patients have evidence of persistent liver injury at 6 months. The profile of liver injury at presentation, initial severity, patient's race, and medical comorbidities are important determinants of the likelihood of death/transplantation or persistent liver injury within 6 months.

Herbs and liver injury: a clinical perspective

Despite a perception that herbal and dietary supplements are safe, devastating liver injury has been reported to result from their use. The difficulty in characterizing liver injury attributable to herbal and dietary supplements stems from the permissive regulatory environment, the complexity of marketed products, and underreporting by the patients who use them. Despite these limitations, researchers, clinicians, and regulators have increasing awareness of the need for study in this area.

Idiopathic acute liver injury in paediatric outpatients: incidence and signal detection in two European countries

BACKGROUND

Acute liver failure is idiopathic and drug-related in, respectively, around 50 and 15 % of children. Population-based, epidemiologic data about the pattern of disease manifestation and incidence of less severe acute liver injury, either idiopathic or potentially drug-attributed are limited in children and adolescents.

OBJECTIVES

(i) To assess the incidence of idiopathic acute liver injury (ALI) and its clinical features in children and adolescent outpatients; and (ii) to investigate the role of the drug as a potential cause of ALI which is considered idiopathic.

METHODS

A retrospective cohort study was performed during the years 2000-2008. Data were retrieved from three longitudinal electronic healthcare databases in two European countries: Pedianet and Health Search/CSD Longitudinal Patient Database from Italy and the Integrated Primary Care Information database from The Netherlands. Cases of idiopathic acute liver injury in population aged <18 years were identified by exclusion of all competing causes of liver injury (e.g. viral, autoimmune hepatitis), according to CIOMS criteria. The potential role of drug exposure as actual underlying cause of idiopathic ALI was detected through signal detection mining techniques. Both pooled and country-specific incidence rates [IR/100,000 person-years (PYs)] of idiopathic ALI and pooled adjusted rate ratios (RR) of drugs identified as a potential cause of idiopathic ALI, plus 95 % confidence intervals (CI) were estimated using the custom-built software Jerboa.

RESULTS

Among 785 definite cases of idiopathic ALI, the pooled IR was 62.4/100,000 PYs (95 % CI 58.1-66.8). The country-specific IR was higher in Italy (73.0/100,000 PYs, 95 % CI 67.8-78.4) than in The Netherlands (21.0/100,000 PYs, 95 % CI 16.0-27.2) and increased with age in both countries. Isolated elevations of liver enzymes were reported in around two-thirds of cases in Italy, while in The Netherlands the cases were more often identified by a combination of signs/symptoms. Among drugs detected as potential underlying cause of idiopathic ALI, clarithromycin (RR 25.9, 95 % CI 13.4-50), amoxicillin/clavulanic acid (RR 18.6, 95 % CI 11.3-30.6), and amoxicillin (RR 7.5, 95 % CI 3.4-16.8) were associated with the highest risk compared to non-use.

CONCLUSION

The incidence of idiopathic ALI in paediatrics is relatively low and comparable with adults. Clinical presentations differ between the two European countries. Signal detection in healthcare databases allowed identifying antibiotics as the drugs mostly associated with ALI with apparently unknown aetiology.

Hepatotoxicity caused by montelukast in a paediatric patient

Montelukast is a selective and competitive cysteinyl leukotriene receptor antagonist (CystLTRA) which is increasingly used for the treatment of allergic asthma. Recently, hepatotoxicity has been reported with this drug in adult patients, but only one letter to the editor has reported a case of probable montelukast-induced hepatotoxicity in a child. We present a case of a 3.5-year-old boy, receiving treatment with montelukast, who developed hepatocellular injury. The exclusion of other causes of increased activity of aminotransferases (viral, metabolic, autoimmune), improvement after dechallenge, the morphological findings and previous reports of comparable cases support the diagnosis of montelukast-induced liver injury in this boy. Physicians should strictly analyse indications for this drug and be aware of potential drug-induced liver disease caused by this agent. Therefore, the periodical assessment of aminotransferases should be recommended during treatment with this leukotriene modifier.

Value of liver elastography and abdominal ultrasound for detection of complications of allogeneic hemopoietic SCT

Hepatic complications contribute to morbidity and mortality after allogeneic hemopoietic SCT. Liver Doppler ultrasound and elastography represent promising methods for pretransplant risk assessment and early detection of complications. Ultrasound (liver and spleen size, liver perfusion) and elastography (transient elastography (TE); right liver lobe acoustic radiation force impulse imaging (r-ARFI); left liver lobe ARFI (l-ARFI)) were prospectively evaluated in patients with indications for allo-SCT. Measurements were performed before and repeatedly after SCT. Results were compared with the incidence of life-threatening complications and death during the first 150 days after SCT. Of 59 included patients, 16 suffered from major complications and 9 of them died within the follow-up period. At baseline, liver and spleen size, liver perfusion, TE and r-ARFI did not differ significantly between patients with and without severe complications. In contrast, l-ARFI was significantly elevated in patients who later developed severe complications (1.58±0.30 m/s vs 1.37±0.27 m/s, P=0.030). After SCT, l-ARFI values remained elevated and TE showed increasing liver stiffness in patients with complications. The value of conventional liver ultrasound for prediction of severe SCT complications is limited. Increased values for TE and l-ARFI are associated with severe SCT complications and demand further evaluation.

Drug-drug interactions with oral anti-HCV agents and idiosyncratic hepatotoxicity in the liver transplant setting

Studies of boceprevir and telaprevir based antiviral therapy in liver transplant (LT) recipients with hepatitis C genotype 1 infection have demonstrated dramatic increases in tacrolimus, cyclosporine, and mTOR inhibitor exposure. In addition to empiric dose reductions, daily monitoring of immunosuppressant blood levels is required when initiating as well as discontinuing the protease inhibitors to maximize patient safety. Although improved suppression of HCV replication is anticipated, 20 to 40% of treated subjects have required early treatment discontinuation due to various adverse events including anemia (100%), infection (30%), nephrotoxicity (20%) and rejection (5 to 10%). Simeprevir and faldaprevir will likely have improved efficacy and safety profiles but potential drug interactions with other OATP1B1 substrates and unconjugated hyperbilirubinemia are expected. In contrast, sofosbuvir and daclatasvir based antiviral therapy are not expected to lead to clinically significant drug-drug interactions in LT recipients but confirmatory studies are needed. Liver transplant recipients may also be at increased risk of developing drug induced liver injury (DILI). Establishing a diagnosis of DILI in the transplant setting is very difficult with the variable latency, laboratory features and histopathological manifestations of hepatotoxicity associated with a given drug, the need to exclude competing causes of allograft injury, and the lack of an objective and verifiable confirmatory test. Nonetheless, a heightened awareness of the possibility of DILI is warranted in light of the large number of medications used in LT recipients and the potential adverse impact that DILI may have on patient outcomes.

Pathogenesis of idiosyncratic drug-induced liver injury and clinical perspectives

Idiosyncratic drug-induced liver injury (DILI) is a rare disease that develops independently of drug dose, route, or duration of administration. Furthermore, idiosyncratic DILI is not a single disease entity but rather a spectrum of rare diseases with varying clinical, histological, and laboratory features. The pathogenesis of DILI is not fully understood. Standardization of the DILI nomenclature and methods to assess causality, along with the information provided by the LiverTox Web site, will harmonize and accelerate research on DILI. Studies of new serum biomarkers such as glutamate dehydrogenase, high mobility group box protein 1, and microRNA-122 could provide information for use in diagnosis and prognosis and provide important insights into the mechanisms of the pathogenesis of DILI. Single nucleotide polymorphisms in the HLA region have been associated with idiosyncratic hepatotoxicity attributed to flucloxacillin, ximelagatran, lapatinib, and amoxicillin-clavulanate. However, genome-wide association studies of pooled cases have not associated any genetic factors with idiosyncratic DILI. Whole genome and whole exome sequencing analyses are under way to study cases of DILI attributed to a single medication. Serum proteomic, transcriptome, and metabolome as well as intestinal microbiome analyses will increase our understanding of the mechanisms of this disorder. Further improvements to in vitro and in vivo test systems should advance our understanding of the causes, risk factors, and mechanisms of idiosyncratic DILI.

Profile of idiosyncratic drug induced liver injury in Latin America: an analysis of published reports

INTRODUCTION

Drug-induced liver injury (DILI) remains a major problem for drug development and represents a challenging diagnosis for clinicians. The absence of specific biomarkers for diagnosing DILI precludes the availability of reliable data on the epidemiology of the disease. In this study we aimed to describe the features of idiosyncratic hepatotoxicity reports in Latin American countries.

MATERIAL AND METHODS

A literature search was performed using the online version of MEDLINE, EMBASE, Scopus, Google Scholar and specific data bases from Latin America (LA) (Scielo, Lilacs) to identify any case report or case series of published DILI from 1996 to 2012. From 1996 to 2012, a total of 176 patients with DILI were published in LA, involving 53 suspicious drugs. The median age in the adult population of these patients was 55 years (17-82) with prevalence of women (67%). Among main therapeutic classes, the rank order was led by non-steroidal anti-inflammatory (61 cases) and systemic antibacterial drugs (37 cases). Nimesulide was the individual drug responsible for the highest number of cases (53), followed by cyproterone acetate (18), nitrofurantoin (17), antituberculous drugs (13) and flutamide (12). Thirty two percent of published cases evolved to acute liver failure (ALF), and half of the subjects required liver transplantation or eventually died.

CONCLUSIONS

This study represents the first structured attempt to assess the spectrum of DILI profile in LA. The establishment of a Latin American registry to collect prospective DILI cases using a standardized protocol will advance our knowledge about idiosyncratic DILI in this region.

Hepatic histological findings in suspected drug-induced liver injury: systematic evaluation and clinical associations

Drug-induced liver injury (DILI) is considered to be a diagnosis of exclusion. Liver biopsy may contribute to diagnostic accuracy, but the histological features of DILI and their relationship to biochemical parameters and outcomes are not well defined. We have classified the pathological pattern of liver injury and systematically evaluated histological changes in liver biopsies obtained from 249 patients with suspected DILI enrolled in the prospective, observational study conducted by the Drug Induced Liver Injury Network. Histological features were analyzed for their frequency within different clinical phenotypes of liver injury and to identify associations between clinical and laboratory findings and histological features. The most common histological patterns were acute (21%) and chronic hepatitis (14%), acute (9%) and chronic cholestasis (10%), and cholestatic hepatitis (29%). Liver histology from 128 patients presenting with hepatocellular injury had more severe inflammation, necrosis, and apoptosis and more frequently demonstrated lobular disarray, rosette formation, and hemorrhage than those with cholestasis. Conversely, histology of the 73 patients with cholestatic injury more often demonstrated bile plugs and duct paucity. Severe or fatal hepatic injury in 46 patients was associated with higher degrees of necrosis, fibrosis stage, microvesicular steatosis, and ductular reaction among other findings, whereas eosinophils and granulomas were found more often in those with milder injury.

CONCLUSION

We describe an approach for evaluating liver histology in DILI and demonstrate numerous associations between pathological findings and clinical presentations that may serve as a foundation for future studies correlating DILI pathology with its causality and outcome.

Drug-induced liver disease: Risk factors and intervention measures

AIM: To investigate the risk factors for drug-induced liver disease (DILD), and to explore preventive measures and clinical nursing interventions.

METHODS: Three hundred and fifteen patients treated with hepatotoxic drugs were divided into 2 groups: DILD group (n = 53) and non-DILD group (n = 262). Baseline data including gender, age, body mass index, nutritional status, history of drug allergy, history of drinking and smoking were analyzed by univariate analysis and Logistic regression analysis to explore the risk factors for DILD.

RESULTS: The incidence of DILD was 16.8%. HBs-Ag positivity, history of liver diseases, obesity, diabetes, cardiovascular disease, smoking and alcohol drinking are risk factors for DILD.

CONCLUSION: HBsAg positivity, history of liver diseases, obesity, diabetes, cardiovascular disease, smoking and alcohol drinking are risk factors for DILD. Timely and effective prevention, therapy and nursing intervention can help reduce the morbidity of DILD.

Drug and herb induced liver injury: Council for International Organizations of Medical Sciences scale for causality assessment

Causality assessment of suspected drug induced liver injury (DILI) and herb induced liver injury (HILI) is hampered by the lack of a standardized approach to be used by attending physicians and at various subsequent evaluating levels. The aim of this review was to analyze the suitability of the liver specific Council for International Organizations of Medical Sciences (CIOMS) scale as a standard tool for causality assessment in DILI and HILI cases. PubMed database was searched for the following terms: drug induced liver injury; herb induced liver injury; DILI causality assessment; and HILI causality assessment. The strength of the CIOMS lies in its potential as a standardized scale for DILI and HILI causality assessment. Other advantages include its liver specificity and its validation for hepatotoxicity with excellent sensitivity, specificity and predictive validity, based on cases with a positive reexposure test. This scale allows prospective collection of all relevant data required for a valid causality assessment. It does not require expert knowledge in hepatotoxicity and its results may subsequently be refined. Weaknesses of the CIOMS scale include the limited exclusion of alternative causes and qualitatively graded risk factors. In conclusion, CIOMS appears to be suitable as a standard scale for attending physicians, regulatory agencies, expert panels and other scientists to provide a standardized, reproducible causality assessment in suspected DILI and HILI cases, applicable primarily at all assessing levels involved.

Drug-induced liver injury

Drug hepatoxicity can be nonidiosyncratic (predictable), as in the case of acetaminophen, or idiosyncratic (unpredictable). This review article focuses primarily on idiosyncratic drug-induced liver injury (DILI). New epidemiologic data suggest that approximately 20 new cases of DILI per 100,000 persons occur each year. Idiosyncratic DILI accounts for 11% of the cases of acute liver failure in the United States. Risk factors for DILI include medication dose, drug lipophilicity, and extent of hepatic metabolism. There is mixed evidence to support the role of host factors such as age, sex, and chronic liver disease in the development of DILI. For specific drugs, a genetic predisposition appears to be a risk factor for DILI. Suspected cases of idiosyncratic DILI should be categorized as hepatitic, cholestatic, or mixed on the basis of the degree/ratio of abnormalities in the alanine aminotransferase and alkaline phosphatase. A careful evaluation for other causes of liver disease should be performed, though a liver biopsy is rarely needed. There is evidence that some patients with DILI may actually have hepatitis E and this diagnosis should be considered. Amoxicillin/clavulanate isoniazid, and nonsteroidal anti-inflammatory drugs are among the most common causes of DILI. Drug discontinuation or dechallenge should lead to an improvement in liver biochemistries in most patients, though a bilirubin value of more than 3 g/dL is associated with mortality of at least 10%. New biomarkers for DILI using proteomics and micro RNA appear promising but require further study. New studies on drugs with potential for causing DILI are reviewed herein, including tumor necrosis factor-alpha antagonists, fluoroquinolones, tyrosine kinase inhibitors, statins, and supplements. PubMed was used with search terms of drug induced liver injury OR DILI with filter settings of "English language" and "humans" and custom date range of "January 1, 2000." The authors also manually searched bibliographies from key references and included seminal references before the year 2000.

Female gender as a susceptibility factor for drug-induced liver injury

Adverse drug reactions (ADRs) can involve all tissues and organs, but liver injuries are considered among the most serious. A number of prospective, multicenter studies have confirmed a higher risk of ADRs in general among female subjects compared to a male cohort. Although drug-induced liver injury (DILI) is infrequently encountered, the preponderance of evidence suggests that women appear to be more susceptible than men to fulminate hepatic/acute liver failure especially in response to some anti-infective drugs and to autoimmune-like hepatitis following exposure to certain other therapeutic drugs. A number of hypotheses have been proposed to explain this sex difference in susceptibility to DILI. Collectively, these hypotheses suggest three basic sex-dependent mechanisms that include differences in various aspects of drug pharmacokinetics (PK) or pharmacodynamics following the administration of certain drugs; specific hormonal effects or interactions with immunomodulating agents or signaling molecules; and differences in the adverse response of the immune system to some drugs, reactive drug metabolites, or drug-protein adducts. At the preclinical drug safety stage, there is a need for more research on hormonal effects on drug PK and for additional research on gender differences in aberrant immune responses that may lead to idiosyncratic DILI in some female patients. Because the detection of rare but serious hepatic ADRs requires the exposure of very large patient populations, pharmacovigilance networks will continue to play a key role in the postmarketing surveillance for their detection and reporting.

Idiosyncratic drug-induced liver injury: an update on the 2007 overview

INTRODUCTION

Idiosyncratic drug induced liver injury (DILI) is rare, with an incidence of approximately 19 per 100,000 treated individuals.

AREAS COVERED

An update on the epidemiology, pathogenic mechanisms, diagnosis, outcome, risk factors for idiosyncratic drug-induced hepatotoxicity, specific classes of drug hepatotoxicity and biomarkers to predict DILI are covered. Cumulative drug exposure and HLA phenotypes play an important role in the pathogenesis of DILI. Patients who present with suspected DILI and jaundice should have biliary obstruction and acute viral hepatitis, including hepatitis E excluded. Immune-mediated DILI will respond to steroid therapy. Patients with an elevated bilirubin and a hepatocellular pattern of liver function tests have severe liver injury with a mortality of greater than 10% and a risk of acute liver failure. Women have an increased risk of hepatocellular DILI. Antibiotics, anticonvulsants, and antidepressant therapy remain the commonest causes of DILI in the Western Hemisphere. Statin therapy rarely causes severe liver injury.

EXPERT OPINION

The establishment of prospective registries for DILI has provided valuable data on the pathogenesis and outcome of DILI. Drug-specific computerised causality assessment tools should improve the diagnosis of DILI. The clinical utility of genetic polymorphisms associated with drug-specific DILI is limited.

Genetic risk factors for drug-induced liver injury in rheumatoid arthritis patients using low-dose methotrexate

Low-dose methotrexate (MTX) is part of the mainstay of rheumatoid arthritis treatment. Hepatotoxicity is among the most feared side effects of low-dose MTX and is associated with increased morbidity. At present, histological evaluation of liver biopsies is the gold standard to retrospectively diagnose MTX-induced liver damage. Genetic markers present an interesting opportunity to preemptively identify patients at risk for MTX-induced hepatotoxicity. Here, we will review the literature on candidate genetic markers for the risk of MTX-induced hepatotoxicity. These candidate genetic markers include polymorphisms in the gene encoding the enzyme MTHFR.

Successful treatment of drug-induced acute liver failure with high-volume plasma exchange

We report two patients with drug-induced liver injury (DILI)-related acute liver failure (ALF) who were successfully treated with high-volume plasma exchange without liver transplantation. The first patient was a 66-year-old man admitted because of a perforated duodenal ulcer complicated with peritonitis and septic shock. After treatment with multiple antibiotics, the patient developed DILI and ALF. Grade 3 hepatic encephalopathy and profound jaundice were present. Symptoms and signs of ALF improved dramatically after initiation of plasma exchange. The patient was discharged uneventfully. The second patient was a 94-year-old man admitted for treatment of newly diagnosed pulmonary tuberculosis. DILI and ALF developed 5 days after initiation of anti-tuberculosis treatment. Grade 4 hepatic encephalopathy was present. After plasma exchange, the patient's level of consciousness improved dramatically, and he recovered from ALF. These 2 cases show the potential of plasma exchange in the treatment of DILI despite occurrence acute liver failure.

Presentation and outcomes with clinically apparent interferon beta hepatotoxicity

AIMS

The aim of this study was to describe the presenting features and outcomes of consecutive patients with liver injury attributed to interferon beta.

METHODS

The presenting features of eight subjects with clinically apparent liver injury attributed to interferon beta enrolled in the U.S. Drug-Induced Liver Injury Network (DILIN) prospective registry between 2004 and 2010 were reviewed and compared to 11 published reports of symptomatic hepatotoxicity.

RESULTS

All eight of the DILIN patients were women, 75 % were Caucasian and the mean age was 49 years. Most subjects presented with an acute hepatocellular injury pattern and mean serum alanine aminotransferase (ALT) levels were 725 ± 593 U/L. The median duration of interferon beta use before injury onset was 462 days, and four patients had been treated for more than a year. No patient had detectable antinuclear or smooth muscle antibodies. One patient died of acute liver failure and the remaining patients usually recovered within 2-3 months. Causality assessment scored three cases as definite, three highly likely, one probable and one possible. Eleven additional published cases were all women, mean age was 40 years, mean ALT at onset 840 U/L, and 7 (63 %) had autoantibodies. Liver histology in three cases from DILIN and nine from the literature commented upon centrilobular (zone 3) necrosis and infiltrates with lymphocytes and plasma cells.

CONCLUSIONS

Interferon beta hepatotoxicity occurs mostly in women and has a variable, but often prolonged time to onset. Most patients have self-limited acute hepatocellular liver injury but several have required liver transplantation or died of acute liver failure. Liver histology available in three cases demonstrated zone 3 necrosis and autoimmune features suggestive of an immunologic basis to this adverse drug reaction.

Liver injury from tumor necrosis factor-α antagonists: analysis of thirty-four cases

BACKGROUND & AIMS

Tumor necrosis factor (TNF)-α antagonists have been associated with drug-induced liver injury (DILI). We reviewed cases of DILI in the United States to identify those associated with use of TNF-α antagonists.

METHODS

We searched the U.S. DILI Network (DILIN) database, from 2003 to 2011, for cases associated with TNF-α antagonists. Mean Roussel-Uclaf Causality Assessment Method scores were calculated. A DILIN severity score was assigned according to a previously published scale, and we identified 6 subjects likely to have DILI associated with use of TNF-α antagonists. We also searched PubMed for articles that reported hepatotoxicity from TNF-α antagonists, identifying 28 additional cases suitable for analysis.

RESULTS

The drugs presumed to have caused DILI were infliximab (n = 26), etanercept (n = 4), and adalimumab (n = 4). The anti-TNF-α agent was the probable cause of 12 cases of DILI (35%), a very likely cause for 21 (62%), and a definite cause for 1 (3%). Median latency was 13 weeks (range, 2-104); however, 7 cases (20%) had latency periods longer than 24 weeks. Twenty-two of 33 subjects who underwent serologic analysis (67%) tested positive for anti-nuclear and/or smooth muscle antibodies. Of these 22, 17 underwent liver biopsy; 15 subjects had clear features of autoimmunity. The 22 subjects with autoimmune features had longer median latency (16 vs 10 weeks) and higher peak levels of alanine aminotransferase (784 vs 528 U/L) than the 12 without such features. There was 1 case of severe cholestasis. All but one subject improved after discontinuation of the implicated drug; 12 subjects received corticosteroid therapy. No deaths were attributed to liver injury, although one patient with preexistent cirrhosis required liver transplantation.

CONCLUSIONS

Acute liver injury caused by TNF-α antagonists may be a class effect because multiple agents in this category have been implicated. The most common presentation is an autoimmune phenotype with marked hepatocellular injury, but a mixed non-autoimmune pattern or predominant cholestasis also occurs. The prognosis is usually good after drug discontinuation, although some patients may benefit from a course of corticosteroids. ClinicalTrials.gov: Number, NCT00345930.

Liver injury from tumor necrosis factor-α antagonists: analysis of thirty-four cases

BACKGROUND & AIMS

Tumor necrosis factor (TNF)-α antagonists have been associated with drug-induced liver injury (DILI). We reviewed cases of DILI in the United States to identify those associated with use of TNF-α antagonists.

METHODS

We searched the U.S. DILI Network (DILIN) database, from 2003 to 2011, for cases associated with TNF-α antagonists. Mean Roussel-Uclaf Causality Assessment Method scores were calculated. A DILIN severity score was assigned according to a previously published scale, and we identified 6 subjects likely to have DILI associated with use of TNF-α antagonists. We also searched PubMed for articles that reported hepatotoxicity from TNF-α antagonists, identifying 28 additional cases suitable for analysis.

RESULTS

The drugs presumed to have caused DILI were infliximab (n = 26), etanercept (n = 4), and adalimumab (n = 4). The anti-TNF-α agent was the probable cause of 12 cases of DILI (35%), a very likely cause for 21 (62%), and a definite cause for 1 (3%). Median latency was 13 weeks (range, 2-104); however, 7 cases (20%) had latency periods longer than 24 weeks. Twenty-two of 33 subjects who underwent serologic analysis (67%) tested positive for anti-nuclear and/or smooth muscle antibodies. Of these 22, 17 underwent liver biopsy; 15 subjects had clear features of autoimmunity. The 22 subjects with autoimmune features had longer median latency (16 vs 10 weeks) and higher peak levels of alanine aminotransferase (784 vs 528 U/L) than the 12 without such features. There was 1 case of severe cholestasis. All but one subject improved after discontinuation of the implicated drug; 12 subjects received corticosteroid therapy. No deaths were attributed to liver injury, although one patient with preexistent cirrhosis required liver transplantation.

CONCLUSIONS

Acute liver injury caused by TNF-α antagonists may be a class effect because multiple agents in this category have been implicated. The most common presentation is an autoimmune phenotype with marked hepatocellular injury, but a mixed non-autoimmune pattern or predominant cholestasis also occurs. The prognosis is usually good after drug discontinuation, although some patients may benefit from a course of corticosteroids. ClinicalTrials.gov: Number, NCT00345930.

Characteristics of liver injury in drug-induced systemic hypersensitivity reactions

BACKGROUND

The liver is the most commonly involved internal organ in drug-induced systemic hypersensitivity. However, data obtained from these patients have yet to be analyzed in depth with respect to liver injury.

METHODS

The medical records of 136 patients who developed delayed-type drug hypersensitivity were reviewed at a tertiary referral hospital. Culprit drugs, the pattern and degree of liver injury, and the effect of systemic corticosteroids were evaluated in the group of patients with drug-induced systemic hypersensitivity and liver dysfunction (aspartate aminotransferase or alanine aminotransferase ≥80 IU/L). Clinical characteristics of patients with drug-induced systemic hypersensitivity and liver injury were analyzed.

RESULTS

Among the 61 patients with drug-induced systemic hypersensitivity and liver dysfunction, the clinical phenotypes were drug reaction with eosinophilia and systemic symptoms (n = 29, 48%), Stevens-Johnson syndrome/toxic epidermal necrolysis (n = 11, 18%), and maculopapular rash (n = 17, 28%). Antibiotics (n = 27, 44%) were the most common cause of drug-induced systemic hypersensitivity with liver dysfunction. Whereas patients with Stevens-Johnson syndrome/toxic epidermal necrolysis had mild hepatocellular-type liver injury of relatively brief duration, those with drug reaction with eosinophilia and systemic symptoms/drug-induced hypersensitivity syndrome had more severe and prolonged hepatocellular injury in addition to moderate to severe cholestatic-type liver injury. The use of systemic corticosteroids did not significantly affect either recovery from liver injury or mortality.

LIMITATIONS

This study was retrospective and the number of subjects was small.

CONCLUSION

The results suggest that the severity, pattern, and duration of liver injury differ according to the drug-hypersensitivity phenotype. Further studies are needed to evaluate the role of systemic corticosteroids in drug-induced systemic hypersensitivity and liver injury.

Bleeding complications and liver injuries during phenprocoumon treatment: a multicentre prospective observational study in internal medicine departments

BACKGROUND

Even after the recent approval of newer oral anticoagulants for clinical use, the vitamin K antagonist phenprocoumon remains an important treatment option for many patients. In order to quantify the hitherto "accepted" risks of phenprocoumon treatment, we analyzed adverse drug reactions (ADRs) that led to hospitalization on the internal medicine wards of four German pharmacovigilance centers.

METHODS

We prospectively analyzed ADRs leading to hospitalization on the internal medicine wards of the hospitals belonging to the German Network of Regional Pharmacovigilance Centers (Rostock, Greifswald, Jena, and the Sophien- und Hufeland-Klinikum in Weimar) in the years 2000 to 2008.

RESULTS

The 851 patients hospitalized for a phenprocoumon-associated ADR accounted for 12.4% of the 6887 ADR-related hospitalizations in the period of the study. 723 (85%) were admitted for a hemorrhage, usually in the gastrointestinal tract (482 patients); 8 patients died as a consequence of hemorrhage associated with phenprocoumon exposure. Using drug utilization data for the catchment areas of the participating hospitals, we calculate a rate of 5 to 7 hemorrhages leading to hospitalization in an internal medicine ward per 1000 patient-years under phenprocoumon treatment. One-third of the patients who had a hemorrhage were taking other interacting drugs, mainly inhibitors of platelet aggregation and non-steroidal anti-inflammatory drugs. Among the patients who were taking phenprocoumon because of a history of thromboembolic events or for atrial fibrillation, 60% to 70% of those who had hemorrhages had an international normalized ratio (INR) that was above the upper limit of the therapeutic range. Phenprocoumon-associated impairment of liver function arose in 23 patients (2.7%).

CONCLUSION

In this study, about one-eighth of all ADR-related admissions to hospital internal medicine wards were associated with phenprocoumon. There is a need for a comparative risk-benefit assessment of phenprocoumon and the newer oral anticoagulants under real-life conditions.

Suspected herbal hepatotoxicity: requirements for appropriate causality assessment by the US Pharmacopeia

The aim of this current opinion report is to discuss relevant issues of regulatory causality assessment methods related to initially suspected herb-induced liver injury (HILI). Herbal hepatotoxicity represents a major clinical, regulatory and public challenge since its diagnosis may be difficult to be established, requiring a sophisticated approach that includes a liver-specific and validated causality assessment method. In cases of primarily suspected HILI, however, problems emerged when the US Pharmacopeia (USP) published results with causality assessments of liver disease cases. In these studies, herbal drugs and herbal dietary supplements were considered as causative products based on causality attribution by a shortened version of the Naranjo scale. However, the Naranjo scale is not liver specific and not validated for liver toxicity, and these shortcomings also apply to its shortened and thereby modified version. Consequently, these results were questioned and considered invalid, requiring re-evaluation with a liver-specific causality assessment method validated for hepatotoxicity, such as the scale of the Council for International Organizations of Medical Sciences (CIOMS) or its validated update. In essence, the USP and other regulatory agencies should apply validated liver-specific causality assessment methods rather than liver unspecific and not validated assessment methods in suspected HILI cases.

Hepatoxicity of new antiretrovirals: a systematic review

There has been a major paradigm shift in the management of HIV infected patients, with earlier initiation of antiretroviral treatment and lifelong exposure to drugs for which long-term safety issues must be faced by clinicians. Within the past 5 years, new drugs from both previously established and novel therapeutic classes have been released that tend to be safer and more efficient than their former combinations. Although hepatotoxicity was one of the most common side effects from initial antiretrovirals, phase II/III safety data regarding liver tolerance from more recent drugs are reassuring. However, data on the long-term exposure to these therapeutic options are needed, and a handful of case reports are emerging, reporting rare but potentially life-threatening adverse hepatic events in patients with hepatitis co-infection or taking other hepatotoxic drugs.