Ibuprofen-induced hepatotoxicity in patients with chronic hepatitis C: a case series

2022 KLCA-NCC Korea practice guidelines for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

2022 KLCA-NCC Korea Practice Guidelines for the Management of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

2022 KLCA-NCC Korea practice guidelines for the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer worldwide and the fourth most common cancer among men in South Korea, where the prevalence of chronic hepatitis B infection is high in middle and old age. The current practice guidelines will provide useful and sensible advice for the clinical management of patients with HCC. A total of 49 experts in the fields of hepatology, oncology, surgery, radiology, and radiation oncology from the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2018 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions. These guidelines provide useful information and direction for all clinicians, trainees, and researchers in the diagnosis and treatment of HCC.

Ibuprofen-based advanced therapeutics: breaking the inflammatory link in cancer, neurodegeneration, and diseases

Ibuprofen is a classical nonsteroidal anti-inflammatory drug (NSAID) highly prescribed to reduce acute pain and inflammation under an array of conditions, including rheumatoid arthritis, osteoarthritis, dysmenorrhea, and gout. Ibuprofen acts as a potential inhibitor for cyclooxygenase enzymes (COX-1 and COX-2). In the past few decades, research on this small molecule has led to identifying other possible therapeutic benefits. Anti-tumorigenic and neuroprotective functions of Ibuprofen are majorly recognized in recent literature and need further consideration. Additionally, several other roles of this anti-inflammatory molecule have been discovered and subjected to experimental assessment in various diseases. However, the major challenge faced by Ibuprofen and other drugs of similar classes is their side effects, and tendency to cause gastrointestinal injury, generate cardiovascular risks, modulate hepatic and acute kidney diseases. Future research should also be conducted to deduce new methods and approaches of suppressing the unwanted toxic changes mediated by these drugs and develop new therapeutic avenues so that these small molecules continue to serve the purposes. This article primarily aims to develop a comprehensive and better understanding of Ibuprofen, its pharmacological features, therapeutic benefits, and possible but less understood medicinal properties apart from major challenges in its future application.KEY POINTSIbuprofen, an NSAID, is a classical anti-inflammatory therapeutic agent.Pro-apoptotic roles of NSAIDs have been explored in detail in the past, holding the key in anti-cancer therapies.Excessive and continuous use of NSAIDs may have several side effects and multiple organ damage.Hyperactivated Inflammation initiates multifold detrimental changes in multiple pathological conditions.Targeting inflammatory pathways hold the key to several therapeutic strategies against many diseases, including cancer, microbial infections, multiple sclerosis, and many other brain diseases.

Ibuprofen Increases the Hepatotoxicity of Ethanol through Potentiating Oxidative Stress

Over 30 million prescriptions of NSAIDs (non-steroidal anti-inflammatory drugs) are issued every year. Considering that these drugs are available without a prescription as over the counter (OTC) drugs, their use will be astronomical. With the increasing use of NSAIDs, their adverse effects are drawing attention. Especially, stomach bleeding, kidney toxicity, liver toxicity, and neurological toxicity are reported as common. Ibuprofen, one of the extensively used NSAIDs along with aspirin, can also induce liver toxicity, but few studies are addressing this point. Here we examined the liver toxicity of ibuprofen and investigated whether co-exposure to ethanol can manifest synergistic effects. We employed 2D and 3D cultured human hepatoma cells, HepG2 to examine the synergistic hepatotoxicity of ibuprofen and alcohol concerning cell viability, morphology, and histology of 3D spheroids. As a result, ibuprofen and alcohol provoked synergistic hepatotoxicity against hepatocytes, and their toxicity increased prominently in 3D culture upon extended exposure. Oxidative stress appeared to be the mechanisms underlying the synergistic toxicity of ibuprofen and alcohol as evidenced by increased production of ROS and expression of the endogenous antioxidant system. Collectively, this study has demonstrated that ibuprofen and EtOH can induce synergistic hepatotoxicity, providing a line of evidence for caution against the use of ibuprofen in combination with alcohol.

Systematic review: ibuprofen-induced liver injury

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) are a leading cause of drug-induced liver injury (DILI) across the world. Ibuprofen is one of the most commonly used and safest NSAIDs, nevertheless reports on ibuprofen-induced hepatotoxicity are available.

AIM

To analyse previously published information on ibuprofen-induced liver injury for a better characterisation of its phenotypic expression.

METHOD

A systematic search was performed and information on ibuprofen-induced liver injury included in case series and case reports, in terms of demographic, clinical, biochemical and outcome data, was analysed.

RESULTS

Twenty-two idiosyncratic ibuprofen hepatotoxicity cases were identified in the literature, suggesting a very low prevalence of this type of DILI. These patients had a mean age of 31 years and 55% were females. Mean cumulative dose of ibuprofen and time to onset were 30 g and 12 days, respectively. Hepatocellular injury was the most frequently involved liver injury pattern. Six cases developed vanishing bile duct syndrome. Full recovery occurred in 11 patients after a mean time of 14 weeks, whereas five cases evolved to acute liver failure leading to death/liver transplantation.

CONCLUSIONS

When assessing potential hepatotoxicity cases, physicians should keep in mind that ibuprofen has been associated with hepatotoxicity in the literature. Ibuprofen-associated DILI presents commonly as hepatocellular damage after a short latency period. Published reports on ibuprofen hepatotoxicity leading to liver failure resulting in liver transplantation or death are available. However, due to the apparent low absolute risk of ibuprofen-induced liver complications, ibuprofen can be regarded as an efficacious and safe NSAID.

2018 Korean Liver Cancer Association-National Cancer Center Korea Practice Guidelines for the Management of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer globally and the fourth most common cancer in men in Korea, where the prevalence of chronic hepatitis B infection is high in middle-aged and elderly patients. These practice guidelines will provide useful and constructive advice for the clinical management of patients with HCC. A total of 44 experts in hepatology, oncology, surgery, radiology, and radiation oncology in the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2014 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions.

2018 Korean Liver Cancer Association-National Cancer Center Korea Practice Guidelines for the Management of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer globally and the fourth most common cancer in men in Korea, where the prevalence of chronic hepatitis B infection is high in middle-aged and elderly patients. These practice guidelines will provide useful and constructive advice for the clinical management of patients with HCC. A total of 44 experts in hepatology, oncology, surgery, radiology and radiation oncology in the Korean Liver Cancer Association-National Cancer Center Korea Practice Guideline Revision Committee revised the 2014 Korean guidelines and developed new recommendations that integrate the most up-to-date research findings and expert opinions.

Protective role of c-Jun N-terminal kinase-2 (JNK2) in ibuprofen-induced acute liver injury

Ibuprofen is a worldwide used non-steroidal anti-inflammatory drug which may cause acute liver injury (ALI) requiring liver transplantation. We aimed to unveil the molecular pathways involved in triggering ibuprofen-induced ALI, which, at present, remain elusive. First, we investigated activation of essential pathways in human liver sections of ibuprofen-induced ALI. Next, we assessed the cytotoxicity of ibuprofen in vitro and developed a novel murine model of ibuprofen intoxication. To assess the role of JNK, we used animals carrying constitutive deletion of c-Jun N-terminal kinase 1 (Jnk1^-/- ) or Jnk2 (Jnk2^-/- ) expression and included investigations using animals with hepatocyte-specific Jnk deletion either genetically (Jnk1^Δhepa ) or by siRNA (siJnk2^Δhepa ). We found in human and murine samples of ibuprofen-induced acute liver failure that JNK phosphorylation was increased in the cytoplasm of hepatocytes and other non-liver parenchymal cells (non-LPCs) compared with healthy tissue. In mice, ibuprofen intoxication resulted in a significantly stronger degree of liver injury compared with vehicle-treated controls as evidenced by serum transaminases, and hepatic histopathology. Next, we investigated molecular pathways. PKCα, AKT, JNK and RIPK1 were significantly increased 8 h after ibuprofen intoxication. Constitutive Jnk1^-/- and Jnk2^-/- deficient mice exhibited increased liver dysfunction compared to wild-type (WT) animals. Furthermore, siJnk2^Δhepa animals showed a dramatic increase in biochemical markers of liver function, which correlated with significantly higher serum liver enzymes and worsened liver histology, and MAPK activation compared to Jnk1^Δhepa or WT animals. In our study, cytoplasmic JNK activation in hepatocytes and other non-LPCs is a hallmark of human and murine ibuprofen-induced ALI. Functional in vivo analysis demonstrated a protective role of hepatocyte-specific Jnk2 during ibuprofen ALI. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Natural Dietary Pigments: Potential Mediators against Hepatic Damage Induced by Over-The-Counter Non-Steroidal Anti-Inflammatory and Analgesic Drugs

Over-the-counter (OTC) analgesics are among the most widely prescribed and purchased drugs around the world. Most analgesics, including non-steroidal anti-inflammatory drugs (NSAIDs) and acetaminophen, are metabolized in the liver. The hepatocytes are responsible for drug metabolism and detoxification. Cytochrome P450 enzymes are phase I enzymes expressed mainly in hepatocytes and they account for ≈75% of the metabolism of clinically used drugs and other xenobiotics. These metabolic reactions eliminate potentially toxic compounds but, paradoxically, also result in the generation of toxic or carcinogenic metabolites. Cumulative or overdoses of OTC analgesic drugs can induce acute liver failure (ALF) either directly or indirectly after their biotransformation. ALF is the result of massive death of hepatocytes induced by oxidative stress. There is an increased interest in the use of natural dietary products as nutritional supplements and/or medications to prevent or cure many diseases. The therapeutic activity of natural products may be associated with their antioxidant capacity, although additional mechanisms may also play a role (e.g., anti-inflammatory actions). Dietary antioxidants such as flavonoids, betalains and carotenoids play a preventive role against OTC analgesics-induced ALF. In this review, we will summarize the pathobiology of OTC analgesic-induced ALF and the use of natural pigments in its prevention and therapy.

Severe hepatitis arising from ipilimumab administration, following melanoma treatment with nivolumab

After 4 weeks of the last dose of nivolumab, a 59-year-old man with stage IV melanoma was subject to treatment with ipilimumab. After 5 weeks, the patient developed severe hepatitis, showing markedly elevated levels of both aspartate aminotransferase and alanine aminotransferase (>2000 U/l). Using pulse steroid therapy with 1000 mg/d of methylprednisolone, liver function initially improved, but then deteriorated upon dosage reduction. Subsequently, mycophenolate mofetil (MMF) was administered at a dose of 2 g/d in addition to the corticosteroid, which resulted in aspartate aminotransferase and alanine aminotransferase levels gradually improving to grade 1, and the corticosteroid dose was successfully reduced to 0.5 mg/kg/d of oral prednisolone. Liver function then remained stable when MMF was tapered. In conclusion, the use of MMF improved liver function in this patient with steroid-refractory hepatitis induced by immune checkpoint inhibitor administration.

Toxicant-Induced Hepatic Injury

The sudden failure of a previously healthy and functioning liver is a dramatic and devastating event. Acute liver failure is the common final pathway of a multitude of conditions and insults, all of which result in massive hepatic necrosis or loss of normal hepatic function. The ensuing multiorgan system failure frequently has a fatal outcome, with mortality rates in most series ranging from approximately 55% to 95% [1]. Acute liver failure (ALF, previously often referred to as fulminant hepatic failure (FHF)) knows no age boundaries, with many cases occurring in those younger than 30 years. Short of excellent intensive care unit (ICU) support and liver transplantation in selected cases, few viable treatment options are available. Over the past few decades, however, survival has been improved by anticipation, recognition, and early treatment of associated complications, as well as the application of prognostic criteria for early identification of patients requiring liver transplantation (along with improvement in the techniques and science of transplantation itself). The etiology of ALF varies from country to country and the incidence change over time. Paracetamol (acetaminophen) has now replaced viral hepatitis as the leading cause of ALF [2]. In a study from London including 310 patients with ALF in the period 1994–2004, 42% of the cases were caused by paracetamol [3], whereas this was only the cause in 2% of 267 patients in Spain from 1992 to 2000 [4]. However, less than 10% of all liver transplants are performed in patients with ALF [5, 6].

Drug-Induced Liver Injury: Pattern Recognition and Future Directions

Drug-induced liver injury (DILI) remains a significant clinical challenge and is the leading cause of acute liver failure in most countries. An aging population that uses more medications, a constant influx of newly developed drugs and a growing risk from unfamiliar herbal and dietary supplements will make DILI an increasing part of clinical practice. Currently, the most effective strategy for disease management is rapid identification, withholding the inciting agents, supportive care and having a firm understanding of the expected natural history. There are resources available to aid the clinician, including a new online "textbook" as well as causality assessment tools, but a heightened awareness of risk and the disease's varying phenotypes and good history-taking remain cornerstones to diagnosis. Looking ahead, growing registries of cases, pharmacoepidemiology studies and translational research into the mechanisms of injury may produce better diagnostic tools, markers for risk and disease, and prevention and therapeutics.

Immediate hypersensitivity reactions to ibuprofen and other arylpropionic acid derivatives

BACKGROUND

Although ibuprofen and other arylpropionic acid derivatives (APs) are the most common medicines involved in hypersensitivity drug reactions (HDRs) to NSAIDs, no patient series studies have been performed regarding immediate selective reactions (SRs) to these drugs.

OBJECTIVE

To characterize patients with immediate selective HDRs to ibuprofen and other APs through clinical history and challenge.

METHODS

Subjects who developed an HDR to APs less than 1 h after drug intake were included. Tolerance to aspirin was assessed and challenge was performed with ibuprofen in all cases, and additionally with the culprit drug (if different) in those patients that tolerated ibuprofen. Serum tryptase levels and tryptase immunohistochemical staining in skin biopsies were also assessed in some patients with a positive DPT to ibuprofen.

RESULTS

From a total of 245 patients with a confirmed history of HDRs to APs, 17% were classified as selective immediate hypersensitivity reactors by both clinical history and challenge. A selective response to naproxen and dexketoprofen with tolerance to ibuprofen was found in 16 of 20 cases. Significant differences in serum tryptase levels were observed between 2 and 24 h in the 11 cases that were studied further.

CONCLUSIONS

Within the group of patients with HDRs to NSAIDs, APs can induce immediate SRs. Within this group, selective responses to a single drug or responders to several APs may exist, suggesting potential immunological cross-reactivity.

Risk of acute and serious liver injury associated to nimesulide and other NSAIDs: data from drug-induced liver injury case-control study in Italy

Aim

Drug‐induced liver injury is one of the most serious adverse drug reactions and the most frequent reason for restriction of indications or withdrawal of drugs. Some nonsteroidal anti‐inflammatory drugs (NSAIDs) were withdrawn from the market because of serious hepatotoxicity. We estimated the risk of acute and serious liver injury associated with the use of nimesulide and other NSAIDs, with a prevalence of use greater than or equal to 5%.

Methods

This is a multicentre case–control study carried out in nine Italian hospitals from October 2010 to January 2014. Cases were adults, with a diagnosis of acute liver injury. Controls presented acute clinical disorders not related to chronic conditions, not involving the liver. Adjusted odds ratio (ORs) with 95% confidence interval (CI) were calculated initially with a bivariate and then multivariate analysis.

Results

We included 179 cases matched to 1770 controls. Adjusted OR for acute serious liver injury associated with all NSAIDs was 1.69, 95% CI 1.21–2.37. Thirty cases were exposed to nimesulide (adjusted OR 2.10, 95% CI 1.28–3.47); the risk increased according to the length of exposure (OR > 30 days: 12.55, 95% CI 1.73–90.88) and to higher doses (OR 10.69, 95% CI 4.02–28.44). Risk of hepatotoxicity was increased also for ibuprofen, used both at recommended dosages (OR 1.92, 95% CI 1.13–3.26) and at higher doses (OR 3.73, 95% CI 1.11–12.46) and for ketoprofen ≥ 150 mg (OR 4.65, 95% CI 1.33–10.00).

Conclusion

Among all NSAIDs, nimesulide is associated with the higher risk, ibuprofen and high doses of ketoprofen are also associated with a modestly increased risk of hepatotoxicity.

2014 KLCSG-NCC Korea Practice Guideline for the Management of Hepatocellular Carcinoma

The guideline for the management of hepatocellular carcinoma (HCC) was first developed in 2003 and revised in 2009 by the Korean Liver Cancer Study Group and the National Cancer Center, Korea. Since then, many studies on HCC have been carried out in Korea and other countries. In particular, a substantial body of knowledge has been accumulated on diagnosis, staging, and treatment specific to Asian characteristics, especially Koreans, prompting the proposal of new strategies. Accordingly, the new guideline presented herein was developed on the basis of recent evidence and expert opinions. The primary targets of this guideline are patients with suspicious or newly diagnosed HCC. This guideline provides recommendations for the initial treatment of patients with newly diagnosed HCC.

2014 Korean Liver Cancer Study Group-National Cancer Center Korea practice guideline for the management of hepatocellular carcinoma

The guideline for the management of hepatocellular carcinoma (HCC) was first developed in 2003 and revised in 2009 by the Korean Liver Cancer Study Group and the National Cancer Center, Korea. Since then, many studies on HCC have been carried out in Korea and other countries. In particular, a substantial body of knowledge has been accumulated on diagnosis, staging, and treatment specific to Asian characteristics, especially Koreans, prompting the proposal of new strategies. Accordingly, the new guideline presented herein was developed on the basis of recent evidence and expert opinions. The primary targets of this guideline are patients with suspicious or newly diagnosed HCC. This guideline provides recommendations for the initial treatment of patients with newly diagnosed HCC.

Nonsteroidal anti-inflammatory drug-induced hepatoxicity

Nonsteroidal anti-inflammatory drugs are among the most prescribed medications worldwide. After antibiotics and anticonvulsants they are considered the most common medications associated with drug-induced liver injury mainly through an idiosyncratic form of hepatotoxicity. In rare cases severe hepatotoxicity has been described with significant morbidity and mortality. Genetic risk factors have been reported with diclofenac and lumiracoxib. Postmarketing surveillance and monitoring is crucial to identify severe cases of hepatotoxicity.

High lipophilicity and high daily dose of oral medications are associated with significant risk for drug-induced liver injury

Drug-induced liver injury (DILI) is a leading cause of drug failure in clinical trials and a major reason for drug withdrawals from the market. Although there is evidence that dosages of ≥100 mg/day are associated with increased risk for hepatotoxicity, many drugs are safe at such dosages. There is an unmet need to predict risk for DILI more reliably, and lipophilicity might be a contributing factor. We analyzed the combined factors of daily dose and lipophilicity for 164 US Food and Drug Administration-approved oral medications and observed high risk for hepatotoxicity (odds ratio [OR], 14.05; P < 0.001) for drugs given at dosages ≥100 mg/day and octanol-water partition coefficient (logP) ≥3. This defined the "rule-of-two." Similar results were obtained for an independent set of 179 oral medications with 85% of the rule-of-two positives being associated with hepatotoxicity (OR, 3.89; P < 0.01). Using the World Health Organization's Anatomical Therapeutic Chemical classification system, the rule-of-two performed best in predicting DILI in seven therapeutic categories. Among 15 rule-of-two positives, 14 were withdrawn from hepatotoxic drugs, and one was over-the-counter medication labeled for liver injury. We additionally examined drug pairs that have similar chemical structures and act on the same molecular target but differ in their potential for DILI. Again, the rule-of-two predicted hepatotoxicity reliably. Finally, the rule-of-two was applied to clinical case studies to identify hepatotoxic drugs in complex comedication regimes to further demonstrate its use.

CONCLUSION

Apart from dose, lipophilicity contributes significantly to risk for hepatotoxicity. Applying the rule-of-two is an appropriate means of estimating risk for DILI compared with dose alone.

Review article: prescribing medications in patients with cirrhosis - a practical guide

BACKGROUND

Most drugs have not been well studied in cirrhosis; recommendations on safe use are based largely on experience and/or expert opinion, with dosing recommendations often based on pharmacokinetic (PK) changes.

AIM

To provide a practical approach to prescribing medications for cirrhotic patients.

METHODS

An indexed MEDLINE search was conducted using keywords cirrhosis, drug-induced liver injury, pharmacodynamics (PDs), PKs, drug disposition and adverse drug reactions. Unpublished information from the Food and Drug Administration and industry was also reviewed.

RESULTS

Most medications have not been adequately studied in cirrhosis, and specific prescribing information is often lacking. Lower doses are generally recommended based on PK changes, but data are limited in terms of correlating PD effects with the degree of liver impairment. Very few drugs have been documented to have their hepatotoxicity potential enhanced by cirrhosis; most of these involve antituberculosis or antiretroviral agents used for HIV or viral hepatitis. Paracetamol can be used safely when prescribed in relatively small doses (2-3 g or less/day) for short durations, and is recommended as first-line treatment of pain. In contrast, NSAIDs should be used cautiously (or not at all) in advanced cirrhosis. Proton pump inhibitors have been linked to an increased risk of spontaneous bacterial peritonitis (SBP) in cirrhosis and should be used with care.

CONCLUSIONS

Most drugs can be used safely in cirrhosis, including those that are potentially hepatotoxic, but lower doses or reduced dosing frequency is often recommended, due to altered PKs. Drugs that can precipitate renal failure, gastrointestinal bleeding, SBP and encephalopathy should be identified and avoided.

A rare coexistence: drug induced hepatitis and meningitis in association with Ibuprofen

Ibuprofen, a commonly used NSAID is reported to be associated with drug induced liver injury. Ibuprofen is also known to be associated with drug-induced meningitis especially in patients with connective tissue disorders. However presentation of hepatitis and meningitis in association with Ibuprofen use in the same individual has never been reported. We present a case of young woman who developed abnormal liver chemistries and neurological symptoms while on Ibuprofen. Her liver biopsy findings were suggestive of drug induced liver injury and cerebrospinal fluid analysis was suggestive of aseptic meningitis. Clinical and biochemical improvement was noted on cessation of Ibuprofen.

Phospho-ibuprofen (MDC-917) is a novel agent against colon cancer: efficacy, metabolism, and pharmacokinetics in mouse models

We have developed a novel chemical modification of conventional nonsteroidal anti-inflammatory drugs to reduce their toxicity and enhance their efficacy. Phospho-ibuprofen [(PI) 2-(4-isobutyl-phenyl)-propionic acid-4-(diethoxy-phosphoryloxy)-butyl ester (MDC-917)], a novel derivative of ibuprofen, strongly inhibited the growth of human colon cancer cells in vitro and SW480 human colon cancer xenografts in nude mice. PI was metabolized minimally by cultured cells, but extensively by liver microsomes and mice, undergoing regioselective oxidation to produce 1-OH-PI and carboxyl-PI, which can be hydrolyzed to 1-OH-ibuprofen and carboxyl-ibuprofen, respectively. PI also can be hydrolyzed to release ibuprofen, which can generate 2-OH-ibuprofen, carboxyl-ibuprofen, and ibuprofen glucuronide. After a single oral administration (400 mg/kg) of PI, ibuprofen and ibuprofen glucuronide are the main plasma metabolites of PI; they have, respectively, C(max) of 530 and 215 μM, T(max) of 1 and 2 h, elimination t(1/2) of 7.7 and 5.3 h, and area under the concentration-time curve (0-24 h) of 1816 and 832 μM × h. Intact PI was detected in several tissues but not in plasma; at a higher PI dose (1200 mg/kg), PI plasma levels were 12.4 μM. PI generated the same metabolites in mouse plasma as conventional ibuprofen, but with much lower levels, perhaps accounting for the enhanced safety of PI. The antitumor effect of PI was significantly associated with plasma ibuprofen levels (p = 0.016) but not with xenograft ibuprofen levels (p = 0.08), suggesting a complex anticancer effect. These results provide a pharmacological basis to explain, at least in part, the anticancer efficacy and safety of this promising compound and indicate that PI merits further evaluation as an anticancer agent.

Non-steroidal anti-inflammatory drugs: What is the actual risk of liver damage?

Non-steroidal anti-inflammatory drugs (NSAIDs) constitute a family of drugs, which taken as a group, represents one of the most frequently prescribed around the world. Thus, not surprisingly NSAIDs, along with anti-infectious agents, list on the top for causes of Drug-Induced Liver Injury (DILI). The incidence of liver disease induced by NSAIDs reported in clinical studies is fairly uniform ranging from 0.29/100 000 [95% confidence interval (CI): 0.17-051] to 9/100 000 (95% CI: 6-15). However, compared with these results, a higher risk of liver-related hospitalizations was reported (3-23 per 100 000 patients). NSAIDs exhibit a broad spectrum of liver damage ranging from asymptomatic, transient, hyper-transaminasemia to fulminant hepatic failure. However, under-reporting of asymptomatic, mild cases, as well as of those with transient liver-tests alteration, in conjunction with reports non-compliant with pharmacovigilance criteria to ascertain DILI and flawed epidemiological studies, jeopardize the chance to ascertain the actual risk of NSAIDs hepatotoxicity. Several NSAIDs, namely bromfenac, ibufenac and benoxaprofen, have been withdrawn from the market due to hepatotoxicity; others like nimesulide were never marketed in some countries and withdrawn in others. Indeed, the controversy concerning the actual risk of severe liver disease persists within NSAIDs research. The present work intends (1) to provide a critical analysis of the dissimilar results currently available in the literature concerning the epidemiology of NSAIDS hepatotoxicity; and (2) to review the risk of hepatotoxicity for each one of the most commonly employed compounds of the NSAIDs family, based on past and recently published data.

Over-the-counter analgesics in cirrhotic patients: a case-control study examining the risk of hospitalization for liver-associated events

OBJECTIVE

To assess the association between over-the-counter analgesic (OTCA) use and hospitalization for liver-associated events in cirrhotic patients.

MATERIAL AND METHODS

Ninety adult cirrhotics admitted with liver-associated events and 126 non-hospitalized cirrhotic controls were enrolled prospectively into a case-control study. Standardized questionnaires were used to obtain predictor variables, including detailed 30-day OTCA use. Data were analyzed via logistic regression.

RESULTS

Hepatitis C (43%), alcohol (34%), and cryptogenic (13%) were the most common etiologies of cirrhosis. OTCA use was similar between cases and controls in the 30 days prior to enrollment (34% vs. 44%; odds ratio, OR = 0.66, 95% confidence interval, CI = 0.37-1.16, p = 0.148). Adjusted analyses also found no significant association between OTCA use and hospitalization for liver-associated events (OR = 0.73, 95% CI = 0.38-1.38, p = 0.330). Furosemide (p = 0.001), lactulose (p = 0.026), and number of prior liver-associated events (p = 0.002) were positively associated with hospitalization, while propranolol showed an inverse association (p = 0.008).

CONCLUSION

Our data suggest that non-excessive OTCA use is not significantly associated with hospitalization for liver-associated events.

Ibuprofen-induced hypersensitivity syndrome

Ibuprofen is a widely used antipyretic and analgesic nonsteroidal antiinflammatory drug (NSAID). With the aging of the population, there will be a significant increase in the prevalence of painful degenerative and inflammatory rheumatic conditions. This increase likely will lead to a parallel increase in the use of NSAIDs, including ibuprofen. The primary effect of the NSAIDs is to inhibit cyclooxygenase (prostaglandin synthase), thereby impairing the ultimate transformation of arachidonic acid to prostaglandins, prostacyclin, and thromboxanes. Although in the majority of cases it is safe, this NSAID, ibuprofen, can produce an unpredictable, idiosyncratic, type B reaction that may pose a major concern in clinical practice. Type B reactions are known to occur in susceptible individuals. The true hypersensitivity reaction (HSR) is a systemic disease defined by the triad of fever, rash, and internal organ involvement that starts 1 day to 12 weeks after the initiation of therapy. HSR has limited the therapeutic use of many drugs, including ibuprofen. Hypersensitivity syndrome associated with ibuprofen is a host-dependent drug reaction that is idiosyncratic in nature. This reaction likely is caused by a combination of metabolic and immunologic factors. Immune mediated components, such as T-cell and their products cytokines and chemokines, can exacerbate cellular responses and create complex pathways that lead to a variety of clinical manifestations. Our review presents an ibuprofen-induced clinical manifestation of hypersensitivity syndrome and the necessity of wisely monitoring the patients clinically and by laboratory investigations when prescribing this drug.

Management of fever in children: summary of the Italian Pediatric Society guidelines

OBJECTIVE

This article summarizes the Italian Pediatric Society guideline on the management of the signs and symptoms of fever in children, prepared as part of the National Guideline Program (NGLP).

METHODS

Relevant publications in English and Italian were identified through searches of MEDLINE and the Cochrane Database of Systematic Reviews from their inception through December 31, 2007. Based on the consensus of a multidisciplinary expert panel, the strength of the recommendations was categorized into 5 grades (A-E) according to NGLP methodology.

SUMMARY

In the health care setting, axillary measurement of body temperature using a digital thermometer is recommended in children aged <4 weeks; for children aged > or =4 weeks, axillary measurement using a digital thermometer or tympanic measurement using an infrared thermometer is recommended. When body temperature is measured at home by parents or care-givers, axillary measurement using a digital thermometer is recommended for all children. Children who are afebrile when seen by the clinician but are reported to have had fever by their caregivers should be considered febrile. In special circumstances, high fever may be a predictive factor for severe bacterial infection. Use of physical methods of reducing fever is discouraged, except in the case of hyperthermia. Use of antipyretics-paracetamol (acetaminophen) or ibuprofen-is recommended only when fever is associated with discomfort. Combined or alternating use of antipyretics is discouraged. The dose of antipyretic should be based on the child's weight rather than age. Whenever possible, oral administration of paracetamol is preferable to rectal administration. Use of ibuprofen is not recommended in febrile children with chickenpox or dehydration. Use of ibuprofen or paracetamol is not contraindicated in febrile children with asthma. There is insufficient evidence to form any recommendations concerning fever in children with other chronic conditions, but caution is advised in cases of severe hepatic/renal failure or severe malnutrition. Newborns with fever should always be hospitalized because of the elevated risk of severe disease; paracetamol may be used, with the dose adjusted to gestational age. Use of paracetamol or ibuprofen is not effective in preventing febrile convulsion or the adverse effects of vaccines.

The hepatic safety and tolerability of the cyclooxygenase-2 selective NSAID celecoxib: pooled analysis of 41 randomized controlled trials

OBJECTIVE

To assess the hepatic safety and tolerability of celecoxib versus placebo and three commonly prescribed nonselective nonsteroidal anti-inflammatory drugs (NSAIDs).

RESEARCH DESIGN AND METHODS

This was a retrospective, pooled analysis of a 41-study dataset involving patients with osteoarthritis, rheumatoid arthritis, ankylosing spondylitis, chronic low back pain, and Alzheimer's disease. Criteria for selection of studies were: (1) Randomized, parallel-group design and planned treatment duration of > or =2 weeks (2) > or =1 placebo or NSAID comparator (3) > or =1 arm with celecoxib at total daily dose of > or =200 mg (4) Data available as of October 31, 2004 Data were pooled by treatment and subject from the safety analysis population of included studies. Treatment-emergent hepatobiliary adverse events (AEs) were compared for celecoxib <200 mg/day (943 patients), 200 mg/day (12 008 patients), 400 mg/day (7380 patients), and 800 mg/day (4602 patients); placebo (4057 patients); diclofenac 100-150 mg/day (7639 patients); naproxen 1000 mg/day (2953 patients); and ibuprofen 2400 mg/day (2484 patients). Hepatobiliary laboratory abnormalities were also analyzed.

RESULTS

There were no cases of liver failure, treatment-related liver transplant, or treatment-related hepatobiliary death. Incidence of serious hepatic AEs was low, with 13 (0.05%) serious hepatic AEs among 24 933 celecoxib-treated patients, and 16 (0.21%) among 7639 diclofenac-treated patients. No patients receiving celecoxib or any nonselective NSAID met criteria for Hy's rule (alanine aminotransferase [ALT] > or =3 x upper limit of normal [ULN] with bilirubin > or =2 x ULN). The incidence of notable (> or =5 x ULN) and severe (> or =10 x ULN) ALT elevations was similar for all treatment groups except diclofenac. Significantly fewer hepatobiliary AEs were reported for celecoxib (any dose; 1.11%) than for diclofenac (vs. 4.24%, p < 0.0001); for ibuprofen (vs. 1.53%, p = 0.06) and placebo (vs. 0.89%, p = 0.21) the incidence of AEs was comparable to celecoxib.

LIMITATIONS

A number of limitations should be considered when evaluating the results: findings were limited by the quality and reporting of the studies selected; difficulty in estimating the incidence of AEs due to the low frequency of events; acetaminophen not included as an active comparator.

CONCLUSIONS

In this pooled analysis, the incidence of hepatic AEs in patients treated with celecoxib was similar to that for both placebo-treated patients and patients treated with ibuprofen or naproxen, but lower than for diclofenac.

Review article: The use of potentially hepatotoxic drugs in patients with liver disease

BACKGROUND

Misconceptions surround the use of hepatotoxic drugs in chronic liver disease. While many prescription and over-the-counter (OTC) agents can be used safely, this often runs counter to labelled warnings/contraindications, especially for the statins and other commonly used agents.

AIM

To evaluate published data on the use of hepatotoxic drugs in chronic liver disease including pharmacokinetic changes in cirrhosis and drug interactions, where available, to formulate recommendations on their use.

METHODS

Using a combination of PubMed searches, review texts, the Physicians' Desk Reference and expert opinion, drugs considered at higher risk of hepatotoxicity in chronic liver disease were evaluated.

RESULTS

Most drugs and OTC products including herbals have not been formally studied in chronic liver disease, but available data suggest that several of the most commonly used agents, especially the statins, can be used safely. While there is an increased risk of drug-induced liver injury for drugs used in the treatment of tuberculosis and HIV patients with hepatitis B or C, recommendations for their safe use are emerging.

CONCLUSIONS

Although many clinicians remain hesitant to use hepatotoxic drugs in chronic liver disease, the database supporting this view is limited to just a few agents. Most medications can be used safely in patients with chronic liver disease with appropriate monitoring.

Nonsteroidal anti-inflammatory drug-induced hepatotoxicity

Nonsteroidal anti-inflammatory drugs are among the most common drugs associated with drug-induced liver injury, with an estimated incidence of between 3 and 23 per 100,000 patient years. Nimesulide, sulindac, and diclofenac seem to be associated with the highest risk and the only risk factor consistently identified is the concomitant use of other hepatotoxic drugs. Diclofenac-induced liver injury is a paradigm for drug-related hepatotoxicity. Recent studies suggest that genetic factors favoring the formation and accumulation of the reactive acylglucuronide metabolite of diclofenac and an enhanced immune response to the metabolite-protein adducts are associated with increased susceptibility to hepatotoxicity.

Diclofenac potassium 12.5mg tablets for mild to moderate pain and fever: a review of its pharmacology, clinical efficacy and safety

Non-prescription (over-the-counter [OTC]) analgesics are used for the short-term treatment of acute painful conditions of mild to moderate intensity in everyday life. Well documented safety and efficacy, a rapid onset of action and a flexible daily dosing regimen are essential in this context. Film-coated, immediate-release, low-dose diclofenac potassium, developed for OTC use, offers a flexible daily dosing regimen with an initial dose of two tablets (2 x 12.5mg) followed by one or two tablets up to a maximum daily dose of six tablets (75 mg/day). The maximum plasma drug concentration is reached 30 minutes after administration, and the mean terminal half-life is 1-2 hours, allowing a 4- to 6-hour duration of activity, depending on the condition. Thirteen randomised, double-blind trials with both placebo and active controls have demonstrated the efficacy of diclofenac potassium 12.5mg tablets in conditions suitable for treatment with OTC medication, for example, acute lower back pain, headache, acute pain after dental extraction, symptoms of cold and influenza (including fever), and dysmenorrhoea. A single dose of diclofenac potassium 12.5mg is the lowest recommended effective dose. A two-tablet single dose of 25mg is at least as effective as ibuprofen 400mg. A flexible dosing regimen of an initial two tablets followed by one or two tablets up to a total daily dose of 75 mg is as effective as ibuprofen used in comparable fashion up to a total daily dose of 1200 mg. The incidence of adverse events in patients taking single or multiple doses of diclofenac potassium is similar to that of ibuprofen and placebo. In a safety study conducted to compare diclofenac potassium with ibuprofen for up to 3 months in patients with osteoarthritis of the knee, no differences in the pattern of adverse events were noted. There was no evidence of either hepatic injury or cardiovascular safety-related issues at any time during the study. Patients are generally capable of taking diclofenac potassium appropriately. A maximum OTC treatment duration of 5 days for pain and 3 days for fever is recommended.

Idiosyncratic toxicity: a convergence of risk factors

The therapeutic margin for any drug is based on both toxicity and efficacy. Generally, toxicity is dose-dependent and is driven either by the therapeutic target or by an untoward target. However, idiosyncratic toxicities are usually not observed until a drug has been on the market and has gained broad exposure. Except in the case of pharmacokinetic interactions, these toxicities are not driven solely by drug exposure but rather depend on several drug- and patient-related risk factors. Drug-related risk factors include metabolism, bioactivation and covalent binding, and the inhibition of key cell functions. Patient-related risk factors include underlying disease, age, gender, comedications, nutritional status, activation of the innate immune system, physical activity, and genetic predispositions. Idiosyncratic toxicity can occur when a convergence of risk factors, including drug exposure, tips the risk-benefit balance away from benefit and toward risk.

Renal and liver transplantation for toxin-induced organ failure

OBJECTIVE

Determine the number and outcome of renal (January 1987-June 2001, inclusive) and liver transplants (January 1993-June 2001) performed in Ireland for drug or toxin-induced organ failure and identify the toxins involved.

METHODS

Retrospective review of national transplant coordinators' records and patient charts.

RESULTS

Fourteen patients received renal transplants for nephropathy secondary to drugs or toxins. In 12 of these cases, renal failure was attributed to chronic toxicity, principally cyclosporin A therapy (seven cases). One-year patient and graft survival were 100%. Twenty-nine liver transplants were for toxin-induced organ failure, and 20 of these were for chronic ethanol induced liver disease. One-year patient and graft survival rates were 77% and 73%, respectively.

CONCLUSIONS

Kidney and liver transplants were needed more often because of chronic toxicity than acute poisoning. Both groups had good outcomes at one year post-transplantation.

Hepatitis C and arthritis: an update

Extrahepatic symptoms during chronic hepatitis C virus (HCV) infection are common and varied. Arthritis can be seen either as part of autoimmune processes (eg, associated with cryoglobulinemia) or independently. Whether the manifestation is specifically attributable to HCV infection or rather to the nonspecific result of a chronic inflammatory process is not clear. The literature available at this time is insufficient to guide the most appropriate course of treatment of HCV arthritis. Standard antirheumatic treatment can be considered, but with caution, because some of these medications occasionally may be hepatotoxic and response to therapy seems variable. Treatment decisions should be determined on a case-by-case basis.

Outpatient Management of Cirrhosis: A Narrative Review

Cirrhosis is the 12th leading cause of death in the United States. Individuals with cirrhosis are at risk for many potential complications. Complications can be managed or detected early with proper outpatient management. The most lethal of these complications is bleeding esophageal varices. All patients with cirrhosis should be screened for the presence of varices and treated when indicated. The most common complication seen in these patients is ascites. Ascites can be treated with dietary modifications and a diuretic regimen. Other potential complications include spontaneous bacterial peritonitis, hepatocellular carcinoma, hepatic encephalopathy, hepatorenal syndrome, and hepatopulmonary syndrome. The outpatient management of these complications will be discussed in this paper, along with the use of vaccinations, educating patients about the avoidance of hepatotoxic drugs, and when to refer a patient for liver transplant.

Causality assessment in drug-induced hepatotoxicity

Drugs are currently an important cause of liver disease, ranked as the most frequent reason for acute liver failure. Despite recent advances in knowledge of the mechanisms implicated in drug-induced hepatocellular damage and cholestasis, as well as the identification of several risk factors, the diagnosis of hepatotoxicity remains a difficult task because specific tests are not available. In a step-by-step approach, the incrimination of a drug in liver symptoms requires a high degree of suspicion on the part of the physician, temporal eligibility, awareness of the drug's hepatotoxic potential, the exclusion of alternative causes of liver damage, and the ability to detect the presence of subtle data that favour a toxic aetiology. Ultimately, the use of diagnostic algorithms may add consistency to the diagnostic process either by translating the suspicion into a quantitative score or by providing a framework that emphasises the features that merit attention in cases of suspected hepatic adverse reactions.

Subliminal Fas stimulation increases the hepatotoxicity of acetaminophen and bromobenzene in mice

The hepatotoxicity of several drugs is increased by mild viral infections. During such infections, death receptor ligands are expressed at low levels, and most parenchymal cells survive. We tested the hypothesis that subliminal death receptor stimulation may aggravate the hepatotoxicity of drugs, which are transformed by cytochrome P-450 cytochrome P-450 into glutathione-depleting reactive metabolites. Twenty-four-hour-fasted mice were pretreated with a subtoxic dose of the agonistic Jo2 anti-Fas antibody (1 microg per mouse) 3 hours before acetaminophen (500 mg/kg) or 1 hour before bromobenzene (400 mg/kg) administration. Administration of Jo2 alone increased hepatic inducible nitric oxide synthase nitric oxide synthase but did not modify serum alanine aminotransferase (ALT), hepatic adenosine triphosphate (ATP), glutathione (GSH), cytochrome P-450, cytosolic cytochrome c, caspase-3 activity or hepatic morphology. However, pretreating mice with Jo2 further decreased both hepatic GSH and ATP by 40% 4 hours after acetaminophen administration, and further increased serum ALT and the area of centrilobular necrosis at 24 hours. In mice pretreated with the Jo2 antibody before bromobenzene administration, hepatic GSH 4 hours after bromobenzene administration was 51% lower than in mice treated with bromobenzene alone, and serum ALT activity at 24 hours was 47-fold higher. In conclusion, administration of a subtoxic dose of an agonistic anti-Fas antibody before acetaminophen or bromobenzene increases metabolite-mediated GSH depletion and hepatotoxicity. Subliminal death receptor stimulation may be one mechanism whereby mild viral infections can increase drug-induced toxicity.

Hepatocellular damage from non-steroidal anti-inflammatory drugs

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for the management of rheumatological disorders, and as analgesics and antipyretics. Hepatotoxicity is an uncommon, but potentially lethal complication, which usually occurs within 12 weeks of starting therapy. It can occur with all NSAIDs, but appears to be more common with diclofenac and particularly sulindac. Female patients aged >50 years, with autoimmune disease, and those on other potentially hepatotoxic drugs, appear to be particularly susceptible. Liver function test abnormalities generally settle within 4-6 weeks of stopping the causative drug. However, some patients may develop acute liver failure and successful orthotopic liver transplantation may be undertaken in such patients. Recent in vitro animal studies have shown that the mechanism of diclofenac toxicity relates both to impairment of ATP synthesis by mitochondria, and to production of active metabolites, particularly n,5-dihydroxydiclofenac, which causes direct cytotoxicity. Mitochondrial permeability transition (MPT) has also been shown to be important in diclofenac-induced liver injury, resulting in generation of reactive oxygen species, mitochondrial swelling and oxidation of NADP and protein thiols. Physicians and hepatologists must be vigilant to the hepatotoxic potential of any NSAID, as increased awareness, surveillance and reporting of these events will lead to a better understanding of the risk factors and the pathophysiology of NSAID-related hepatotoxicity.

Animal models of human disease in drug safety assessment

Animal models of human disease have been widely used in drug discovery, but they are rarely utilized in toxicological research and screening (except for transgenic models in carcinogenicity testing). Although genetic and/or acquired pathophysiological alterations associated with a particular disease may greatly exacerbate toxic responses to drugs in certain patient subsets, these pre-existing pathological conditions are usually not considered in preclinical safety assessment. Examples of disease-related determinants of susceptibility include disruption of the cytokine network in pro-inflammatory conditions, mitochondrial alterations and oxidative stress in certain neurodegenerative diseases, altered antioxidant defense in certain viral infections, and altered gene expression and mitochondrial dysfunction in type 2 diabetes. Hence, if cellular stress caused by drugs or metabolites and the disease-related effects are superimposed, then an individual can become sensitized to potential drug toxicity. Animal models of modest inflammation indeed can potentiate the toxicity of certain drugs. Similarly, rodent models of type 2 diabetes predispose the animals to hepatotoxic effects of thiazolidinediones antidiabetics. In conclusion, it is suggested that tailor-made and simplified models be adopted and increasingly used, in spite of clear limitations, as optimal substrates for satellite toxicity studies to facilitate candidate selection, help predict rare and unexpected toxicity, and identify new biomarkers.

Hepatotoxicity associated with non-steroidal anti-inflammatory drugs

NSAIDs are one of most frequently prescribed agents in clinical practice. Whereas hepatotoxicity is a rare complication of most NSAIDs (typically 1 to 10 per 100,000 persons exposed), the high level of usage means that these drugs cause liver disease. Because of their divergent chemical structures, the mechanisms and clinicopathological manifestations of hepatotoxicity vary widely. The reactive metabolite syndrome, in which serious rash, eosinophilia, and other forms of tissue injury are common, may be incited by several NSAIDs, including newer agents. Women, people aged more than 50 years, and for some drugs, the type of arthritis, may be risk factors for drug-induced liver injury. The spectrum of NSAID-drug related hepatotoxicity continues to expand, with reports of interactive toxicity in adults with hepatitis C and recognition of rare cases of liver disease associated with non-selective, selective, and preferential COX-2 inhibitors. Better outcomes require people taking NSAIDs to be aware of possible drug reactions involving the liver, and prescribers should be vigilant for early symptoms of hepatotoxicity so that incriminated agents are discontinued promptly.

The rational use of potentially hepatotoxic medications in patients with underlying liver disease

Given the fact that as many as 9% of all adverse drug reactions involve toxic effects on the liver and with upwards of 50% of all cases of fulminant hepatic failure being ascribed to acetaminophen and other agents, the safe use of medications takes on an even greater importance whenever the prescription of potentially hepatotoxic drugs to patients with underlying liver disease is considered. In general, it is thought that most drugs can be safely administered in the setting of liver disease without an increased risk of hepatotoxicity, although the evidence on which this statement is based often relies more on clinical judgement than on clinical studies. Several drugs appear to have an increased risk of hepatotoxicity in patients with underlying liver disease based on either clinical reports or extrapolated pharmacological data. These agents, including methotrexate, niacin and the antiretroviral and antituberculosis drugs, carry warnings about their use in patients with a variety of liver conditions. The data supporting the hepatotoxic risk of scores of additional drugs, such as the 3-Hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors ("statins"), the newer thiazolidinediones (rosiglitazone, pioglitazone), and tamoxifen, among others, in patients with liver disease are generally lacking by evidence-based studies. However, clinical and biochemical monitoring is routinely recommended or required, often to make up for the lack of information on the true risk of clinically significant liver toxicity of these agents in individuals both with and without underlying liver disease. This article will review what is and what is not known about prescribing in the setting of acute and chronic liver disease and offers recommendations to help promote the safe and rational use of potentially hepatotoxic medications in these patients.

Metabolic, idiosyncratic toxicity of drugs: overview of the hepatic toxicity induced by the anxiolytic, panadiplon

Preclinical drug safety evaluation studies, typically conducted in two or more animal species, reveal and define dose-dependent toxicities and undesirable effects related to pharmacological mechanism of action. Idiosyncratic toxic responses are often not detected during this phase in development due to their relative rarity in incidence and differences in species sensitivity. This paper reviews and discusses the metabolic idiosyncratic toxicity and species differences observed for the experimental non-benzodiazepine anxiolytic, panadiplon. This compound produced evidence of hepatic toxicity in Phase 1 clinical trial volunteers that was not predicted by rat, dog or monkey preclinical studies. However, subsequent studies in Dutch-belted rabbits revealed a hepatic toxic syndrome consistent with a Reye's Syndrome-like idiosyncratic response. Investigations into the mechanism of toxicity using rabbits and cultured hepatocytes from several species, including human, provided a sketch of the complex pathway required to produce hepatic injury. This pathway includes drug metabolism to a carboxylic acid metabolite (cyclopropane carboxylic acid), inhibition of mitochondrial fatty acid beta-oxidation, and effects on intermediary metabolism including depletion of glycogen and disruption of glucose homeostasis. We also provide evidence suggesting that the carboxylic acid metabolite decreases the availability of liver CoA and carnitine secondary to the formation of unusual acyl derivatives. Hepatic toxicity could be ameliorated by administration of carnitine, and to a lesser extent by pantothenate. These hepatocellular pathway defects, though not directly resulting in cell death, rendered hepatocytes sensitive to secondary stress, which subsequently produced apoptosis and hepatocellular necrosis. Not all rabbits showed evidence of hepatic toxicity, suggesting that individual or species differences in any step along this pathway may account for idiosyncratic responses. These differences may be roughly applied to other metabolic idiosyncratic hepatotoxic responses and include variations in drug metabolism, effects on mitochondrial function, nutritional status, and health or underlying disease.

Drug-induced liver disease

This year's review is divided into several sections: the first describes drug withdrawals and new general reviews of drug-induced liver disease (DILD), including a review of a classification of drug injury. We review agents newly described as causing DILD, and new reports of DILD from established agents appearing in the year 2000. New aspects regarding the treatment of acetaminophen toxicity are included, and in the final section we deal with prevention of DILD as well as issues surrounding the use of potentially hepatotoxic medications in patients with underlying chronic disease.

Rheumatic disorders associated with hepatitis C

The hepatitis C virus (HCV) is a common virus of world-wide distribution affecting up to 3% of the world's population. Its genetic diversity, with multiple subtypes, and existence in the form of quasispecies in individual hosts, is, in part, responsible for high rates of chronic infection. Individuals with HCV infection will undoubtedly present to rheumatologists and other health care professionals with rheumatic and other immunological disorders related to what was usually a remote and asymptomatic acute infection. The goals of this review are: (1) to summarize clinical observations regarding rheumatological and immunological diseases linked with HCV infection; (2) to provide relevant information on the molecular biology of HCV; (3) to discuss the state of the art regarding the use of diagnostic studies; (4) to consider the differential diagnosis of liver disease and rheumatic disorders; and (5) to provide a practical guide to the history, physical examination, laboratory work-up, disease monitoring, and therapy of HCV patients with rheumatic disorders.

Drug-induced liver disease

The incidence of drug-induced liver disease appears to be increasing, reflecting the increasing number of new agents that have been introduced into clinical use over the past several decades. Among the topics covered, the author discusses incidence, diagnosis, risk factors, clinical presentations, hepatitis, and vascular injury. The author also reviews the hepatic injury seen with commonly prescribed drugs, emphasizing newer developments in the field and recent publications and reports.

Interferon-alpha 2b combined with daily ketoprofen administration improves virological response in chronic hepatitis C: a prospective and randomised trial

BACKGROUND

Less than 15% of patients with chronic hepatitis C show a sustained virological response to interferon treatment.

AIM

To evaluate the efficacy and safety of different doses of ketoprofen combined with interferon-alpha 2b in the treatment of chronic hepatitis C.

PATIENTS/METHODS

Seventy compensated patients with chronic hepatitis C received interferon-alpha 2b 3 million units three times a week for six months. They were randomly assigned to: group 1 (n = 23), interferon-alpha 2b alone; group 2 (n = 23), interferon-alpha 2b plus 200 mg ketoprofen three times a week; group 3 (n = 24), interferon-alpha 2b plus 200 mg ketoprofen twice a day. Complete and sustained responses were defined as normal serum alanine aminotransferase levels and negative serum hepatitis C virus RNA at six and 12 months respectively.

RESULTS

Complete and sustained responses were similar in groups 1 and 2: 10% v 5% and 5% v 0% respectively. In group 3, complete response was 29% (p = 0.13 v group 1 and p = 0.04 v group 2) and sustained response was 26% (p = 0.07 v group 1 and p = 0.01 v group 2). Overall, adverse events were similar in the three groups. However, 'flu-like syndrome was less common in group 2 (30%) and group 3 (37%) than in group 1 (77%) (p = 0.01).

CONCLUSIONS

Twice daily ketoprofen administration combined with interferon-alpha 2b produced an increase in complete and sustained responses. Although the combination of interferon-alpha 2b with ketoprofen was well tolerated and decreased the incidence of 'flu-like syndrome, it is advisable to monitor possible non-steroid anti-inflammatory drug hepatotoxicity.

Pathologic features of chronic hepatitis. A review and update

The general histopathologic changes of chronic hepatitis and those related to the various causes are reviewed. Consideration also is given to underlying or associated diseases and to mixed infections in chronic viral hepatitis. Changes occurring in exacerbations or relapses are described. Selected histopathologic changes are illustrated. The nomenclature is reviewed briefly, with emphasis on separation of activity from stage of disease.