Drug-induced hepatic injury

A prospective observational study to evaluate Glutathione S-transferase gene polymorphism and its association with Antitubercular drugs induced liver injury in tertiary hospital

BACKGROUND

Anti-TB drugs are most common cause of idiosyncratic hepatotoxicity worldwide. Reactive metabolite formed during drug metabolism has been involved in a clinical toxicity are described as 'idiosyncratic' drug induce liver injury (DILI). We have observed the distribution of glutathione S -transferase (GST) gene polymorphism & its association with drug-induced liver injury in patients taking anti-tubercular treatment.

METHODS

A prospective observational study including 96 patients receiving anti-tubercular treatment. Blood sample was collected for LFT and gene extraction after ruling out other cause of liver injury. DNA extraction for GST gene was done follow by polymerase chain reaction to identify homozygous null mutation at GSTM1 and GSTT1 loci. Association of GSTM1 and GSTT1 gene with DILI was seen.

RESULTS

Out of 96 tubercular patients under treatment, drug induced liver injury was found in 21 (21.9%) patients and 75 does not develop DILI, GST M1 gene null mutation was observed in 14 (66.7%), GST T1 gene null mutation was observed in 9 (42.9%), Both GST gene null mutation was observed in 8 (38.1%) in DILI group.

CONCLUSION

The GSTM1 gene null mutation and both GSTM1 and T1 gene null mutation were a risk factor for the development of DILI. But there is no significant association between GSTT1 gene null mutation and DILI in TB patients.

Pre-clinical 2D and 3D toxicity response to a panel of nanomaterials; comparative assessment of NBM-induced liver toxicity

Nanobiomaterials, or NBMs, have been used in medicine and bioimaging for decades, with wide-reaching applications ranging from their uses as carriers of genes and drugs, to acting as sensors and probes. When developing nanomedicine products, it is vitally important to evaluate their safety, ensuring that both biocompatibility and efficacy are achieved so their applications in these areas can be safe and effective. When discussing the safety of nanomedicine in general terms, it is foolish to make generalised statements due to the vast array of different manufactured nanomaterials, formulated from a multitude of different materials, in many shapes and sizes; therefore, NBM pre-clinical screening can be a significant challenge. Outside of their distribution in the various tissues, organs and cells in the body, a key area of interest is the impact of NBMs on the liver. A considerable issue for researchers today is accurately predicting human-specific liver toxicity prior to clinical trials, with hepatotoxicity not only the most cited reasons for withdrawal of approved drugs, but also a primary cause of attrition in pre-launched drug candidates. To date, no simple solution to adequately predict these adverse effects exists prior to entering human experimentation. The limitations of the current pre-clinical toolkit are believed to be one of the main reasons for this, with questions being raised on the relevance of animal models in pre-clinical assessment, and over the ability of conventional, simplified in vitro cell–based assays to adequately assess new drug candidates or NBMs. Common 2D cell cultures are unable to adequately represent the functions of 3D tissues and their complex cell–cell and cell–matrix interactions, as well as differences found in diffusion and transport conditions. Therefore, testing NBM toxicity in conventional 2D models may not be an accurate reflection of the actual toxicity these materials impart on the body. One such method of overcoming these issues is the use of 3D cultures, such as cell spheroids, to more accurately assess NBM-tissue interaction. In this study, we introduce a 3D hepatocellular carcinoma model cultured from HepG2 cells to assess both the cytotoxicity and viability observed following treatment with a variety of NBMs, namely a nanostructured lipid carrier (in the specific technical name = LipImage^™ 815), a gold nanoparticle (AuNP) and a panel of polymeric (in the specific technical name = PACA) NBMs. This model is also in compliance with the 3Rs policy of reduction, refinement and replacement in animal experimentation [1], and meets the critical need for more advanced in vitro models for pre-clinical nanotoxicity assessment.

The Garcinia kola biflavonoid kolaviron attenuates experimental hepatotoxicity induced by diclofenac

This study sought to investigate the effects of kolaviron on diclofenac-induced hepatotoxicity in rats. Sixty male Wistar rats were divided into 6 groups of 10 rats each as follows: a control group that received oral propylene glycol and treatment groups that received diclofenac alone, diclofenac followed by Livolin Forte (a reference drug), or diclofenac followed by kolaviron at three different doses. At the end of the study period, five rats per group were sacrificed under ketamine hydrochloride anesthetic, 24h after treatment, while the other 5 rats in the group were allowed to recover for 2 weeks before being sacrificed. Liver enzyme activities, total bilirubin levels, and the concentrations of several pro-inflammatory cytokines were determined using plasma samples, while liver tissue samples were used for antioxidant analysis and histopathological examination. Compared with the control group, plasma liver enzyme activities, along with bilirubin levels, were higher in the groups that received diclofenac alone or diclofenac+the highest dose of kolaviron, respectively. These groups had higher plasma concentrations of pro-inflammatory cytokines than did the control group. However, the administration of Livolin Forte and kolaviron (at the lower doses) ameliorated diclofenac-induced hepatic injury by improving antioxidant status, preventing an increase in inflammatory mediators, decreasing malondialdehyde, and attenuating the adverse effect of diclofenac on hepatic tissues. In addition, there was a significant difference in the histological scores between the groups that received either diclofenac alone or diclofenac followed by the highest dose of kolaviron when compared with the other three groups (Livolin Forte or lower doses of kolaviron). In conclusion, kolaviron appears to be as effective as Livolin in attenuating DCLF-induced hepatotoxicity in rats. However, high doses of kolaviron seem to cause damage to the liver.

Beware: Antibiotic-Induced Hepatotoxicity is Rare but Deadly

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Role of nonalcoholic fatty liver disease as risk factor for drug-induced hepatotoxicity

BACKGROUND

Obesity is often associated with nonalcoholic fatty liver disease (NAFLD), which refers to a large spectrum of hepatic lesions including fatty liver, nonalcoholic steatohepatitis (NASH) and cirrhosis. Different investigations showed or suggested that obesity and NAFLD are able to increase the risk of hepatotoxicity of different drugs. Some of these drugs could induce more frequently an acute hepatitis in obese individuals whereas others could worsen pre-existing NAFLD.

AIM

The main objective of the present review was to collect the available information regarding the role of NAFLD as risk factor for drug-induced hepatotoxicity. For this purpose, we performed a data-mining analysis using different queries including drug-induced liver injury (or DILI), drug-induced hepatotoxicity, fatty liver, nonalcoholic fatty liver disease (or NAFLD), steatosis and obesity. The main data from the collected articles are reported in this review and when available, some pathophysiological hypotheses are put forward.

RELEVANCE FOR PATIENTS

Drugs that could pose a potential risk in obese patients include compounds belonging to different pharmacological classes such as acetaminophen, halothane, methotrexate, rosiglitazone, stavudine and tamoxifen. For some of these drugs, experimental investigations in obese rodents confirmed the clinical observations and unveiled different pathophysiological mechanisms which could explain why these pharmaceuticals are particularly hepatotoxic in obesity and NAFLD. Other drugs such as pentoxifylline, phenobarbital and omeprazole might also pose a risk but more investigations are required to determine whether this risk is significant or not. Because obese people often take several drugs for the treatment of different obesity-related diseases such as type 2 diabetes, hyperlipidemia and coronary heart disease, it is urgent to identify the main pharmaceuticals that can cause acute hepatitis on a fatty liver background or induce NAFLD worsening.

A cross-sectional investigation of chronic exposure to microcystin in relationship to childhood liver damage in the Three Gorges Reservoir Region, China

BACKGROUND

Microcystin-producing Microcystis bloom is a severe water problem in the world. Some reports indicate that chronic exposure to microcystin may result in liver damage in adults, but information on effects in children is limited.

OBJECTIVE

We investigated the relationship between microcystin exposure and liver damage in children.

METHODS

We measured microcystin concentrations in drinking water and aquatic food (carp and duck) from two lakes and four wells. Participants were 1,322 children 7-15 years of age who obtained drinking water from one of the tested sources, completed questionnaires, and provided blood samples for serum liver enzymes [alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and γ-glutamyltransferase (GGT)] and serum microcystin analysis. Multivariable logistic regression was used to identify risk factors associated with liver damage (two or more abnormal serum enzyme levels in ALT, AST, ALP, or GGT).

RESULTS

Microcystin was detected in most samples of water and aquatic food from two lakes. Children who drank water from the lake with the highest microcystin concentrations had a total estimated daily microcystin intake of 2.03 μg, a value much higher than the tolerable daily intake (0.40 μg) proposed by the World Health Organization for children. Hepatitis B virus (HBV) infection, use of hepatotoxic medicines, and microcystin exposure were associated with liver damage. AST and ALP levels were significantly higher in high-microcystin-exposed children than in low-exposed children and unexposed children when participants who were HBV-positive or hepatotoxic medicine users were excluded from the analysis.

CONCLUSION

These results suggest that chronic exposure to microcystin may be associated with liver damage in children in the Three Gorges Reservoir Region.

Clinical features of autoimmune hepatitis diagnosed based on simplified criteria of the International Autoimmune Hepatitis Group

BACKGROUND

Recently, simplified diagnostic criteria for autoimmune hepatitis have been proposed.

AIM

We aimed to evaluate usefulness of the simplified criteria.

METHODS

We applied the simplified criteria to 176 autoimmune hepatitis patients diagnosed according to the revised scoring system proposed in 1999 (original criteria). Furthermore, in order to compare predictabilities between these two diagnostic criteria, we included 168 patients with other liver disease than autoimmune hepatitis.

RESULTS

Of 176 autoimmune hepatitis patients, 85% were diagnosed with autoimmune hepatitis according to the simplified criteria, and patients diagnosed according to the simplified criteria showed a higher frequency of antinuclear antibodies and/or smooth muscle antibodies of 1:80 or greater and slightly higher serum levels of immunoglobulin G than those diagnosed according to the original criteria. However, 30% of male patients, 23% of patients with acute presentation, 50% of patients showing histological acute hepatitis and 46% of patients negative for antinuclear antibodies at presentation were not diagnosed with autoimmune hepatitis according to the simplified criteria. The simplified criteria showed lower sensitivity (85% vs. 100%) and higher specificity (99% vs. 93%) for autoimmune hepatitis than the original criteria.

CONCLUSIONS

The simplified criteria may be useless for the diagnosis of patients with atypical features, especially patients with histological acute hepatitis.

Effect of tetracycline on pancreas and liver function of adult male albino rats

The effect of tetracycline, at two doses of 50 and 200 mg kg−1 daily, was studied on pancreatic and liver tissue function for 14 and 21 days in adult male albino rats. For pancreatic function the parameters studied were content of amylase and lipase in pancreas, serum amylase and lipase, serum glucose and faecal fat excretion. For liver function, liver specific enzymes in serum, namely alanine amino transaminase, aspartate amino transaminase and lactate dehydrogenase were estimated. In addition, total lipid, antiperoxidative enzymes and lipid peroxidation were measured in pancreas and liver. The content of amylase and lipase in pancreas showed a small but significant decrease in the rats given 50 mg kg−1 for 21 days and the decrease was much more significant in those receiving the 200 mg kg−1 dose. In pancreas free radical levels show a significant increase and reduced glutathione shows a substantial decrease at the 50 mg kg−1 level and a significant change in these parameters was observed at the 200 mg kg−1 dose. Antioxidant enzymes, superoxide dismutase, glutathione peroxidase, glutathione reductase and catalase, showed a small but significant decrease in the pancreas of the rats treated with 50 mg kg−1 tetracycline. A significant decrease in the antioxidant enzymes level was observed at the 200 mg kg−1 dose. In the liver, free radical levels and reduced glutathione were within the normal range at the 50 mg kg−1 level and significant changes were observed at 200 mg kg−1. The antioxidant status was unaffected in liver after treatment with tetracycline at the 50 mg kg−1 level and a significant decrease was observed at the higher dose. Our results reveal the safe nature of tetracycline with respect to the liver at the lower dose tested, whereas, both the higher and lower doses seem to have detrimental effect on the pancreas as revealed by the rise in free radical levels and decrease in the antioxidant enzyme levels.

Rifampicin-activated human pregnane X receptor and CYP3A4 induction enhance acetaminophen-induced toxicity

Acetaminophen (APAP) is safe at therapeutic levels but causes hepatotoxicity via N-acetyl-p-benzoquinone imine-induced oxidative stress upon overdose. To determine the effect of human (h) pregnane X receptor (PXR) activation and CYP3A4 induction on APAP-induced hepatotoxicity, mice humanized for PXR and CYP3A4 (TgCYP3A4/hPXR) were treated with APAP and rifampicin. Human PXR activation and CYP3A4 induction enhanced APAP-induced hepatotoxicity as revealed by hepatic alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities elevated in serum, and hepatic necrosis after coadministration of rifampicin and APAP, compared with APAP administration alone. In contrast, hPXR mice, wild-type mice, and Pxr-null mice exhibited significantly lower ALT/AST levels compared with TgCYP3A4/hPXR mice after APAP administration. Toxicity was coincident with depletion of hepatic glutathione and increased production of hydrogen peroxide, suggesting increased oxidative stress upon hPXR activation. Moreover, mRNA analysis demonstrated that CYP3A4 and other PXR target genes were significantly induced by rifampicin treatment. Urinary metabolomic analysis indicated that cysteine-APAP and its metabolite S-(5-acetylamino-2-hydroxyphenyl)mercaptopyruvic acid were the major contributors to the toxic phenotype. Quantification of plasma APAP metabolites indicated that the APAP dimer formed coincident with increased oxidative stress. In addition, serum metabolomics revealed reduction of lysophosphatidylcholine in the APAP-treated groups. These findings demonstrated that human PXR is involved in regulation of APAP-induced toxicity through CYP3A4-mediated hepatic metabolism of APAP in the presence of PXR ligands.

The role of hepatitis E virus testing in drug-induced liver injury

BACKGROUND

Locally acquired hepatitis E is an emerging infection in developed countries and can be misdiagnosed as drug-induced liver injury.

AIM

To study the role of hepatitis E virus (HEV) testing in drug-induced liver injury.

METHODS

Retrospective review of a cohort of patients with suspected drug-induced liver injury (n = 69) and hepatitis E (n = 45). The standard criteria for drug-induced liver injury were applied. Patients with suspected drug-induced liver injury who met these criteria were retrospectively tested for HEV on stored sera taken at the time of presentation. The two cohorts were compared to determine variables that predicted either of the diagnoses.

RESULTS

Forty-seven out of 69 patients had criterion-referenced drug-induced liver injury. 22/47 were HEV negative and thus had confirmed drug-induced liver injury. 19/47 were not tested for HEV, as there was no sera available from the time of presentation. 6/47 were HEV positive and thus did not have drug-induced liver injury, but had hepatitis E infection. Compared to patients with confirmed drug-induced liver injury, patients with hepatitis E were significantly more likely to be male (OR 3.09, CI 1.05-9.08); less likely to present in November and December (0.03, CI 0.01-0.52); have lower serum bilirubin (P = 0.015); and higher serum alanine aminotransferase (P < 0.001) and alanine aminotransferase/alkaline phosphatase ratio (P < 0.001).

CONCLUSION

The diagnosis of drug-induced liver injury is not secure without testing for HEV.

From the bench to the clinic and back again: translational biomarker discovery using in silico mining of pharmacogenomic data

To improve drug efficacy and safety and advance medical intervention in diseases, new biomarkers are urgently needed. Pharmacogenomics can provide a tool to discover and begin to qualify biomarkers useful for these indications and is readily applicable to multiple species. One can begin and end with genes or focus on tissue-derived expression analysis of those genes that encode secreted proteins to discover potential biomarkers that can be monitored in body fluids. The paper will discuss issues surrounding such investigations, show examples of translational biomarkers and end with a summary of the US FDA’s work in this field over the last 6 years.

Drug-induced splenic enlargement

Splenomegaly results from different abnormal conditions susceptible to drugs. Their diagnosis is based on a history of exposure to a drug before the spleen enlargement. This paper reviews studies on drugs that may induce to splenomegaly. Drugs may provoke the enlargement of the spleen by direct effect on splenic cells or as a side effect of disturbances in other organs, such as the liver, or systems, such as the haematoimmunological system. Some drugs provoke severe haemolysis associated with splenomegaly. Another cause of spleen increasing in size is the venous congestion due to liver disturbance with portal vein occlusion as side complications of drugs. All these drug side effects are usually transitory and splenomegaly disappears when the medication is discontinued. This is a complex problem that must be better studied to be understood in order to prevent its occurrence and to find the best treatment.

Antibiotic therapy: a major cause of drug-induced jaundice in southwest England

OBJECTIVE

To determine the incidence and causes of drug-induced jaundice in a rural community.

METHODS

A retrospective analysis of 800 patients presenting to a single-centre jaundice referral system serving a community of 400 000 over a period of 66 months (1998-2004). Standard criteria for drug-induced liver injury were applied to patients with a putative diagnosis of drug-induced jaundice. The incidence rates per prescription of drug-induced jaundice caused by co-amoxiclav and flucloxacillin were derived from local and national annual prescription rates.

RESULTS

The incidence of drug-induced jaundice was 1.27 (confidence limits 0.85-1.8) per 100 000 per annum in a total of 28 patients (17 men, mean age 69 years). Antibiotics were the commonest cause of jaundice (n=21). Of these, co-amoxiclav (n=9) and flucloxacillin (n=7) caused the majority with an incidence rate per 100 000 prescriptions of 9.91 (4.6-18.0) and 3.60 (1.5-7.2), respectively. Co-amoxiclav-induced jaundice was observed more commonly in elderly males (age 65 years, M : F 7 : 2). In those patients with flucloxacillin or co-amoxiclav-induced jaundice, bilirubin ranged from 54 to 599 mumol/l (267 mumol/l) with a resolution of jaundice between 30 and 90 days. Counselling with regard to potential drug-induced liver injury and reporting of the adverse reaction had been performed in 1/28 patients.

CONCLUSIONS

8.1% patients with no biliary obstruction and jaundice had a drug-induced and predominantly antibiotic-related aetiology particularly affecting an elderly population. We recommend that all patients receiving co-amoxiclav and flucloxacillin should be counselled before the therapy regarding the potential risk of jaundice and that an alternative antibiotic to co-amoxiclav is used if possible in men over the age of 60 years.

Hepatitis caused by the herbal remedy Teucrium polium L

Herbal remedies have become increasingly popular throughout the globe as a result of disappointment with conventional medicines and also of the alleged belief that herbal preparations are basically harmless. On the other hand, their effects can be exceedingly potent or even lethal if used improperly. Drugs and other chemicals account for less than 5% of cases of jaundice or acute hepatitis and smaller number of cases of chronic liver disease. Drug reactions can mimic any hepatobiliary disease, posing a diagnostic challenge for physicians and pathologists. Hepatotoxicity generally occurs after approximately 2 months of ingestion and consists of a non-specific hepatitis, which usually runs a benign course. Typical features include anorexia, nausea, abdominal pain, and jaundice associated with a marked elevation in serum aminotransferases. We present a case of acute hepatitis in a 70-year-old farmer, using Teucrium polium (golden germander) as hypoglycaemic aid. The patient presented only with jaundice, after 1 month's consumption of large quantities of this herb in a tea form.

Experimental models of acute and chronic liver failure in nude mice to study hepatocyte transplantation

Although hepatocyte transplantation is a promising therapy for acute liver failure in human, there is still a lack of animal models suffering from hepatic injury in which the benefits of hepatocyte transplantation could be evaluated solely, without the bias caused by immunosuppression. As a consequence, the aim of the study was first to develop reproducible models of partial hepatectomy and of thioacetamide (TA)- or Jo2-induced acute liver failure in nude mice. Chronic liver disease was also investigated by repeated injections of sublethal doses of thioacetamide. Survival rates, routine histologic observations, alanin aminotransferase sera content, Ki67, and caspase 3 immunodetection were investigated both after 40% partial hepatectomy and after toxic-induced damages. Liver injuries were more severe and/or precocious in nude mice than in Balb/c mice for a given treatment with a maximum of acute injury obtained 24 h after single toxic injection, and were found to be transitory and reversible within 10 days. Toxics induced apoptosis followed by necrosis, confirming recent published data. Onset of fibrosis leading to reproducible chronic cirrhosis in nude mice correlated with increasing number of Ki67-positive cells, indicating that high levels of cell proliferation occurred. Chronic cirrhosis progressively reversed to fibrosis when the treatment ceased. Preliminary results demonstrated that engrafted xenogeneic hepatocytes could be detected in the host liver by anti-MHC class I immunohistochemistry. Fractions enriched in 2n or 4n hepatocytes by cell sorting using a flow cytometer were equivalent to the unpurified fraction in terms of engraftment in control nude mice or in nude mice subjected to PH. However, in mice suffering from liver injury 24 h after Jo2 or TA treatment, the engraftment of 2n hepatocytes was about twice that of an unpurified hepatocyte population or of a population enriched in 4n hepatocytes.

Flucloxacillin-induced aplastic anaemia and liver failure

Flucloxacillin is a commonly prescribed semisynthetic penicillinase-resistant penicillin primarily used for the treatment of cutaneous staphylococcal infections. It is well-recognized that flucloxacillin may occasionally result in fatal hepatic injury. We report the case of a 40-year-old woman who developed fulminant hepatic failure and aplastic anaemia following a course of oral flucloxacillin. At the time of transplantation the patient was severely neutropenic. Post-transplant, the patient received single donor leucocyte transfusions, which resulted in a dramatic increase in neutrophil count. The patient was discharged from hospital after 120 days with normal liver function and recovered bone marrow. In this report, we discuss the care of patients with aplastic anaemia in the peritransplant setting.

Reduction of Drug Toxicity Using Dendrimers Based on Melamine

Dendrimers based on melamine can reduce the organ toxicity of solubilized cancer drugs administered by intraperitoneal injection. Methotrexate and 6-mercaptopurine, both FDA approved anticancer drugs, are known hepatotoxins. The solubility of these molecules can be increased by mixing them with a dendrimer based on melamine. C3H mice were administered subchronic doses of methotrexate or 6-mercaptopurine with and without a solubilizing dendrimer. Forty-eight hours after dosing, the mice were sacrificed and serum was collected for biochemical analyses. The levels of alanine transaminase, ALT, were used to probe liver damage. When the drugs are encapsulated by the dendrimer, a significant reduction in hepatotoxicity is observed: ALT levels from the rescued groups (drug + dendrimer) were 27% (methotrexate) and 36% (6-mercaptopurine) lower than those of animals treated with the drug alone.

Oral Tetracyclines for Ocular Rosacea: An Evidence-Based Review of the Literature

PURPOSE

To review the basis for the use of oral tetracyclines in ocular rosacea.

METHODS

Review of the published literature.

RESULTS

Two prospective, masked, and placebo-controlled studies of oxytetracycline for ocular rosacea demonstrated a modest treatment benefit. Studies performed with tetracycline and doxycycline for ocular rosacea were not placebo controlled, and the optimal drug, dose, and schedule of administration were not evaluated.

CONCLUSIONS

Available evidence supports a moderate treatment benefit in ocular rosacea for oxytetracycline, a tetracycline derivative not currently available in the United States. The efficacies of doxycycline and tetracycline, including treatment effect, optimal dose, duration of therapy, and side effects when used for ocular rosacea have not been established.

Bile duct disorders

Drug-induced bile duct injury related prolonged or chronic cholestasis is recognized as a common side effect of treatment with several drugs. The severity and duration of the clinical symptoms suggest that this increase in number of reports is not only related to clinician and pathologists being increasingly aware of the condition, but also may represent a true increase in incidence likely related to a time-related growing experience with newer drugs. This clinical presentation encompasses a wide variety of features that may be the source of diagnostic difficulties, especially in the cases where cholestasis occurs days or weeks after the completion of therapy. Even more puzzling is the initial picture of hepatocholangitis, which may be silent and ensuing bile duct paucity with chronic anicteric cholestasis may be another source of diagnostic difficulties in the long-term. These diagnostic difficulties suggest that some of the cases of the so-called "idiopathic adulthood ductopenia" may originate from overlooked drug induced vanishing bile duct syndrome. The pathogenesis of the syndrome remains largely unknown and the determinants of prognosis and outcome. From reproducible data obtained in different studies investigating HLA-dependent predisposition, one may assume that genetics plays a major role even if other unknown additive factors are also likely involved. Severity of initial hepatocholangitis is likely to represent another important determinant of severity and prognosis, however to be assessed in larger longitudinal studies. Therapy of large bile duct injury mimics that of primary sclerosing cholangitis. Treatment of small bile duct injury remains disappointing. Corticosteroids are invariably ineffective. Ursodeoxycholic acid as been shown to induce improvement of clinical and biochemical cholestasis in some selected cases, its efficacy being however unpredictable. Preliminary data about the natural history of the vanishing bile duct syndrome suggest that therapy might be more effective when initiated early.

Higher occurrence of hepatotoxicity and rash in patients treated with oxacillin, compared with those treated with nafcillin and other commonly used antimicrobials

This study compared adverse drug reactions (ADRs) to oxacillin with those to nafcillin and other antibiotics. We reviewed the medical records of 222 children receiving outpatient parenteral antimicrobial therapy (OPAT) from February 1995 through June 1999. The diagnosis, antibiotics used, ADRs, action taken, and patient demographics were recorded. The most common ADRs were neutropenia (9.8%), rash (8.5%), and hepatotoxicity (3.8%). ADRs occurred more frequently in the oxacillin group (58.5%) than in the nafcillin group (29.3%; P=.004), the clindamycin group (12.5%; P<.001) and the "other" antibiotics group (14.4%; P<.001). Hepatotoxicity and rash occurred more frequently in the oxacillin group (22% and 31.7%, respectively) than in the nafcillin group (0% [P<.001] and 10.3% [P=.008]), the clindamycin group (1.4% [P<.001] and 8.3% [P=.001]), and the other antibiotics group (1.4% [P<.001] and 1.4% [P<.001]). On the basis of this retrospective analysis, oxacillin use in children was associated with a higher incidence of hepatotoxicity and rash, compared with the use of nafcillin and other intravenous antimicrobials.

Nimesulide-induced acute hepatitis

OBJECTIVE

To report the occurrence of nimesulide-induced acute hepatitis confirmed by biopsy and an in vitro lymphocyte toxicity assay.

CASE SUMMARY

A 54-year-old Arabic woman treated with nimesulide for chronic low back pain was admitted to the hospital with acute hepatitis confirmed by biopsy. Her liver function test results returned to normal within one month after nimesulide discontinuation. An in vitro lymphocyte toxicity assay confirmed that the liver injury was due to nimesulide exposure.

DISCUSSION

A case of acute hepatitis secondary to nimesulide, confirmed by biopsy and a laboratory in vitro assay, is described. Although the occurrence of clinically significant liver damage due to nonsteroidal antiinflammatory drugs (NSAIDs) is low, the enormous consumption of these drugs has made them an important cause of liver damage. Nimesulide, a relatively new NSAID commonly used in Europe, with a relative selectivity to cyclooxygenase type 2, can cause a wide range of liver injuries, from mild abnormal liver function to severe liver injuries. These effects are usually reversible on discontinuation of the drug, but occasionally can progress to fatal hepatic failure.

CONCLUSIONS

Drug-induced acute hepatitis is a well-recognized adverse effect of many drugs, including nimesuilde. Identification of a drug as a cause for this life-threatening disease is important because the discontinuation of it may be life saving. This article confirms the occurrence of nimesulide-induced hepatitis. It also highlights the importance of monitoring liver function test results after initiating therapy with such a drug.

The risk of liver damage associated with minocycline: a comparative study

Using the General Practice Research Database, the authors performed (1) a cohort analysis comparing the incidence of liver dysfunction in new users of minocycline with new users of oxytetracycline/tetracycline and (2) a case control study assessing antibiotic exposure in new cases of liver dysfunction and controls without liver dysfunction. In new users, the incidence of liver dysfunction in those exposed to minocycline was 1.04 cases/10,000 exposed person months (EPM) and 0.69 cases/10,000 EPM in those exposed to oxytetracycline/tetracycline (relative risk 1.51 [CI95: 0.63, 3.65]). The risk in both groups was greatest in the first month of use. The adjusted odds ratio (ORadj) of liver dysfunction associated with exposure to minocycline compared with nonuse was 2.10 (CI95: 1.30, 3.40); for oxytetracycline/tetracycline, the ORadj was 1.46 (CI95: 0.81, 2.64); and for exposure to erythromycin, the ORadj was 1.64 (CI95: 0.71, 3.80). The authors thus support a weak association between the use of oral antibiotics and liver dysfunction in patients with acne. The risk associated with exposure to minocycline appears to be very small. The cohort analysis demonstrated that any risk associated with minocycline was not significantly greater than that associated with oxytetracycline/tetracycline exposure.

Hyperbilirubinemia during quinupristin-dalfopristin therapy in liver transplant recipients: correlation with available liver biopsy results

STUDY OBJECTIVE

To review the liver histopathology in transplant recipients who developed hyperbilirubinemia during therapy with quinupristin-dalfopristin, a new streptogramin antibiotic, and to ascertain whether objective histologic evidence of adverse drug effect could be correlated to serum bilirubin levels.

DESIGN

Retrospective analysis.

SETTING

University of Pittsburgh Medical Center.

PATIENTS

From a database of 34 liver recipients who received quinupristin-dalfopristin for vancomycin-resistant Enterococcus faecium infection who were prospectively enrolled in a multicenter, open-label, emergency-use protocol, the data for a subset of 25 patients who underwent one or more liver biopsies during therapy were reviewed for this study.

INTERVENTIONS

Quinupristin-dalfopristin was administered intravenously at 7.5 mg/kg every 8 hours. Available serum bilirubin levels from before, during, and 1 week after therapy were tabulated. Liver biopsy results obtained within 1 week before and during therapy were retrospectively reviewed. Histopathologic results were characterized and correlated to bilirubin level.

MEASUREMENTS AND MAIN RESULTS

Cholestatic changes were already present in 15 of 17 patients who underwent biopsy before therapy. During therapy, the most common findings from 40 biopsies (25 patients) were cholestasis (33 biopsies), acute rejection (10), and periportal inflammation (8). There was no evidence of drug-specific histopathologic injury.

CONCLUSION

Hyperbilirubinemia in these patients was likely multifactorial and most frequently due to sepsis and prior graft injury.

The use of anti-inflammatory drugs in cancer pain

The role of non-steroidal anti-inflammatory drugs (NSAIDs) in cancer pain has been well established in the treatment of mild pain and also alone or in association with opioids for the treatment of moderate to severe pain. Acutely, NSAIDs may be more than mild analgesics, and may provide additional analgesia when combined with opioids. However, NSAIDs have ceiling effects and there is no therapeutic gain from increasing dosages beyond those recommended. As there is no clearly superior NSAID, the choice should be based on experience and the toxicity profile that probably relates to the COX-1:COX-2 ratio. Among the older drugs, ibuprofen seems to have these properties.Non-steroidal anti-inflammatory drugs have been shown to have an opioid-sparing effect. Although the value of a simple narcotic-sparing effect may be questioned in cancer pain treatment, the use of NSAIDs may be useful when the increase in opioid dosage determine the occurrence of opioid toxicity. Like opioids, NSAIDs should not be considered analgesics for a specific type or cause of pain. There is a lack of evidence for any difference between different routes of NSAIDs administration. The long-term toxicity of NSAIDs in cancer pain is poorly defined due to a lack of studies. A variety of strategies have been used in an attempt to reduce the risks associated with NSAID therapy. Those NSAIDs that are weak COX-1 inhibitors may be preferred. In addition, concomitant administration of misoprostol is recommended in patients at increased risk for upper gastrointestinal complications.

Drug-Induced Liver Disease

Drug-induced liver disease can result from dosage-dependent hepatotoxicity or from adverse reactions to drugs used in therapeutic dosage. The latter idiosyncratic hepatotoxins can cause clinical syndromes that mimic all known liver diseases, so that drugs must be considered as the possible causal agent for all unexplained cases of liver disease. The only specific antidote for dosage-dependent hepatotoxicity is n-acetylcysteine (and some other sulfhydryl donors), which is highly effective for the prevention of significant hepatotoxicity after acetaminophen overdose. Early diagnosis and prompt withdrawal of the offending drug is the key to successful management of most drug-induced liver diseases. The mainstay of treatment is supportive care, with careful monitoring for signs of acute liver failure or progression to chronic liver disease. In cases of liver failure, close liaison with a liver transplant center is crucial; referral for liver transplantation should be considered if standard transplant criteria are fulfilled. Pruritus is a major symptom of drug-induced cholestasis; protracted cases may respond to ursodeoxycholic acid. Corticosteroids can be considered for cases of drug-induced hepatitis, especially those with evidence of immune hypersensitivity, if no improvement is seen in 8 to 12 weeks. Although there are no controlled trials, some patients may respond favorably.

Minocycline as a cause of drug-induced autoimmune hepatitis. Report of four cases and comparison with autoimmune hepatitis

We describe the clinical and liver biopsy morphologic features for 4 patients with minocycline-induced autoimmune hepatitis (group 1). We compared the serum laboratory values and liver biopsy findings from group 1 with those from 10 patients with sporadic autoimmune hepatitis (group 2). All patients in group 1 had positive serum antinuclear antibody titers, but none had positive serum anti-smooth muscle antibody titers. The morphologic findings of group 1 biopsies were those of autoimmune hepatitis in all 4 patients. In addition, 1 of these biopsy specimens also had scattered single eosinophils, unlike autoimmune hepatitis. The mean histologic activity index scores for patients in groups 1 and 2, respectively, were 6.7 and 5.4. No patients in group 1 had marked bridging fibrosis or cirrhosis, compared with 4 of 10 patients in group 2. Minocycline-induced autoimmune hepatitis is usually identical to sporadic autoimmune hepatitis. The absence of eosinophils does not exclude the possibility of a minocycline cause. In the absence of clinical or morphologic differences, a recent ingestion of minocycline should be excluded before the diagnosis of sporadic autoimmune hepatitis is established. Whether the drug is unmasking latent autoimmune hepatitis is unclear.

Liver damage associated with minocycline use in acne: a systematic review of the published literature and pharmacovigilance data

OBJECTIVE

Minocycline is an antibacterial drug used in the treatment of acne. Concern has been expressed over the possibility of severe adverse reactions to minocycline, including hepatitis. This study set out to identify and characterise reported cases of hepatotoxicity associated with the use of minocycline.

METHODS

A systematic review of the literature including a search of computerised databases and analysis of data from the Uppsala Monitoring Centre (WHO Collaborating Centre for International Drug Monitoring) was conducted. The review involved a search for original case reports involving liver damage in people using minocycline. Patients taking minocycline for reasons other than acne or those given intravenous minocycline were excluded. The search strategy involved an enquiry of computerised databases and a search for secondary references. Cases were then classified appropriately.

RESULTS

65 reported cases of hepatitis or liver damage in association with minocycline from either case reports or case series were identified from the literature review. 58% of cases occurred in females and 94% were aged under 40 years. For 20 case reports there was insufficient information to classify the type of event, but for the remaining 45, 2 types of hepatic reaction were recognised: autoimmune hepatitis associated with lupus-like symptoms occurring after a median duration of exposure to minocycline of 365 days in females (n = 20) and 730 days in males (n = 9), hypersensitivity reaction associated with eosinophilia and exfoliative dermatitis occurring within 35 days of therapy (n = 16). Reports to the WHO of hepatic adverse drug reactions associated with minocycline accounted for 6% (493) of all minocycline-related adverse drug reactions (8025). The pattern of distribution in relation to exposure demonstrated 2 groups, similar to that described by the case reports.

CONCLUSIONS

Severe cases of minocycline-associated hepatotoxicity appear to be a hypersensitivity reaction and occur within a few weeks of commencing therapy. An autoimmune hepatitis usually presents after exposure to minocycline of a year or more, is more common in women and is sometimes associated with lupus-like symptoms.

Cetirizine-induce cholestasis

Cetirizine, a human metabolite of hydroxyzine, is a selective H1-receptor antagonist currently approved for the treatment of seasonal allergic rhinitis, perennial allergic rhinitis, and chronic urticaria. In U.S. clinical trials, transient reversible hepatic transaminase elevations were observed in <2% of patients during cetirizine therapy. We report a case of cetirizine-induced cholestasis in a 28-year-old man with no previous hepatobiliary disease after a 2-year period of taking cetirizine on a daily basis. The treatment of this patient included the use of ursodeoxycholic acid, as well as hydroxyzine, for symptomatic relief of pruritus. In light of the patient's clinical and biochemical improvement while using hydroxyzine, it appears that the hepatic metabolism of hydroxyzine to metabolites, including cetirizine, is not involved in the pathogenesis of this particular case of drug-induced hepatotoxicity. Cetirizine should be considered as a potential cause of drug-induced cholestasis.

Update: the clinical importance of acetaminophen hepatotoxicity in non-alcoholic and alcoholic subjects

Acetaminophen (paracetamol) is one of the most commonly used over-the-counter medications. Taken in doses greater than 150 mg/kg/day (>10 g), it usually causes acute liver failure. The authors review mainly the management of acetaminophen toxicity in both users and nonusers of alcohol. Chronic alcoholics are a special subgroup, who risk serious toxicity when taking acetaminophen, even in therapeutic doses. The acetaminophen-alcohol interaction is complex, because acute and chronic ethanol have opposite effects. This review also considers physiological and clinical changes, as well as the diagnosis and treatment of acetaminophen poisoning.

Cytochrome P450 2E1: its clinical and toxicological role

Cytochrome (CYP) P450 2E1 is clinically and toxicologically important and it is constitutively expressed in the liver and many other tissues. In contrast to many other CYP isoenzymes, indisputable evidence for a functionally important polymorphism of CYP2E1 in the human population is lacking. CYP2E1 metabolizes a wide variety of chemicals with different structures, in particular small and hydrophobic compounds, including potential cytotoxic and carcinogenic agents. In addition, chlorzoxazone and trimethadione metabolism are good CYP2E1 probes for liver disease in vivo and in vitro. In the future, methods for fully analysing the function of CYP2E1 using knockout mice will be established. This article reviews recent advances in our understanding of the role of human CYP2E1 in drug metabolism.

Hepatitis from 5-methoxypsoralen occurring in a patient with previous flucloxacillin hepatitis

A 55-year-old woman with psoriasis vulgaris was treated with oral 5-methoxypsoralen and UVA photochemotherapy. After 40 treatments over 3 months she became unwell with hepatitis attributable to the psoralen. Six years earlier she developed cholestatic hepatitis to flucloxacillin. A previous history of drug-induced reactions should be sought before prescribing further drugs with similar adverse effects.

Inflammation-induced cholestasis

Inflammatory cytokines produced in response to various infectious and non-infectious stimuli are potent inducers of intrahepatic cholestasis (inflammation-induced cholestasis). The cholestatic effect of cytokines results mainly from inhibition of expression and function of hepatocellular transport systems which normally mediate hepatic uptake and biliary excretion of bile salts and various non-bile salt organic anions (e.g. bilirubin). These cytokine effects are reversible and bile secretory function is restored upon disappearance of the inflammatory injury. This review summarizes the clinical, pathophysiological and molecular aspects of inflammation-induced cholestasis.

Novel CXCR2-dependent liver regenerative qualities of ELR-containing CXC chemokines

Severe acute liver injury due to accidental or intentional acetaminophen overdose presents a major clinical dilemma often requiring liver transplantation. In the present study, liver regeneration after profound liver injury in mice challenged with acetaminophen was facilitated by the exogenous addition of ELR-containing CXC chemokines such as macrophage inflammatory protein-2 (MIP-2), epithelial neutrophil-activating protein-78 (ENA-78), or interleukin 8. Intravenous administration of ELR-CXC chemokines or N-acetyl-cysteine (NAC) immediately after acetaminophen challenge in mice significantly reduced histological and biochemical markers of hepatic injury. However, when the intervention was delayed until 10 h after acetaminophen challenge, only ELR-CXC chemokines significantly reduced liver injury and mouse mortality. The delayed addition of ELR-CXC chemokines to cultured hepatocytes maintained the proliferation of these cells in a CXCR2-dependent fashion after acetaminophen challenge whereas delayed NAC treatment did not. These observations demonstrate that ELR-CXC chemokines represent novel hepatic regenerative factors that exhibit prolonged therapeutic effects after acetaminophen-induced hepatotoxicity.

Macrophage inflammatory protein-2 gene therapy attenuates adenovirus- and acetaminophen-mediated hepatic injury

Profound hepatocellular injury is often a consequence of adenovirus-mediated gene therapy or acetaminophen ingestion. The aim of the present study was to examine the role of a CXC chemokine, macrophage inflammatory protein-2 (MIP-2), in the hepatotoxic response by mice infected with adenovirus and challenged with acetaminophen. CD1 mice that received a replication-defective human type 5 adenovirus vector (Ad70-3) intravenously exhibited hepatic injury that peaked at 24 h after infection. In contrast, mice that received a similar adenovirus vector containing a rodent MIP-2 cDNA insert had no hepatic injury at any time after infection. The combination of Ad70-3 infection and an intraperitoneal challenge with 400 mg/kg of acetaminophen was fatal in 50% of the mice, but only 10% of the AdMIP-2 group receiving acetaminophen were similarly affected. Furthermore, AdMIP-2 mice had significantly lower hepatic injury and serum aminotransaminases compared with the Ad70-3 group. However, AdMIP-2 infection in mice lacking the CXC chemokine receptor that binds MIP-2, CXCR2, did not attenuate any of the markers of liver injury after adenovirus and acetaminophen challenge. AdMIP-2 treatment of CD1 mice was also associated with significantly decreased leukocyte infiltration into the liver and an earlier increase in hepatic 3H-thymidine incorporation compared with the control group. Taken together, these data demonstrate that MIP-2 has a protective role in both adenovirus- and acetaminophen-mediated hepatotoxicity, and suggest that MIP-2 may promote rapid hepatic regeneration following acute hepatic injury.

Genomic structure of the canalicular multispecific organic anion-transporter gene (MRP2/cMOAT) and mutations in the ATP-binding-cassette region in Dubin-Johnson syndrome

Dubin-Johnson syndrome (DJS) is an autosomal recessive disease characterized by conjugated hyperbilirubinemia. Previous studies of the defects in the human canalicular multispecific organic anion transporter gene (MRP2/cMOAT) in patients with DJS have suggested that the gene defects are responsible for DJS. In this study, we determined the exon/intron structure of the human MRP2/cMOAT gene and further characterized mutations in patients with DJS. The human MRP2/cMOAT gene contains 32 exons, and it has a structure that is highly conserved with that of another ATP-binding-cassette gene, that for a multidrug resistance-associated protein. We then identified three mutations, including two novel ones. All mutations identified to date are in the cytoplasmic domain, which includes the two ATP-binding cassettes and the linker region, or adjacent putative transmembrane domain. Our results confirm that MRP2/cMOAT is the gene responsible for DJS. The finding that mutations are concentrated in the first ATP-binding-cassette domain strongly suggests that a disruption of this region is a critical route to loss of function.

Is there any use for nontraditional or alternative therapies in patients with chronic liver disease?

There has been a substantial increase in the use of so-called complementary and alternative therapies by patients with liver disease. Although many such modalities are available, herbal therapies are the most popular, and of these remedies, silymarin extracted from the milk thistle is most widely subscribed to as a remedy for liver diseases. Available evidence points to a potential, but unproven, benefit for this as well as other therapies based on free radical scavenger or antioxidant principles in treating patients with liver disease. These therapies deserve further investigation through experimental studies and well-controlled clinical trials. Benefits to patients from these therapies, especially to patients with established cirrhosis, are most likely to be modest and insignificant. Conversely, the hepatotoxic potential of some alternative treatments is well recognized. As practitioners educating and treating patients with liver disease, we are obliged to be informed about popular alternative therapies, understanding of our patients' need to be partners in their care, and open-minded to the possibility that some benefit may come from some therapies currently regarded as alternative. We need to be effective and tolerant in learning about which alternative treatments our patients are taking, so that we can monitor their effects if any and counsel appropriately against those that may cause harm.