Drug-induced prolonged cholestasis in adults: a histological semiquantitative study demonstrating progressive ductopenia

Histopathological Features Predicting Long-term Clinical Outcomes in Patients with Vanishing Bile Duct Syndrome

Background and Aims

The clinicopathological features and long-term outcomes of patients with vanishing bile duct syndrome (VBDS) have yet to be elucidated. The study aims to investigate these features and identify factors associated with poor prognosis.

Methods

This multicenter retrospective study recruited patients with liver biopsy-proven VBDS who were followed up at five hospitals in northern China from January 2003 to April 2022. Clinical and pathological data at time of biopsy were reviewed. Clinical outcomes including cirrhosis, decompensation events, liver transplantation (LT), and liver-related death were recorded. Cox regression analysis was used to identify the risk factors associated with poor outcomes.

Results

A total of 183 patients were included. The median age was 47 years, with 77.6% being women. During a median follow-up of 4.8 years, 88 patients developed compensated or decompensated cirrhosis, 27 died, and 15 received LT. Multivariate Cox regression analysis showed that hepatocellular cholestasis (HR 2.953, 95% CI: 1.437-6.069), foam cells (HR 2.349, 95% CI: 1.092-5.053), and advanced fibrosis (HR 2.524, 95% CI: 1.313-4.851) were independent predictors of LT or liver-related deaths. A nomogram formulated with the above factors showed good consistency with a concordance index of 0.746 (95% CI: 0.706-0.785).

Conclusions

Nearly half of VBDS patients studied progressed to end-stage liver disease and 23% of them had LT or liver-related death within two years of diagnosis. Hepatocellular cholestasis, foam cells and advanced fibrosis rather than the degree of bile duct loss or underlying etiologies were independently associated with poor prognosis in VBDS patients.

Cloxacillin-induced acute vanishing bile duct syndrome: a case study and literature review

Ductopenia is often regarded as a chronic process where ≥50% of portal tracts lack bile ducts, which is also known as vanishing bile duct syndrome (VBDS). One etiology is drug-induced liver injury. Cloxacillin, an anti-staphylococcal penicillin, typically causes "bland" cholestasis. We present the first case of cloxacillin-induced acute ductopenia or VBDS and a review of published cloxacillin-induced liver injuries. A 66-year-old woman with no prior liver disease, but known penicillin allergy, was treated for post-carotid angioplasty staphylococcal infection with 6 weeks of cloxacillin. She presented with a two-week history of weakness and jaundice. Laboratory work-up showed elevated liver enzymes with a cholestatic pattern, hyperbilirubinemia, and eosinophilia. She required ICU transfer for hypotension and was started empirically on prednisone. Liver biopsy revealed severe centrilobular cholestasis, mild necroinflammation, and ductopenia with epithelial injury, but no ductular reaction. Two-month later, she was discharged on hydrocortisone and ursodiol with persistently elevated alkaline phosphatase and bilirubin. She was considered for liver transplantation but died of liver failure four months later. Four additional articles were found with histopathologic descriptions of cloxacillin-related liver injury. These included portal inflammation, cholestasis and mild necroinflammation. Clinical features were reported in two cases; both had mild symptoms with cholestatic liver enzymes and hyperbilirubinemia. Both patients recovered completely within 10-60 days. Cloxacillin-induced cholestasis can be secondary to acute ductopenia, which can result in worse clinical outcomes than previously described "bland" cholestasis. Liver biopsy is recommended to identify cases with acute VBDS.

Long-term sequelae of drug-induced liver injury

Drug-induced liver injury (DILI) has a very variable clinical and biochemical phenotype and differs widely in severity, from mild injury to life-threatening liver failure. Chronic injury has also been reported to occur at a variable frequency, ranging from 3.4% to 39%, 6-12 months after discontinuing the implicated agent. This wide range is probably related to various definitions of chronic liver injury and variable selection of patients. The long-term sequalae of this chronic injury in terms of morbidity and mortality are unclear, although rare vanishing bile duct syndrome is associated with an unfavourable prognosis, with increased risk of chronic liver failure and need for liver transplantation. Other forms of long-term sequalae associated with DILI are progressive fibrosis, autoimmune-like hepatitis, secondary sclerosing cholangitis, sinusoidal obstruction syndrome and, as a common final stage, the development of cirrhosis, portal hypertension and its complications. Immune checkpoint inhibitors, which can cause an autoimmune-like phenotype have also recently been shown to cause sclerosing cholangitis with cytotoxic T CD8+ cell infiltration in biliary tracts. DILI has been shown to have a significant impact on health-related quality of life but very little is known about its psychological consequences in the long-term. Further investigations with structured long-term follow-up and periodic quality of life surveys are needed to assess the impact of DILI on psychological outcomes, particularly in those with chronic sequelae.

Drug-Induced Vanishing Bile Duct Syndrome: From Pathogenesis to Diagnosis and Therapeutics

The most concerned issue in the context of drug/herb-induced chronic cholestasis is vanishing bile duct syndrome. The progressive destruction of intrahepatic bile ducts leading to ductopenia is usually not dose dependent, and has a delayed onset that should be suspected when abnormal serum cholestasis enzyme levels persist despite drug withdrawal. Immune-mediated cholangiocyte injury, direct cholangiocyte damage by drugs or their metabolites once in bile, and sustained exposure to toxic bile salts when biliary epithelium protective defenses are impaired are the main mechanisms of cholangiolar damage. Current therapeutic alternatives are scarce and have not shown consistent beneficial effects so far. This review will summarize the current literature on the main diagnostic tools of ductopenia and its histological features, and the differential diagnostic with other ductopenic diseases. In addition, pathomechanisms will be addressed, as well as the connection between them and the supportive and curative strategies for ductopenia management.

Chronic Drug-Induced Liver Injury: Updates and Future Challenges

Chronic drug-induced liver injury (DILI), defined as DILI with persistent liver injury more than one year after the first onset by the latest European guidelines, is a notable challenge globally with big issues of defining causality and establishing effective treatment. About 20% of patients with DILI develop into chronic DILI. Chronic DILI manifests as persistent or repeated inflammatory or diminishing bile ducts, even progresses to cirrhosis and needs liver transplantation eventually. However, research on chronic DILI over the last decades is still lacking, and the incidence, phenotypes, mechanisms, risk factors, and treatment have not been fully understood. In this paper, we reviewed the definition of chronic DILI, updated clinical studies in terms of incidence, special manifestations, and promising risk factors of chronic DILI, along with the recent progress and challenges in glucocorticoid therapy.

The Role of Sirtuin 3 in Radiation-Induced Long-Term Persistent Liver Injury

In patients with abdominal region cancers, ionizing radiation (IR)-induced long-term liver injury is a major limiting factor in the use of radiotherapy. Previously, the major mitochondrial deacetylase, sirtuin 3 (SIRT3), has been implicated to play an important role in the development of acute liver injury after total body irradiation but no studies to date have examined the role of SIRT3 in liver's chronic response to radiation. In the current study, ten-month-old Sirt3^-/- and Sirt3^+/+ male mice received 24 Gy radiation targeted to liver. Six months after exposure, irradiated Sirt3^-/- mice livers demonstrated histopathological elevations in inflammatory infiltration, the loss of mature bile ducts and higher DNA damage (TUNEL) as well as protein oxidation (3-nitrotyrosine). In addition, increased expression of inflammatory chemokines (IL-6, IL-1β, TGF-β) and fibrotic factors (Procollagen 1, α-SMA) were also measured in Sirt3^-/- mice following 24 Gy IR. The alterations measured in enzymatic activities of catalase, glutathione peroxidase, and glutathione reductase in the livers of irradiated Sirt3^-/- mice also implied that hydrogen peroxide and hydroperoxide sensitive signaling cascades in the absence of SIRT3 might contribute to the IR-induced long-term liver injury.

EASL Clinical Practice Guidelines: Drug-induced liver injury

Idiosyncratic (unpredictable) drug-induced liver injury is one of the most challenging liver disorders faced by hepatologists, because of the myriad of drugs used in clinical practice, available herbs and dietary supplements with hepatotoxic potential, the ability of the condition to present with a variety of clinical and pathological phenotypes and the current absence of specific biomarkers. This makes the diagnosis of drug-induced liver injury an uncertain process, requiring a high degree of awareness of the condition and the careful exclusion of alternative aetiologies of liver disease. Idiosyncratic hepatotoxicity can be severe, leading to a particularly serious variety of acute liver failure for which no effective therapy has yet been developed. These Clinical Practice Guidelines summarize the available evidence on risk factors, diagnosis, management and risk minimization strategies for drug-induced liver jury.

Long-Term Outcomes After Drug-Induced Liver Injury

Purpose of the review

This review serves to update the reader on emerging data regarding a spectrum of drug-induced liver injury (DILI) outcomes that lie between complete resolution and acute liver failure. Such outcomes can range from mild chronic injury to late liver failure and mortality.

Recent findings

Several large registries are maturing with large numbers of DILI cases thus shedding light on outcomes including chronic injury and late fatality. We cover definitions commonly used to describe resolution versus chronic injury and mortality due to DILI. We look at rates of occurrence for these different outcomes in major registries. Three specific types of chronic DILI that are illustrative but also easily missed by clinicians are also described.

Summary

A small but important proportion of DILI cases do not resolve, going on to develop chronic injury and even liver failure. Defining and recognizing these cases is a challenge because DILI is rare, and chronic injury rarer still. Large registries are beginning to define these previously overlooked long term outcomes.

Drug-induced cholestasis

Cholestatic drug-induced liver injury (DILI) can be a diagnostic challenge due to a large differential diagnosis, variability in clinical presentation, and lack of serologic biomarkers associated with this condition. The clinical presentation of drug-induced cholestasis includes bland cholestasis, cholestatic hepatitis, secondary sclerosing cholangitis, and vanishing bile duct syndrome. The associate mortality of cholestatic DILI can be as high as 10%, and thus prompt recognition and removal of the offending agent is of critical importance. Several risk factors have been identified for drug-induced cholestasis, including older age, genetic determinants, and properties of certain medications. Antibiotics, particularly amoxicillin/clavulanate, remain the predominant cause of cholestatic DILI, although a variety of other medications associated with this condition have been identified. In this review, we summarize the presentation, clinical approach, risk factors, implicated medications, and management of drug-induced cholestatic liver injury. (Hepatology Communications 2017;1:726-735).

Clinical presentations and outcomes of bile duct loss caused by drugs and herbal and dietary supplements

Bile duct loss during the course of drug-induced liver injury is uncommon, but can be an indication of vanishing bile duct syndrome (VBDS). In this work, we assess the frequency, causes, clinical features, and outcomes of cases of drug-induced liver injury with histologically proven bile duct loss. All cases of drug-induced liver injury enrolled into a prospective database over a 10-year period that had undergone liver biopsies (n = 363) were scored for the presence of bile duct loss and assessed for clinical and laboratory features, causes, and outcomes. Twenty-six of the 363 patients (7%) with drug-, herbal-, or dietary-supplement-associated liver injury had bile duct loss on liver biopsy, which was moderate to severe (<50% of portal areas with bile ducts) in 14 and mild (50%-75%) in 12. The presenting clinical features of the 26 cases varied, but the most common clinical pattern was a severe cholestatic hepatitis. The implicated agents included amoxicillin/clavulanate (n = 3), temozolomide (n = 3), various herbal products (n = 3), azithromycin (n = 2), and 15 other medications or dietary supplements. Compared to those without, those with bile duct loss were more likely to develop chronic liver injury (94% vs. 47%), which was usually cholestatic and sometimes severe. Five patients died and 2 others underwent liver transplantation for progressive cholestasis despite treatment with corticosteroids and ursodiol. The most predictive factor of poor outcome was the degree of bile duct loss on liver biopsy.

CONCLUSION

Bile duct loss during acute cholestatic hepatitis is an ominous early indicator of possible VBDS, for which at present there are no known means of prevention or therapy. (Hepatology 2017;65:1267-1277).

Clinical characteristics of drug-induced liver injury and primary biliary cirrhosis

AIM

To summarize and compare the clinical characteristics of drug-induced liver injury (DILI) and primary biliary cirrhosis (PBC).

METHODS

A total of 124 patients with DILI and 116 patients with PBC treated at Shengjing Hospital Affiliated to China Medical University from 2005 to 2013 were included. Demographic data (sex and age), biochemical indexes (total protein, albumin, alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, indirect bilirubin, alkaline phosphatase, and gamma glutamyltransferase), immunological indexes [immunoglobulin (Ig) A, IgG, IgM, antinuclear antibody, anti-smooth muscle antibody, anti-mitochondrial antibody, and anti-mitochondrial antibodies] and pathological findings were compared in PBC patients, untyped DILI patients and patients with different types of DILI (hepatocellular type, cholestatic type and mixed type).

RESULTS

There were significant differences in age and gender distribution between DILI patients and PBC patients. Biochemical indexes (except ALB), immunological indexes, positive rates of autoantibodies (except SMA), and number of cases of patients with different ANA titers (except the group at a titer of 1:10000) significantly differed between DILI patients and PBC patients. Biochemical indexes, immunological indexes, and positive rate of autoantibodies were not quite similar in different types of DILI. PBC was histologically characterized mainly by edematous degeneration of hepatocytes (n = 30), inflammatory cell infiltration around bile ducts (n = 29), and atypical hyperplasia of small bile ducts (n = 28). DILI manifested mainly as fatty degeneration of hepatocytes (n = 15) and spotty necrosis or loss of hepatocytes (n = 14).

CONCLUSION

Although DILI and PBC share some similar laboratory tests (biochemical and immunological indexes) and pathological findings, they also show some distinct characteristics, which are helpful to the differential diagnosis of the two diseases.

The Art and Science of Diagnosing and Managing Drug-induced Liver Injury in 2015 and Beyond

Drug-induced liver injury (DILI) remains a leading reason why new compounds are dropped from further study or are the subject of product warnings and regulatory actions. Hy's Law of drug-induced hepatocellular jaundice causing a case-fatality rate or need for transplant of 10% or higher has been validated in several large national registries, including the ongoing, prospective U.S. Drug-Induced Liver Injury Network. It serves as the basis for stopping rules in clinical trials and in clinical practice. Because DILI can mimic all known causes of acute and chronic liver disease, establishing causality can be difficult. Histopathologic findings are often nonspecific and rarely, if ever, considered pathognomonic. A daily drug dose >50-100 mg is more likely to be hepatotoxic than does <10 mg, especially if the compound is highly lipophilic or undergoes extensive hepatic metabolism. The quest for a predictive biomarker to replace alanine aminotransferase is ongoing. Markers of necrosis and apoptosis such as microRNA-122 and keratin 18 may prove useful in identifying patients at risk for severe injury when they initially present with a suspected acetaminophen overdose. Although a number of drugs causing idiosyncratic DILI have HLA associations that may allow for pre-prescription testing to prevent hepatotoxicity, the cost and relatively low frequency of injury among affected patients limit the current usefulness of such genome-wide association studies. Alanine aminotransferase monitoring is often recommended but has rarely been shown to be an effective method to prevent serious DILI. Guidelines on the diagnosis and management of DILI have recently been published, although specific therapies remain limited. The LiverTox Web site has been introduced as an interactive online virtual textbook that makes the latest information on more than 650 agents available to clinicians, regulators, and drug developers alike.

Expression of nestin in remodelling of α-naphthylisothiocyanate-induced acute bile duct injury in rats

The function of the intermediate filament protein nestin is poorly understood. The significance of nestin expression was assessed in α-naphthylisothiocyanate (ANIT)-induced cholangiocyte injury lesions in F344 rats. Liver samples obtained from rats injected intraperitoneally with ANIT (75 mg/kg) on post-injection days 0 (control) and 1-12 were labelled immunohistochemically for expression of nestin and markers specific for mesenchymal cells (vimentin), hepatic stellate cells (HSCs) (desmin and glial fibrillary acidic protein [GFAP]), endothelial cells (rat endothelial cell antigen [RECA]-1), cholangiocytes (cytokeratin [CK] 19) and cellular proliferation (Ki67). Cholangiocyte injury led to infiltration of neutrophils and macrophages followed by aggregation of mesenchymal cells and regeneration of bile ducts. Nestin expression was detected in mesenchymal cells (vimentin positive) on days 1-7 with a peak on days 3-5 and in newly-formed RECA-1-positive endothelial cells on day 3. Nestin expression was also observed in regenerating CK19-positive cholangiocytes on days 2-5, with a peak on day 3. Labelling for Ki67 showed proliferation of cholangiocytes, mesenchymal cells and HSCs. Real-time reverse transcriptase polymerase chain reaction with microdissected samples showed significantly elevated nestin mRNA on day 3. The findings suggest an association between nestin expression and cellular proliferation. Based on these findings, it was considered that nestin-expressing mesenchymal cells, HSCs and endothelial cells may be possible progenitors of repopulating cholangiocytes. Nestin expression may serve as an indicator for cellular remodelling and behaviour of injured and repopulating bile ducts.

Antibiotic induced liver injury: what about children?

Antimicrobial agents are important causes of drug-induced liver injury. They are responsible for about 45% of cases of drug hepatotoxicity. Hepatic damage mechanisms are intrinsic or idiosyncratic. Usually, antibiotics are responsible for idiosyncratic toxicity. This review summarizes the rate of incidence and clinical features of hepatotoxicity due to antibiotics and chemotherapics, with particular attention to data regarding paediatric population. Liver injury features have been systematically evaluated for the most commonly administered antibiotics and chemotherapics in adults, even though there is little information about other widely used compounds, as cephalosporine or clarithromycin, and about antibiotics active against multi-resistant bacteria, as carbapenems, vancomycin, clindamycin, and linezolid. By contrast, there is an abundance of case reports in paediatrics, but very few structured studies have been carried out in children. Children are an important class of antibiotic users, with specific metabolic characteristics, so more studies on them should be carried out.

Ibuprofen associated acute vanishing bile duct syndrome and toxic epidermal necrolysis in an infant

Acute vanishing bile duct syndrome, a rare but rapidly progressive destruction of the intrahepatic bile ducts with unknown pathogenesis, is most often a drug- or toxin-related. Toxic epidermal necrolysis is a serious dermatologic condition and a potentially life threatening disease, which is drug or infection induced. Ibuprofen associated acute vanishing bile duct syndrome and toxic epidermal necrolysis have not been reported previously in infants. We report a 7-month-old infant with ibuprofen associated toxic epidermal necrolysis, followed by severe and rapidly progressive vanishing bile duct syndrome. She recovered totally with supportive care.

Idiosyncratic drug hepatotoxicity: a 2008 update

Pharmaceutical preparations, and also herbal products and dietary supplements, are emerging contributors to severe forms of liver disease. Although acetaminophen intoxication is still the reason for many cases of drug-induced liver injury (DILI) in Western countries, the bulk of hepatic reactions to drugs are idiosyncratic. Only a small fraction of individuals exposed to a drug associated with liver injury will develop hepatotoxicity. Indeed, the rarity of this serious adverse event prevents its detection in clinical trials. The pathogenesis of idiosyncratic DILI is not well known because of a lack of reliable animal models, although it probably involves the metabolism of the drug and/or activation of the immune system. Different databases have described antibiotics, NSAIDs and anticonvulsants as the main group of drugs incriminated in DILI. Clinical presentation of DILI includes predominantly a hepatocellular type of damage, yet cholestatic and mixed types are also common; the determinants of the type of damage induced by a given drug are poorly understood. Analysis of pooled data has recently underlined the influence of older age in the cholestatic/mixed expression of liver injury, as well as the independent association of female gender, older age, aspartate aminotransferase levels with hepatocellular type of damage and high bilirubin levels with the risk of fulminant liver failure/death. In the long term (providing the patient survives the initial episode), persistent damage may occur in at least 6% of patients, with the cholestatic mixed type of damage more prone to becoming chronic, while in the hepatocellular pattern the severity is greater, with further likelihood of evolution to cirrhosis. Cardiovascular and CNS drugs are the main groups leading to chronic liver damage. The diagnosis of hepatotoxicity remains a difficult task owing to the lack of reliable markers for use in general clinical practice. Diagnostic algorithms may add consistency to clinical judgment by translating a suspicion into a quantitative score. Currently, the Council for International Organizations of Medical Sciences/Roussel Uclaf Causality Assessment Method instrument is considered the gold standard in causality assessment of hepatotoxicity, although there is probably room for improvement. Current efforts in collecting bona fide cases will make refinements of existing scales feasible. Efforts should also be directed towards the development of an abridged instrument for use in evaluating suspected drug-induced hepatotoxicity at the very beginning of the diagnosis and treatment process when clinical decisions need to be taken. The treatment of idiosyncratic DILI is largely supportive. Early suspicion and withdrawal of the offending agent is the most important therapeutic measure.

Hepatotoxicity of antibiotics: a review and update for the clinician

Collectively, the various classes of antibiotics are a leading cause of drug-induced liver injury (DILI). However, acute antibiotic-associated DILI can be difficult to diagnose, as the course of therapy is usually brief, and other confounding factors are often present. In addition to the broad clinicopathologic spectrum of hepatotoxicity associated with the antimicrobials, the underlying infectious disease being treated may itself be associated with hepatic dysfunction and jaundice. This review provides summarized information on several classes of antimicrobial agents, highlighting new agents causing DILI and updating information on older agents.

Intrahepatic cholestasis in common chronic liver diseases

BACKGROUND AND OBJECTIVE

Cholestasis represents the consequence of impaired bile formation and decrease in bile flow, generally classified as extra- and intrahepatic. Cholestasis is the pivotal hallmark of the so-called primary cholestatic liver diseases but may also emerge in other forms of chronic liver injury. The aim now was to summarise the current state of knowledge on intrahepatic cholestasis related to chronic liver diseases.

METHODS

For this overview on intrahepatic cholestasis in chronic liver disorders other than the 'classic' cholestatic liver diseases, selected references were retrieved by literature search in MEDLINE and textbooks were reviewed. All articles were selected that discussed pathophysiological and clinical aspects of intrahepatic cholestasis in the context of alcoholic liver disease, nonalcoholic fatty liver disease, chronic hepatitis B and C virus infections as well as drug-induced and granulomatous liver diseases. Titles referring to primary biliary cirrhosis and sclerosing cholangitis were excluded.

RESULTS AND CONCLUSIONS

Dependent on the aetiology, intrahepatic cholestasis is present at variable frequencies and in different disease stages in chronic liver diseases. Cholestasis secondary to chronic liver injury may denote a severe disease course and development of end-stage liver disease or specific disease variants. These findings indicate that 'secondary intrahepatic cholestasis' (SIC) can occur in the natural course of chronic liver diseases other than the primary cholestatic diseases, in particular in the setting of advanced disease progression.

Drug-induced cholestasis

Cholestasis caused by drugs is an important differential diagnosis in patients presenting with a biochemical cholestatic pattern. The extent of serologic tests and radiological imaging depends on the clinical context. The underlying condition of the patient and detailed information on drug use, results of rechallenge, and the documented hepatotoxicity of the drug are important to establish a diagnosis of drug-induced liver injury (DILI). Most cases of cholestatic DILI are mild, but in rare cases, ductopenia and cholestatic cirrhosis can develop. Approximately 10% of patients with cholestatic jaundice caused by drugs develop liver failure.

Vanishing bile duct syndrome in human immunodeficiency virus infected adults: A report of two cases

Vanishing bile duct syndrome (VBDS) is a group of rare disorders characterized by ductopenia, the progressive destruction and disappearance of intrahepatic bile ducts leading to cholestasis. Described in association with medications, autoimmune disorders, cancer, transplantation, and infections, the specific mechanisms of disease are not known. To date, only 4 cases of VBDS have been reported in human immunodeficiency virus (HIV) infected patients. We report 2 additional cases of HIV-associated VBDS and review the features common to the HIV-associated cases. Presentation includes hyperbilirubinemia, normal liver imaging, and negative viral and autoimmune hepatitis studies. In HIV-infected subjects, VBDS occurred at a range of CD4+ T-cell counts, in some cases following initiation or change in antiretroviral therapy. Lymphoma was associated with two cases; nevirapine, antibiotics, and viral co-infection were suggested as etiologies in the other cases. In HIV-positive patients with progressive cholestasis, early identification of VBDS and referral for transplantation may improve outcomes.

Drug associated vanishing bile duct syndrome combined with hemophagocytic lymphohistiocytosis

A 28-year-old woman with untreated autoimmune disorder, demonstrated skin rash and fever after taking Amoxicillin-clavulanate and developed progressive jaundice. A bone marrow aspiration indicated an increased number of macrophages with hemophagocytosis and liver biopsy showed pure centrilobular cholestasis with necrosis and some absence of portal bile ducts. Furthermore, a serological test for Epstein-Barr virus was positive. Under treatment by liver dialysis and administration of steroids led to rapidly defervescence and clinical improvement. However, liver enzymes were still markedly elevated with persistent anemia, even after immunosuppressive treatment. The patient is currently waiting for liver transplantation. This is the first description of vanishing bile duct syndrome combined with hemophagocytic lymphohistiocytosis, with underlying causes including infection, drug-induced factors and untreated autoimmune disorder.

Naproxen-induced liver injury

BACKGROUND

Nonsteroidal anti-inflammatory drugs (NSAIDs) have been reported to induce liver injury. Patterns of the injury usually range from mild elevations of liver enzymes to sometimes severe fulminant hepatic failure. Likewise, naproxen is a propionic acid derivative NSAID that was introduced in 1980 and has been available as an over-the-counter medication since 1994, but has rarely been reported to cause liver injury.

METHODS

We treated a 30-year-old woman with jaundice and intractable pruritus that developed shortly after taking naproxen. We reviewed the medical history and liver histopathology of the patient as well as all previously published case reports of naproxen-associated liver toxicity in the English language literature.

RESULTS

The liver biochemical profile of the patient revealed a mixed cholestasis and hepatitis pattern. Consecutive liver biopsies demonstrated focal lobular inflammation, hepatocyte drop-out, and a progressive loss of the small interlobular bile ducts (ductopenia). The biopsy performed two years after onset of the disease showed partial recovery of a small number of bile ducts; however, 10 years passed before the biochemical profile returned to near normal.

CONCLUSIONS

Naproxen-associated liver toxicity remains a rare entity, but should be considered in any patient presenting with cholestasis shortly after its use. Liver injury is most commonly seen in a mixed pattern characterized by cholestasis and hepatitis. The resulting liver damage may take years to resolve.

Drug-induced cholestasis

Recent progress in understanding the molecular mechanisms of bile formation and cholestasis have led to new insights into the pathogenesis of drug-induced cholestasis. This review summarizes their variable clinical presentations, examines the role of transport proteins in hepatic drug clearance and toxicity, and addresses the increasing importance of genetic determinants, as well as practical aspects of diagnosis and management.

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

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

Human drug hepatotoxicity: a contemporary clinical perspective

BACKGROUND

Drug-induced liver injury (DILI) constitutes a significant medical challenge. The rising number of marketed drugs, aging population and polypharmacy make it imperative to understand the clinical presentation of DILI and the processes used in the assessment of causality and early detection.

OBJECTIVE

This article reviews the current clinical understanding of DILI including presentation patterns, causality assessment, risk factor ascertainment and early detection strategies including liver test monitoring. Significant initiatives such as the Drug-Induced Liver Injury Network (DILIN) are also discussed.

METHODS

A narrative review of clinical studies of DILI, with emphasis on clinical features, causality and surveillance.

CONCLUSION

DILI remains a serious challenge in contemporary clinical practice. Further research and collaboration in the areas of epidemiology, causality and early detection are required to enhance the diagnosis and management of DILI.

Genetic polymorphisms inGSTM1,GSTT1,GSTP1,GSTM3and the susceptibility to gallbladder cancer in North India

The glutathione S-transferase (GSTs) are polymorphic supergene family of detoxification enzymes that are involved in the metabolism of numerous potential carcinogens. Several allelic variants of polymorphic GSTs show impaired enzyme activity and are suspected to increase the susceptibility to various cancers. To find out the association of GST variants with risk of gallbladder cancer, the distribution of polymorphisms in the GST family of genes (GSTT1, GSTM1, GSTP1, and GSTM3) were studied in 106 cancer patients and 201 healthy controls. Genotypes were analysed by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP). The frequencies of GSTM1 null and GSTM3*BB genotypes did not differ between patients and controls. The overall frequency of GSTT1 null was lower in cases as compared with controls (p=0.003, Odds ratio (OR) = 0.2, 95% confidence interval (CI), 0.1-0.6). After sex stratification, the GSTT1 null frequency was reduced only in female patients (p=0.008, OR = 0.2, 95% CI = 0.1-0.6). However, the GSTP1, ile/val genotype and the val allele were significantly higher in cases than controls (p=0.013, OR = 1.9, 95% CI = 1.1-3.1; p=0.027, OR = 1.5, 95% CI = 1.0-2.1), respectively. To study gene-gene interactions, a combined risk of gallbladder cancer due to ile/val or val/val were calculated in combination with null alleles of GSTM1 and GSTT1 or the *B allele of GSTM3, but there was no enhancement of risk. Gallstones were present in 57.5% of patients with gallbladder cancer, but there were no significant differences between allelic/genotype frequencies of the studied GST genes polymorphisms between patients with or without gallstones. To best of our knowledge, this is the first paper showing ile/val genotypes and val allele of GSTP1 to be associated with higher risk of gallbladder cancer.

Association of CYP1A1 Msp1 polymorphism with tobacco-related risk of gallbladder cancer in a north Indian population

Polymorphisms in the gene encoding the metabolic enzyme cytochrome P450 1A1 (CYP1A1) might contribute to the variability in individual susceptibility to gallbladder cancer (GBC). This study comprised 142 consecutive cases of proven GBC and 171 healthy participants of similar ethnicity. CYP1A1 6235 T/C transition was analyzed using polymerase chain reaction-restriction fragment length polymorphism. The CC genotype of CYP1A1 was significantly associated with a risk of GBC [odds ratio (OR) 2.3, 95% confidence interval (CI)=1.1-4.5, P=0.026], and the age- and sex-adjusted OR was 2.0. The CYP1A1 C allele frequency was also higher in GBC patients (OR 1.4, 95% CI=1.0-2.0, P=0.039). After sex stratification, the TC genotype and C allele were significantly higher in men and conferred a risk for GBC (OR 4.2, 95% CI=1.8-9.7, P=0.001; OR 2.2, CI=1.3-3.7, P=0.005). In addition, the TC genotype and C allele frequencies were significantly higher in GBC patients without associated gallstones (OR 2.4, 95% CI=1.2-4.7, P=0.011; OR 1.6, CI=1.0-2.4, P=0.023). The usage of tobacco (smoking or nonsmoking) by GBC patients showed a significant increase in cancer risk with the TC genotype (OR 4.1, 95% CI=1.3-11.9, P=0.012). It seems that the higher risk of the TC genotype in men may be related to tobacco usage.

Mycophenolate mofetil for drug-induced vanishing bile duct syndrome

Amoxicillin/clavulanate is associated with liver injury, mostly of a cholestatic pattern. While outcomes are usually benign, progression to cirrhosis and death has been reported. The role of immunosuppressive therapy for patients with a protracted course is unclear. We report the case of an elderly patient who developed prolonged cholestasis secondary to amoxicillin/clavulanate. Vanishing bile duct syndrome was confirmed by sequential liver biopsies. The patient responded to prednisone treatment, but could not be weaned off corticosteroids, even when azathioprine was added. Complete withdrawal of both prednisone and azathioprine was possible by using mycophenolate mofetil, an inosine monophosphate dehydrogenase inhibitor. Sustained remission has been maintained for more than 3 years with low-dose mycophenolate mofetil.

Idiosyncratic drug-induced liver injury: an overview

Drug-induced liver injury (DILI) encompasses a spectrum of clinical disease ranging from mild biochemical abnormalities to acute liver failure. The majority of adverse liver reactions are idiosyncratic, occurring in most instances 5-90 days after the causative medication was last taken. The diagnosis of DILI is clinical, based on history, probability of the suspect medication as a cause of liver injury and exclusion of other hepatic disease. DILI can be hepatocellular (predominant rise in alanine transaminase), cholestatic (predominant rise in alkaline phosphatase) or mixed liver injury. An elevated bilirubin level more than twice the upper limit of normal in patients with hepatocellular liver injury implies severe DILI, with a mortality of approximately 10% and with an incidence rate of 0.7-1.3 per 100,000. Although acute liver failure is rare, 13-17% of all acute liver failure cases are attributed to idiosyncratic drug reactions. Response to drug withdrawal may be delayed up to 1 year with cholestatic liver injury with occasional subsequent progressive cholestasis known as the vanishing bile duct syndrome. Overall, chronic disease may occur in up to 6% even if the offending drug is withdrawn. Antibiotics and NSAIDs are the most common cause of DILI. Statins rarely cause significant liver injury whereas antiretroviral therapy is associated with hepatotoxicity in 10% of treated patients. Multiple mechanisms of DILI have been implicated, including TNF-alpha-activated apoptosis, inhibition of mitochondrial function and neoantigen formation. Risk factors for DILI include age, sex and genetic polymorphisms of drug-metabolising enzymes such as cytochrome P450. In patients with human immunodeficiency virus, the presence of chronic viral hepatitis increases the risk of antiretroviral therapy hepatotoxicity. Over the next decade, the combination of accurate case ascertainment of DILI via clinical networks and the application of genomics and proteomics will hopefully lead to accurate prediction of risk of DILI, so that pharmacotherapy can be optimised with avoidance of adverse hepatic events.

Drug-induced liver injury

Drug-induced liver injury is a frequent cause of hepatic dysfunction. Reliably establishing whether the liver disease was caused by a drug requires the exclusion of other plausible causes and the search for a clinical drug signature. The drug signature consists of the pattern of liver test abnormality, the duration of latency to symptomatic presentation, the presence or absence of immune-mediated hypersensitivity and the response to drug withdrawal. Determination of causality also includes an evaluation of individual susceptibility to drug-induced liver injury. This susceptibility is governed by both genetic and environmental factors. Components of the drug signature in conjunction with certain risk factors have been incorporated into formal scoring systems that are predictive of the likelihood of drug-induced liver injury. The most validated scoring system is the Roussel-Uclaf causality assessment method, which nonetheless retains certain imperfections. Mitigating the potential for drug-induced liver injury is achieved by the identification of toxicity signals during clinical trials and the monitoring of liver tests in clinical practice. There are three signals of liver toxicity in clinical trials: (i) a statistically significant doubling (or more) in the incidence of serum alanine aminotransferase (ALT) elevation >3 x the upper limit of normal (ULN); (ii) any incidence of serum ALT elevation >8-10 x ULN; and (iii) any incidence of serum ALT elevation >3 x ULN accompanied by a serum bilirubin elevation >2 x ULN. Monitoring of liver tests in clinical practice has shown unconvincing efficacy, but where a benefit-risk analysis would favour continued therapy, monthly monitoring may have some benefit compared with no monitoring at all. With rare exception, treatment of drug-induced liver injury is principally supportive. Drug toxicity is the most common cause of acute liver failure, defined as a prolonged prothrombin time (international normalised ratio > or =1.5) and any degree of mental alteration occurring <26 weeks after the onset of illness in a patient without pre-existing cirrhosis. A patient who meets these criteria must be evaluated for liver transplantation. The pathogenesis of drug-induced liver injury can be examined on the basis of the two principal patterns of injury. The hepatocellular pattern is characterised by a predominant rise in the level of transaminases and results from the demise of hepatocytes by means of either apoptosis or necrosis. The cholestatic pattern is characterised by a predominant rise of the serum alkaline phosphatase level and usually results from injury to the bile ductular cells either directly by the drug or its metabolite, or indirectly by an adaptive immune response.

Clinical and pathological features of a prolonged type of acute intrahepatic cholestasis

AIM

We examined the clinical and pathological features of drug-induced acute intrahepatic cholestasis (AIC) to elucidate the pathogenesis of prolonged cases.

METHODS

Twenty-six cases of drug-induced AIC were divided into prolonged and non-prolonged groups. Serum bilirubin levels and other biochemical data were compared between the two groups. Biopsy liver specimens were examined by light and electron microscopy. The localization of multidrug resistance protein 2 (MRP2) was immunohistochemically assessed by the Envision technique.

RESULTS

The causative drugs of four prolonged cases were found to be tiopronin, chlorpromazine and diclofenac. Two of the patients either died or underwent liver transplantation. The maximal total bilirubin levels (35.2 +/-> 13.8 mg/dL) were significantly higher and a half-life of total bilirubin (78.8 +/-> 69.6 days) was markedly longer in the prolonged cases, in comparison to the non-prolonged cases (16.8 +/-> 8.1 mg/dL, 22.1 +/-> 12.7 days, respectively). The liverbiopsy specimens revealed canalicular cholestasis and a slight degree of lobular inflammation. In the prolonged cases, liver cell injury and cholestasis was marked, and the interlobular bile ducts disappeared in the portal triads. The reaction products of MRP2, recognized on the bile canaliculi in a control liver, were weakened and found in the pericanalicular vesicles in AIC.

CONCLUSION

These results indicated disturbances in the canalicular bilirubin transport through MRP2 in the prolonged cases, resulting from severe cholestasis, liver cell injury and vanishing bile ducts. The histological findings of the liver at the acute icteric phase may be important to understand the pathogenesis and to predict the prognosis in AIC.

Protective effect of glycyrrhizin and matrine on acute vanishing bile duct syndrome induced by alpha-naphthylisothiocyanate in rats

AIM

To explore the effects of glycyrrhizin (GL) and matrine (MT) on acute vanishing bile duct syndromes (AVBDS) in rats.

METHODS

AVBDS in rats were induced by alphanaphthylisothiocyanate (ANIT), and the effects of GL and MT on AVBDS were explored and compared with dexamethasone (DEX) by serology determination, histological assessment of liver damage and bile excretion experiments.

RESULTS

The protection of DEX pre-treatment was directed toward cholangiocytes rather than hepatocytes. Rats remedially treated with DEX 3 h after ANIT were not resistant to ANIT toxicity. Notably, remedial treatment with DEX 12 h after ANIT enhanced ANIT toxicity. However, GL and MT attenuated both bile duct and hepatocyte damage induced by ANIT in the initial phase of impairment.

CONCLUSION

The nature products (GL and MT) exhibited better protection against ANIT-induced AVBDS than DEX. In the initial phase of impairment of AVBDS, the protection of GL and MT may be due partially to modifying the metabolism and excretion of ANIT and to their anti-inflammatory effects.

Assessment of drug-induced hepatotoxicity in clinical practice: a challenge for gastroenterologists

Currently, pharmaceutical preparations are serious contributors to liver disease; hepatotoxicity ranking as the most frequent cause for acute liver failure and post-commercialization regulatory decisions. The diagnosis of hepatotoxicity remains a difficult task because of the lack of reliable markers for use in general clinical practice. To incriminate any given drug in an episode of liver dysfunction is a step-by-step process that requires a high degree of suspicion, compatible chronology, 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 favors a toxic etiology. This process is time-consuming and the final result is frequently inaccurate. Diagnostic algorithms may add consistency to the diagnostic process by translating the suspicion into a quantitative score. Such scales are useful since they provide a framework that emphasizes the features that merit attention in cases of suspected hepatic adverse reaction as well. Current efforts in collecting bona fide cases of drug-induced hepatotoxicity will make refinements of existing scales feasible. It is now relatively easy to accommodate relevant data within the scoring system and to delete low-impact items. Efforts should also be directed toward the development of an abridged instrument for use in evaluating suspected drug-induced hepatotoxicity at the very beginning of the diagnosis and treatment process when clinical decisions need to be made. The instrument chosen would enable a confident diagnosis to be made on admission of the patient and treatment to be fine-tuned as further information is collected.

Restoration of bile ducts in drug-induced vanishing bile duct syndrome due to zonisamide

Prolonged drug-induced cholestasis may be due to destruction and disappearance of bile ducts, sometimes referred to as vanishing bile duct syndrome. Although some of these cases progress to fibrosis, cirrhosis, and liver failure, others improve with time. We report a case of a 35-year-old man who developed vanishing bile duct syndrome after ingestion of zonisamide, an antiepileptic drug that is also prescribed for weight loss. His liver biopsy showed complete absence of bile ducts 3 weeks after starting treatment. There was no ductular reaction. The drug was stopped and a follow-up biopsy 3 months later showed strands of intermediate hepatobiliary cells at the periphery of the portal tracts that extended into lobules; these structures lacked lumina and expressed biliary cytokeratins, CK7 and CK19. A third biopsy, 7 months later, showed the presence of ductules with lumina located within portal tracts. Intermediate hepatobiliary cells were rare; although sparse clusters of hepatocytes with membrane staining for CK7 were present. Cholestasis and levels of bilirubin improved over time. The histologic features in this case document the sequence of events in restoration of the biliary tree after loss of bile ducts, which seems to be a process of maturation of intermediate hepatobiliary cells that arise from a proliferative compartment at the porto-hepatic interface.

Prolonged cholestasis associated with short-term use of celecoxib

Drug-induced liver injury due to celecoxib, a first generation Cox-2 inhibitor, has been rarely reported. We describe one case of severe and prolonged cholestasis after treatment with celecoxib for 12 days in a young woman with no evidence of other causes of liver disease or allergy. Jaundice lasted for 3 months, pruritus and abnormal liver biochemistry persisted for 18 months after stopping the drug. Liver biopsy specimens showed a cholestatic pattern of liver injury with only minimal mononuclear infiltrate in the portal tracts. This case report supports the notion that celecoxib may cause bland, long term cholestasis.

Vanishing bile duct syndrome in a child with toxic epidermal necrolysis: an interplay of unbalanced immune regulatory mechanisms

Vanishing bile duct syndrome (VBDS) is a rare disorder and requires a liver biopsy for a diagnosis. The condition has not been reported in children with toxic epidermal necrolysis (TEN). The etiology of VBDS in our patient with TEN is most likely from drug hypersensitivity. A high index of suspicion will prompt clinicians to start more specific investigations and treatments. The use of immunosuppressive agents, intravenous immunoglobulin and ursodeoxycholic acid has not been consistently successful in these patients. A new approach with biologic agents such as anti-tumor necrosis factor-alpha may be a promising therapy and reduce severe adverse outcomes.

Drug-induced liver injury: summary of a single topic clinical research conference

Idiosyncratic drug induced liver injury (DILI) remains poorly understood. It is assumed that the affected individuals possess a rare combination of genetic and non genetic factors that, if identified, would greatly improve understanding of the underlying mechanisms. This single topic conference brought together basic scientists, translational investigators, and clinicians with an interest in DILI. The goal was to define high priority areas of investigation that will soon be made possible by The Drug-Induced Liver Injury Network (DILIN). Since 2004 DILIN has been collecting clinical data, genomic DNA and some tissues from patients who have experienced bone fide DILI. The presentations spanned many different areas of DILI, and included novel data concerning mechanisms of hepatotoxicity, new "omics" approaches, and the challenges of improving causation assessment.

[Ductal regeneration in vanishing bile duct syndrome in Hodgkin's lymphoma]

We present the case of a 17-year-old male patient with Hodgkin's lymphoma (nodular sclerosis) in the mediastinum. During the postoperative period treatment with erythromycin was started and the patient developed progressive jaundice and cholestasis. Treatment modified for the lymphoma was initiated, which achieved complete remission and subsequent improvement and resolution of the cholestasis. Histological study of the liver revealed massive loss of bile ducts. After resolution of the cholestasis, consecutive biopsies revealed ductal proliferation. The present report therefore illustrates a case of ductopenia or vanishing bile duct syndrome (VBDS) with ad integrum regeneration of the bile ducts simultaneous with lymphoma remission. Because the 2 possible causes, erythromycin toxicity and Hodgkin's lymphoma, occurred simultaneously, the etiology of the VBDS cannot be definitively established.

Sclerosing cholangitis following severe trauma: Description of a remarkable disease entity with emphasis on possible pathophysiologic mechanisms

AIM: Persistent cholestasis is a rare complication of severe trauma or infections. Little is known about the possible pathomechanisms and the clinical course.

METHODS: Secondary sclerosing cholangitis was diagnosed in five patients with persistent jaundice after severe trauma (one burn injury, three accidents, one power current injury). Medical charts were retrospectively reviewed with regard to possible trigger mechanisms for cholestasis, and the clinical course was recorded.

RESULTS: Diagnosis of secondary sclerosing cholangitis was based in all patients on the primary sclerosing cholangitis (PSC)-like destruction of the intrahepatic bile ducts at cholangiography after exclusion of PSC. In four patients, arterial hypotension with subsequent ischemia may have caused the bile duct damage, whereas in the case of power current injury direct thermal damage was assumed to be the trigger mechanism. The course of secondary liver fibrosis was rapidly progressive and proceeded to liver cirrhosis in all four patients with a follow-up >2 years. Therapeutic possibilities were limited.

CONCLUSION: Posttraumatic sclerosing cholangitis is a rare but rapidly progressive disease, probably caused by ischemia of the intrahepatic bile ducts via the peribiliary capillary plexus due to arterial hypotension. Gastroenterologists should be aware of this disease in patients with persistent cholestasis after severe trauma.

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.

Probable sulbactam/ampicillin-associated prolonged cholestasis

OBJECTIVE

To present a single case of sulbactam/ampicillin-induced chronic cholestasis and a literature review of antibiotic-associated chronic cholestasis.

CASE SUMMARY

A 74-year-old man with Hodgkin's disease in remission developed severe and prolonged cholestasis after treatment with sulbactam/ampicillin 750 mg twice daily for 7 days. All other etiologies, including Hodgkin's disease, were appropriately ruled out and the cholestasis was ascribed to sulbactam/ampicillin treatment. The patient improved gradually and became asymptomatic 7 months after the last dose of sulbactam/ampicillin. According to the Naranjo probability scale, sulbactam/ampicillin was the probable cause of the cholestasis.

DISCUSSION

Ampicillin, a semisynthetic penicillin, has rarely been associated with hepatic injury when used alone. Hepatocellular and acute cholestatic injury due to ampicillin have been described. Cholestasis secondary to sulbactam/ampicillin use has not been previously reported.

CONCLUSIONS

Sulbactam/ampicillin, one of the most widely used antibiotics, may cause chronic cholestatic hepatitis. Clinicians should be aware of this adverse affect and consider it during diagnostic workup of liver injury.