A. Castiella

Glutathione S-transferase m1 and t1 null genotypes increase susceptibility to idiosyncratic drug-induced liver injury.

Individual vulnerability to drug‐induced liver injury (DILI) might result from deficiencies in the detoxification process, which determines the level of exposure to the reactive metabolite. We evaluated whether a genetically determined reduction in the ability to detoxify electrophilic compounds, such as that expected among individuals with glutathione S‐transferase (GST) null genotypes, might play a role in determining the risk for DILI and its clinical expression. Genomic DNA from 154 patients (74 men, 80 women; mean age, 53 years) with a diagnosis of DILI as assessed with the Council for International Organizations of Medical Science scale and 250 sex‐ and age‐matched healthy controls were analyzed. A multiplex polymerase chain reaction–based method was used to detect GSTM1 and GSTT1 gene deletions. Carriers of double GSTT1‐M1 null genotypes had a 2.70‐fold increased risk of developing DILI compared with noncarriers (odds ratio 2.70, 95% confidence interval 1.45‐5.03; P = 0.003). The odds ratio for DILI patients receiving antibacterials, and NSAIDs were 3.52 (P = 0.002), and 5.61 (P = 0.001), respectively. Patients with amoxicillin‐clavulanate hepatotoxicity (n = 32) had a 2.81‐fold increased risk (P = 0.037). Patients classified by the combined GSTT1 and GSTM1 null genotypes did not differ with regard to the type of injury, clinical presentation, or outcome, except for the predominance of women in the combined null genotype (P < 0.001). Conclusion: The double‐null genotype for GSTT1 and GSTM1 might play a role in determining the susceptibility to develop DILI, as a general mechanism that occurs regardless of the type of drug involved, and predominantly in women. (HEPATOLOGY 2008;48:588–596.)

Determinants of the clinical expression of amoxicillin-clavulanate hepatotoxicity: A prospective series from Spain†‡

Amoxicillin‐clavulanate (AC) hepatotoxicity has been reported to exhibit a higher predominance of cholestatic types of damage, especially in males. However, the determinants of its clinical expression are unknown. This study prospectively evaluated the profile of AC hepatotoxicity. Data on all cases of hepatotoxicity reported to the Spanish Registry attributed to AC and assessed as definite or probable on the Council for International Organizations of Medical Sciences (CIOMS) scale were collated and compared to published case series. Hepatotoxicity related to amoxicillin‐clavulanate was identified in 69 patients (36 males; mean age 56 years) representing 14% of all cases of hepatotoxicity submitted to the Registry. There was an overall sex distribution and the predominant pattern of lesion was hepatocellular (36%) which occurred at a shorter duration of treatment (P < .03). Mean time lapse between therapy initiation and jaundice onset was 16 days. Late onset of symptoms following end of treatment occurred in half the cases. Multiple logistic regression analysis identified advancing age as the factor associated with the development of cholestatic/mixed type of injury (odds ratio for an age interval for 1 year: 1.045 [95% CI = 1.013–1.078; P = .005). An unfavorable outcome was seen in 7% of patients. In conclusion, age is the most important determinant in the biochemical expression of AC hepatotoxicity; younger age is associated with cytolytic damage and shorter treatment duration, whereas cholestatic/mixed type of damage is related to older age and prolonged AC therapy. (HEPATOLOGY 2006;44:850–856.)

Recurrent Drug-Induced Liver Injury (DILI) with different drugs in the Spanish Registry: The dilemma of the relationship to autoimmune hepatitis

BACKGROUND & AIMSnMultiple instances of DILI in the same patient with drugs of similar structure or function as well as completely unrelated drugs are not well understood and poorly documented. We have sought evidence of the frequency and characteristics of patients who have experienced two DILI episodes due to different drugs.nnnMETHODSnAll cases of DILI systematically collected in the Spanish DILI Registry between 1994 and 2009 were retrieved. Data on demographics, clinical, laboratory and pathological findings, and outcome were analyzed.nnnRESULTSnNine patients (mean age 67 years, four women) out of 742, 1.21%, had evidence of two DILI episodes caused by different drugs. In four cases DILI was associated with structurally related drugs and in an additional two cases the drugs had a common target. In another case, unrelated antibiotics were implicated. In only two cases, the two drugs/herbals were not related in structure or function. All but one patient exhibited hepatocellular damage. The type of damage was consistent in both DILI episodes. Four cases presented as autoimmune hepatitis (AIH) in the second episode.nnnCONCLUSIONSnMultiple episodes of DILI in association with different drugs occur infrequently. In each individual, the type of injury was similar during the two DILI episodes, regardless of the causative drug. Second episodes of DILI are more likely to be associated with features of AIH. It remains uncertain if this is drug-induced unmasking of true AIH or DILI with autoimmune features. These cases illustrate the dilemma faced by clinicians in distinguishing these possibilities.

drug-induced autoimmune liver disease: a diagnostic dilemma of an increasingly reported disease

The aetiology of autoimmune hepatitis (AIH) is uncertain but the disease can be triggered in susceptible patients by external factors such as viruses or drugs. AIH usually develops in individuals with a genetic background mainly consisting of some risk alleles of the major histocompatibility complex (HLA). Many drugs have been linked to AIH phenotypes, which sometimes persist after drug discontinuation, suggesting that they awaken latent autoimmunity. At least three clinical scenarios have been proposed that refers to drug- induced autoimmune liver disease (DIAILD): AIH with drug-induced liver injury (DILI); drug induced-AIH (DI-AIH); and immune mediated DILI (IM-DILI). In addition, there are instances showing mixed features of DI-AIH and IM-DILI, as well as DILI cases with positive autoantibodies. Histologically distinguishing DILI from AIH remains a challenge. Even more challenging is the differentiation of AIH from DI-AIH mainly relying in histological features; however, a detailed standardised histologic evaluation of large cohorts of AIH and DI-AIH patients would probably render more subtle features that could be of help in the differential diagnosis between both entities. Growing information on the relationship of drugs and AIH is being available, being drugs like statins and biologic agents more frequently involved in cases of DIAILD. In addition, there is some evidence on the fact that patients diagnosed with DIAILD may have had a previous episode of hepatotoxicity. Further collaborative studies in DIAILD will strengthen the knowledge and understanding of this intriguing and complex disorder which might represent different phenotypes across the spectrum of disease.

Definition and risk factors for chronicity following acute idiosyncratic drug-induced liver injury

BACKGROUND & AIMSnChronic outcome following acute idiosyncratic drug-induced liver injury (DILI) is not yet defined. This prospective, long-term follow-up study aimed to analyze time to liver enzyme resolutions to establish the best definition and risk factors of DILI chronicity.nnnMETHODSn298 out of 850 patients in the Spanish DILI registry with no pre-existing disease affecting the liver and follow-up to resolution or ⩾1year were analyzed. Chronicity was defined as abnormal liver biochemistry, imaging test or histology one year after DILI recognition.nnnRESULTSnOut of 298 patients enrolled 273 (92%) resolved ⩽1year from DILI recognition and 25 patients (8%) were chronic. Independent risk factors for chronicity were older age [OR: 1.06, p=0.011], dyslipidemia [OR: 4.26, p=0.04] and severe DILI [OR: 14.22, p=0.005]. Alanine aminotransferase (ALT), alkaline phosphatase (ALP) and total bilirubin (TB) median values were higher in the chronic group during follow-up. Values of ALP and TB >1.1 x upper limit of normal (xULN) and 2.8 xULN respectively, in the second month from DILI onset, were found to predict chronic DILI (p<0.001). Main drug classes involved in chronicity were statins (24%) and anti-infectives (24%). Histological examination in chronic patients demonstrated two cases with ductal lesion and seven with cirrhosis.nnnCONCLUSIONSnOne year is the best cut-off point to define chronic DILI or prolonged recovery, with risk factors being older age, dyslipidemia and severity of the acute episode. Statins are distinctly related to chronicity. ALP and TB values in the second month could help predict chronicity or very prolonged recovery.nnnLAY SUMMARYnDrug-induced liver injury (DILI) patients who do not resolve their liver damage during the first year should be considered chronic DILI patients. Risk factors for DILI chronicity are older age, dyslipidemia and severity of the acute episode. Chronic DILI is not a very common condition; normally featuring mild liver profile abnormalities and not being an important clinical problem, with the exception of a small number of cases of early onset cirrhosis.

The value of serum aspartate aminotransferase and gamma‐glutamyl transpetidase as biomarkers in hepatotoxicity

The current definition of the pattern of liver injury in hepatotoxicity (DILI) is given by the R (ratio) value, dividing alanine aminotransferase (ALT) and alkaline phosphatase (ALP) in upper limits of normal at DILI onset. We aimed to explore the validity of using aspartate aminotransferase (AST) and gamma‐glutamyl transpeptidase (GGT) as biomarkers of hepatocelullar and cholestatic damage, respectively, when calculating the R value.

Drug-Induced Autoimmune-Like Hepatitis: A Diagnostic Challenge

Dear Editor,We have read with interest the excellent review byCzaja [1] titled ‘‘Drug-Induced Autoimmune-Like Hepati-tis’’. We would like to add some comments to highlight thecomplexities faced when approaching a diagnosis of thisdisorder.Firstly, it is stated under the subheading ‘‘Drug-InducedHepatitis Within the Spectrum of Immune-Mediated Hep-atitis’’ that the best estimate of the frequency of drug-induced autoimmune-like hepatitis (AIH-DILI) amongpatients with classical features of autoimmune hepatitis is9% [2]. To our knowledge, there are other reports thatshow higher figures. Heurgue´ et al. [3] in France identifiedin a consecutive series of 65 patients with autoimmunehepatitis (AIH) eight cases (12%) with drug-induced AIH,fulfilling all requirements recommended in the review toconfirm the diagnosis. In Gipuzkoa (Deba Valley, totalcatchment of 140,000 people), Spain, from 1994 to 2009,29 cases of AIH were diagnosed, and five were consideredas AIH-DILI, which represents 17% [4]. We think thatthese differences in frequency may be explained by the factthat AIH-DILI is often misdiagnosed. Indeed, the diagnosisof AIH is often made in the setting of a patient beingtreated with multiple drugs. If the diagnostic scale indicatesa probable AIH, the possible role of the drug is generallyunderscored, and immunosuppressive treatment is started.On the other hand, if the AIH scale is not conclusive and/orhistology findings are more consistent with drug-inducedliver injury (DILI), the case is assumed to be an AIH-DILIcase, particularly if after discontinuation of the suspecteddrug the clinical symptoms resolve (AIH-DILI may be aself-limiting process), and the possibility of unmaskingAIH by the action of a drug is subsequently disregarded. Tofurther complicate the differentiation between AIH andDILI, we must underline the fact that there does not seemto be any specific histological features for either of theprocesses and the pathological features may show onlysubtle differences, pointing toward an immune mediatesliver disease versus hepatic toxicity [5]. These consider-ations lead us to suggest that AIH-DILI might be under-reported nowadays.Secondly, it is said that most drugs produce a self-lim-ited acute hepatitis, which is unusual in true AIH [1], butthat others seem to trigger a chronic hepatitis that isindistinguishable from classical AIH. In a recent study,Bjo¨rnsson et al. [2] published 24 cases of AIH-DILI, 22being minocycline and nitrofurantoin cases (11/11). Dis-continuation of steroid therapy was tried in 14 cases, withno relapses. Of the AIH cases in this series, 65% relapsed.In a French series [3], one patient had a spontaneous

Herbal and Dietary Supplement-Induced Liver Injuries in the Spanish DILI Registry

Background & Aims There have been increasing reports of liver injury associated with use of herbal and dietary supplements, likely due to easy access to these products and beliefs among consumers that they are safer or more effective than conventional medications. We aimed to evaluate clinical features and outcomes of patients with herbal and dietary supplement‐induced liver injuries included in the Spanish DILI Registry. Methods We collected and analyzed data on demographic and clinical features, along with biochemical parameters, of 32 patients with herbal and dietary supplement‐associated liver injury reported to the Spanish DILI registry from 1994 through 2016. We used analysis of variance to compare these data with those from cases of liver injury induced by conventional drugs or anabolic androgenic steroid‐containing products. Results Herbal and dietary supplements were responsible for 4% (32 cases) of the 856 DILI cases in the registry; 20 cases of DILI (2%) were caused by anabolic androgenic steroids. Patients with herbal and dietary supplement‐induced liver injury were a mean age of 48 years and 63% were female; they presented a mean level of alanine aminotransferase 37‐fold the upper limit of normal, 28% had hypersensitivity features, and 78% had jaundice. Herbal and dietary supplement‐induced liver injury progressed to acute liver failure in 6% of patients, compared with none of the cases of anabolic androgenic steroid‐induced injury and 4% of cases of conventional drugs. Liver injury after repeat exposure to the same product that caused the first DILI episode occurred in 9% of patients with herbal and dietary supplement‐induced liver injury vs none of the patients with anabolic androgenic steroid‐induced injury and 6% of patients with liver injury from conventional drugs. Conclusion In an analysis of cases of herbal and dietary supplement‐induced liver injury in Spain, we found cases to be more frequent among young women than older patients or men, and to associate with hepatocellular injury and high levels of transaminases. Herbal and dietary supplement‐induced liver injury is more severe than other types of DILI and re‐exposure is more likely. Increasing awareness of the hepatoxic effects of herbal and dietary supplements could help physicians make earlier diagnoses and reduce the risk of serious liver damage.

P1097 : Distinguishing drug induced autoimmune hepatitis from idiopatic autoimmune hepatitis

M30/CK18-cleavage staining, indicators of hepatocyte apoptosis. Indicators of oxidative stress, including the accumulation of 4-HNEprotein adducts and JNK phosphorylation, were also increased. In contrast, mice deficient in MLK3 were protected from ethanolinduced increases in plasma ALT/AST, pro-inflammatory cytokines and hepatic protein expression of RIP3. Ethanol-induced JNK phosphorylation and oxidative stress were also attenuated in MLK3deficient mice. However, MLK3-deficiency did not affect ethanolinduced steatosis or hepatocyte apoptosis. Conclusions: Taken together, these results suggest that MLK3 participates in the development of ethanol-induced oxidative stress, activation of JNK and induction of necroptotic programmed hepatocyte death. Pharmacological intervention of this pathway could be targeted as a potential therapeutic strategy to suppress necroptosis-induced inflammation and hepatocyte injury in patients with ALD.

S1873 The use of Liver Biopsy Evaluation in Determination of Autoimmune Hepatitis vs. Drug-Induced Liver Injury

Background/Aims: There has been increased interest in the potential role of B cells and antimitochondrial antibodies in PBC. Indeed a new paradigm in PBC includes the potential of B cells to act as both regulatory elements and as components of the inflammasone induced by apoptosis of biliary cells. We submit that a rigorous dissection of the inflammatory infiltrate in PBC will provide further insight on these issues. Materials and Methods: We took advantage of well-characterized Mabs to CD3, CD4, CD8, CD20, CD38, CD56, CD68, and pan-keratin antigens, and immunohistochemistry (IHC), to study the distribution of liver infiltrating CD38-positive plasma cells in 26 consecutive patients with PBC (AMA positive in 20 and negative in 6), all of whom had detailed staged clinical data. All data was “blindly” evaluated. We simultaneously studied 10 ageand gender-matched patients with chronic hepatitis C as a control. Results: Noteworthy within the IHC data was the presence of an intense coronal arrangement (CR) of CD38-positive cells around interlobular bile ducts, generally in specimens with chronic non-suppurative destractive cholangitis (CNSDC). In contrast, CD20-positive B lymphocytes (precursor cells of plasma cells) were found scattered and/or aggregated within the lymphoplasmocytic infiltration. Such CD20positive B cells also occasionally formed follicle-like aggregations but importantly were not observed in the proximity of CNSDC. PBC patients with CR demonstrated significantly higher titers of AMA (119.5±16.1 vs. 59.7±17.1, p=0.018) and lower levels of total cholesterol (TC) (195.1±9.0 vs. 223.6±9.6, p=0.04) than those without CR. Interestingly the CR correlated with titer of AMA (r=0.46), IgM (r=0.32), the presence of CNSDC (r=0.32) and inversely with age (r=-0.37), γ-GTP (r=-0.38) and TC (r=-0.41). In contrast, CD4and CD8-positive T lymphocyte infiltration was noted either in proximity of, or within the degenerated cholangioepithelium, suggesting the participation of these cells in the destructive processes of interlobular bile ducts. No CR was found in control subjects. Conclusion: The presence of CD38+ plasma cells surrounding biliary epithelium has clinical and serologic significance; further it correlates with disease progression exemplified by TC decrease and the development of florid duct lesions. These data further highlight the functional significance of B cells/ plasma cells; it also reflects a multilineage loss of tolerance in PBC. We submit that study of B cells in PBC should go beyond simple measurement of AMA titer and include rigorous phenotypical and functional dissection of the liver specific B cell lineage populations.