Worldwide Use of RUCAM for Causality Assessment in 81,856 Idiosyncratic DILI and 14,029 HILI Cases Published 1993-Mid 2020: A Comprehensive Analysis

Drug-Induced Liver Injury: Highlights and Controversies in the Recent Literature

Drug-induced liver injury (DILI) remains an important, yet challenging diagnosis for physicians. Each year, additional drugs are implicated in DILI and this year was no different, with more than 1400 articles published on the subject. This review examines some of the most significant highlights and controversies in DILI-related research over the past year and their implications for clinical practice. Several new drugs were approved by the US Food and Drug Administration including a number of drugs implicated in causing DILI, particularly among the chemotherapeutic classes. The COVID-19 pandemic was also a major focus of attention in 2020 and we discuss some of the notable aspects of COVID-19-related liver injury and its implications for diagnosing DILI. Updates in diagnostic and causality assessments related to DILI such as the Roussel Uclaf Causality Assessment Method are included, mindful that there is still no single biomarker or diagnostic tool to unequivocally diagnose DILI. Glutamate dehydrogenase received renewed attention as being more specific than alanine aminotransferase. There were a few new reports of previously unrecognized hepatotoxins, including immune modulators and novel gene therapy drugs that we highlight. Updates and new developments of previously described hepatotoxins, such as immune checkpoint inhibitors and anti-tuberculosis drugs are reviewed. Finally, novel technologies such as organoid culture systems to better predict DILI preclinically may be coming of age and determinants of hepatocyte loss, such as calculating P_ALT are poised to improve our current means of estimating DILI severity and the risk of acute liver failure.

Herbal and dietary supplement-induced liver injury in Taiwan: comparison with conventional drug-induced liver injury

BACKGROUND AND AIMS

Whether herbal and dietary supplements (HDS) are safer than Western conventional drugs is controversial. The aim of this study was to explore the characteristics and risk factors for HDS-induced liver injury (HILI) in Taiwan.

METHODS

This is a 9-year multi-center prospective study conducted in Taiwan from 2011 to 2019. Patients with HILI were compared to those with conventional drug-induced liver injury (CILI).

RESULTS

A total of 1,297 patients were enrolled, of whom 285 (22.0%) had HILI and 1,012 (78.0%) had CILI. Compared to the CILI group, the HILI group had higher initial serum alanine aminotransferase, alkaline phosphatase (ALP), peak ALP and bilirubin levels, and higher rates of jaundice, ascites, encephalopathy, coagulopathy, sepsis and acute liver failure. In addition, the HILI group had a higher mortality rate than the CILI group (12.6 vs. 8.0%, p = 0.016). Hepatitis B carrier status, elevated baseline liver biochemical tests and the use of crude herbs (without processing) were associated with an increased risk of HILI-related mortality (adjusted hazard ratios [95% confidence intervals]: 2.90 [1.43-5.99], 2.40 [1.01-5.68] and 2.94 [1.45-5.97], respectively).

CONCLUSIONS

HDS are popular and incriminated in more than one-fifth of drug-induced liver injuries in Taiwan. The patients with HILI were more severe than those with CILI in terms of liver biochemical tests, complications and mortality. Hepatitis B carriers, those with elevated baseline liver tests and crude herb users may have a higher risk of HILI-related mortality. The prudent use of HDS is suggested in these high-risk subjects.

Circulatory Inflammatory Mediators in the Prediction of Anti-Tuberculous Drug-Induced Liver Injury Using RUCAM for Causality Assessment

BACKGROUND

Anti-tuberculous (TB) medications are common causes of drug-induced liver injury (DILI). Limited data are available on systemic inflammatory mediators as biomarkers for predicting DILI before treatment. We aimed to select predictive markers among potential candidates and to formulate a predictive model of DILI for TB patients.

METHODS

Adult active TB patients from a prospective cohort were enrolled, and all participants received standard anti-tuberculous treatment. Development of DILI, defined as ≥5× ULN for alanine transaminase or ≥2.6× ULN of total bilirubin with causality assessment (RUCAM, Roussel Uclaf causality assessment method), was regularly monitored. Pre-treatment plasma was assayed for 15 candidates, and a set of risk prediction scores was established using Cox regression and receiver-operating characteristic analyses.

RESULTS

A total of 19 (7.9%) in 240 patients developed DILI (including six carriers of hepatitis B virus) following anti-TB treatment. Interleukin (IL)-22 binding protein (BP), interferon gamma-induced protein 1 (IP-10), soluble CD163 (sCD163), IL-6, and CD206 were significant univariable factors associated with DILI development, and the former three were backward selected as multivariable factors, with adjusted hazards of 0.20 (0.07-0.58), 3.71 (1.35-10.21), and 3.28 (1.07-10.06), respectively. A score set composed of IL-22BP, IP-10, and sCD163 had an improved area under the curve of 0.744 (p < 0.001).

CONCLUSIONS

Pre-treatment IL-22BP was a protective biomarker against DILI development under anti-TB treatment, and a score set by additional risk factors of IP-10 and sCD163 employed an adequate DILI prediction.

Idiosyncratic Drug Induced Liver Injury, Cytochrome P450, Metabolic Risk Factors and Lipophilicity: Highlights and Controversies

Progress in understanding the mechanisms of the idiosyncratic drug induced liver injury (iDILI) was highlighted in a scientometric investigation on the knowledge mapping of iDILI throughout the world, but uncertainty remained on metabolic risk factors of iDILI, the focus of the present review article. For the first time, a quantitative analysis of 3312 cases of iDILI assessed for causality with RUCAM (Roussel Uclaf Causality Assessment Method) showed that most drugs (61.1%) were metabolized by cytochrome P450 (CYP) isoforms: 49.6% by CYP 3A4/5, 24.6% by CYP 2C9, 13.2% by CYP 2E1, 7.3% by CYP 2C19, 3.5% by CYP 1A2 and 1.8% by CYP 2D6. Other studies showed high OR (odds ratio) for drugs metabolized by unspecified CYPs but the iDILI cases were not assessed for causality with RUCAM, a major shortcoming. In addition to critical comments on methodological flaws, several risk factors of iDILI were identified such as high but yet recommended daily drug doses, actual daily drug doses taken by the patients, hepatic drug metabolism and drug lipophilicity. These risk factors are subject to controversies by many experts seen critically also by others who outlined that none of these medication characteristics is able to predict iDILI with high confidence, leading to the statement of an outstanding caveat. It was also argued that all previous studies lacked comprehensive data because the number of examined drugs was relatively small as compared to the number of approved new molecular entities or currently used oral prescription drugs. In conclusion, trends are evident that some metabolic parameters are likely risk factors of iDILI but strong evidence can only be achieved when methodological issues will be successfully met.

An update on the pharmacological management of autoimmune hepatitis

Introduction: Autoimmune hepatitis (AIH) is an immune mediated, inflammatory disease affecting the liver as a result of environmental triggers in susceptible individuals leading to loss of self-tolerance. The immunopathogenesis of AIH is not fully understood, which limits targeted therapeutic options.Areas covered: In this review, the authors provide an overview of current practice in the management of AIH, which include induction therapy with corticosteroids (± thiopurines), followed by maintenance therapy. Lack of early response to treatment may serve as a predictor of those at risk of requiring treatment escalation to second- and third-line agents such as mycophenolate mofetil (MMF), calcineurin inhibitors or biologics. Evidence for third-line agents from small retrospective studies or individual centers are reviewed. The nuances of AIH treatment in pregnancy, overlap syndromes, and drug induced liver injury (DILI) warrant further consideration.Expert opinion: Augmenting the balance of regulatory T cells (Treg) and effector T cells is an appealing therapeutic target with a multitude of agents in development. Many of the challenges in AIH research are due to its rarity and lack of randomized data. Management of AIH should strive towards individualized care through risk stratification and use of the best therapeutic modality for each patient.

Idiosyncratic Drug-Induced Liver Injury (DILI) and Herb-Induced Liver Injury (HILI): Diagnostic Algorithm Based on the Quantitative Roussel Uclaf Causality Assessment Method (RUCAM)

Causality assessment in liver injury induced by drugs and herbs remains a debated issue, requiring innovation and thorough understanding based on detailed information. Artificial intelligence (AI) principles recommend the use of algorithms for solving complex processes and are included in the diagnostic algorithm of Roussel Uclaf Causality Assessment Method (RUCAM) to help assess causality in suspected cases of idiosyncratic drug-induced liver injury (DILI) and herb-induced liver injury (HILI). From 1993 until the middle of 2020, a total of 95,865 DILI and HILI cases were assessed by RUCAM, outperforming by case numbers any other causality assessment method. The success of RUCAM can be traced back to its quantitative features with specific data elements that are individually scored leading to a final causality grading. RUCAM is objective, user friendly, transparent, and liver injury specific, with an updated version that should be used in future DILI and HILI cases. Support of RUCAM was also provided by scientists from China, not affiliated to any network, in the results of a scientometric evaluation of the global knowledge base of DILI. They highlighted the original RUCAM of 1993 and their authors as a publication quoted the greatest number of times and ranked first in the category of the top 10 references related to DILI. In conclusion, for stakeholders involved in DILI and HILI, RUCAM seems to be an effective diagnostic algorithm in line with AI principles.

Epidemiology of Drug- and Herb-Induced Liver Injury Assessed for Causality Using the Updated RUCAM in Two Hospitals from China

Drug- and herb-induced liver injury (DILI and HILI) is an increasingly common and serious condition. Here, data for DILI and HILI patients from two large tertiary hospitals were retrospectively analyzed. Patient characteristics, causes and severity of DILI and HILI, the correlation between expression of p62 and the severity of DILI and HILI, treatment of DILI and HILI, and the prognostic factors of DILI and HILI were studied. A total of 82 patients with DILI and HILI were recruited for the study. Most patients presented with hepatocellular injury, followed by cholestatic injury and mixed injury. Our results indicate that traditional Chinese medicine or herbal and dietary supplements were the prevalent causal agents of HILI, which was characterized by higher frequencies of hepatocellular injury. Expression of p62 in the liver correlated with the severity of DILI and HILI. Improvements in the results of the liver enzymatic tests correlated with alanine transaminase (ALT) levels upon the first diagnosis of DILI and HILI and with the hepatocellular type of DILI and HILI. In conclusion, we provide an epidemiological assessment of DILI and HILI based on causality using the updated RUCAM on patients from two hospitals in China. ALT levels at first diagnosis and the hepatocellular type of injury may be prognostic factors of DILI and HILI.

Safety of co-administration of herbal and conventional medicines on liver and kidney function in stroke patients: A single-center retrospective study

BACKGROUND

Although herbal medicines (HMs) are widely used worldwide, information concerning their interactions with conventional medicines (CMs) is sparse. In particular, stroke affects a high proportion of elderly people with impaired hepatic and renal function. Stroke is often accompanied by various complications and is commonly treated via the co-administration of HMs and CMs in Asia.

PURPOSE

We aimed to investigate the effects of co-administration of HMs and CMs on liver and kidney function in patients with stroke. We estimated the prevalence of drug-induced liver injury (DILI) or herb-induced liver injury (HILI) and drug-induced acute kidney injury (DIAKI) or herb-induced acute kidney injury (HIAKI) in patients co-administered HMs and CMs.

STUDY DESIGN

This was a retrospective study that reviewed the electronic medical records of 401 patients with stroke in a single hospital.

METHODS

The prevalence of DILI or HILI and types of liver injury was examined according to abnormal increases in liver tests. The probable causality between drug or herb administration and liver injury was assessed using the Roussel Uclaf Causality Assessment Method. In addition, the prevalence of DIAKI or HIAKI was estimated using the Kidney Disease Improving Global Outcomes acute kidney injury stage criteria and related medical records.

RESULTS

Out of a total of 401 patients, only four (1.0%) developed liver injury. Two cases of DILI (0.5%) and two cases of HILI (0.5%) were reported. Moxifloxacin and ebastine were the CMs that caused hepatotoxicity. Chungpyesagan-tang and Yeoldahanso-tang were the HMs that caused liver toxicity. Even in cases showing severe liver damage, alkaline phosphatase levels remained less than five times the normal value, and liver function test values recovered within 14 days. There were no cases of DIAKI or HIAKI in this cohort.

CONCLUSION

These results suggest that if appropriately prescribed by experts, the co-administration of CMs and HMs is safe and does not adversely affect liver and kidney function in patients with stroke. To support these results, further large-scale multicenter prospective studies and toxicological studies based on the interaction between HMs and CMs are warranted.

Appropriate chemopreventive strategy for anti-tubercular therapy related liver injury is unsettled: Results from a systematic review and network meta-analysis

BACKGROUND

Role of chemoprophylaxis for prevention of antitubercular therapy-related drug-induced liver injury (ATT-DILI) is uncertain.

METHODS

Electronic databases were searched for randomized trials reporting on chemoprophylaxis agents for prevention of ATT-DILI. We included studies evaluating the role of a drug in comparison to controls/placebo. The primary outcome was the occurrence of ATT-DILI. We performed a Bayesian random-effects network meta-analysis to calculate odds ratios (ORs) and 95% credible intervals (CrI) for those arms where at least two studies were available. Additional comparative studies for these arms were also identified.

RESULTS

Fourteen studies were identified and seven included in the meta-analysis. The agents used for prevention of ATT-DILI were silymarin/silibinin (4 trials), N-acetylcysteine (NAC) (3 studies), herbal preparations (5 studies) and one study each for cholecalciferol and carnitine. Compared with controls/placebo, the odds of occurrence of hepatotoxicity with NAC was 7 * 10-17 (95% CrI: 2.8 * 10-53, 0.0053) and Silymarin was 0.68 (95% CrI: 0.084, 4.6). NAC had the highest probability of rank 1 (0.99) which was followed by Silymarin (0.004).

CONCLUSION

N-acetyl cysteine, but not Silymarin/Silibinin, appears to be beneficial in prevention of ATT-DILI. However, the results were limited by the possible risk of bias in included studies, variable definitions of ATT-DILI and limited number and category of patients.