Analysis of 307 cases with drug-induced liver injury between 2010 and 2018 in Japan

Exploring Acute Liver Damage: Slimming Health Foods and CYP3A4 Induction

Background

Patients taking multiple drugs and various health foods often develop acute hepatitis. We hypothesized that the interaction between health foods and drug metabolism was the cause of severe liver injury in these patients. Therefore, we studied changes in the activity of the drug-metabolizing enzyme, cytochrome P450 (CYP), using slimming health food extracts and elucidated the molecular mechanism of liver injury onset through hepatotoxicity evaluation.

Methods

For cytotoxicity testing, health food extract samples were added to HepG2 cells derived from hepatic parenchymal cells and culture medium, and cell viability was calculated 48 h after culture. To evaluate CYP3A4 induction, 3-1-10 cells constructed with a reporter linked to CYP3A4 gene were used, and reporter activity was measured 48 h after culture.

Results

In the chronological order of the slimming health food intake history of the patient, niacinamide and Gymnema sylvestre extracts strongly inhibited HepG2 cell viability. In contrast, dietary supplements A and Coleus forskohlii extract strongly induced CYP3A4 reporter activity.

To confirm CYP3A4 induction in humans, humanized CYP3A/pregnane X receptor (PXR) mice were treated with forskolin. CYP3A4 mRNA expression levels were elevated 3.9 times compared to that of the control group (P < 0.05).

Conclusion

Coleus forskohlii extract showed the strongest transcriptional activation of CYP3A4 gene. In a mouse model of human-type drug metabolism, forskolin induced CYP3A4 transcription. Thus, we concluded that CYP3A4 induction by Coleus forskohlii is one of the causes of crucial hepatocellular injury, which is a type of liver injury caused by the active metabolite of acetaminophen produced by CYP3A4.

RECAM-J 2023-Validation and development of the Japanese version of RECAM for the diagnosis of drug-induced liver injury

AIM

The diagnosis of drug-induced liver injury (DILI) is challenging. We modified the revised electronic version of the Roussel Uclaf Causality Assessment Method (RUCAM) for the diagnosis of DILI (RECAM), the scoring system developed in US and Spanish cohorts in 2022, and developed RECAM-J 2023 to align with the clinical practice in Japan. In the current study, we introduce RECAM-J 2023 and verify its performance in the context of Japanese patients with DILI.

METHODS

After translation of RECAM into Japanese, modifications were made to develop RECAM-J 2023 without any alteration to the scores. To examine the validity and performance of RECAM-J 2023, clinical information on DILI and non-DILI cases in Japan were retrospectively collected. The diagnosis of DILI was made by expert's decision. Then we scored each case using RECAM-J 2023, and calculated area under curve (AUC) values for identification for DILI.

RESULTS

We collected data from 538 DILI and 128 non-DILI cases. The sum of highly probable (HP) and probable (PR) cases categorized by RECAM-J 2023 were only 206 (38%) in DILI cases. As the primary cause of low scores was the deduction with missing hepatitis virus markers, which is unlikely to be an issue in prospective applications, we rescored without these deductions. At this time, the sum of HP and PR was raised to 421 (78%). The AUCs of RECAM-J 2023 without deductions were 0.70 and 0.88 for identifying at least HP, and at least PR, respectively.

CONCLUSION

RECAM-J 2023, when prospectively used without any missing hepatitis virus markers, provides acceptable performance for identifying at least PR DILI cases in Japanese daily clinical practice.

Chinese guideline for the diagnosis and treatment of drug-induced liver injury: an update

Drug-induced liver injury (DILI) is an important adverse drug reaction that can lead to acute liver failure or even death in severe cases. Currently, the diagnosis of DILI still follows the strategy of exclusion. Therefore, a detailed history taking and a thorough and careful exclusion of other potential causes of liver injury is the key to correct diagnosis. This guideline was developed based on evidence-based medicine provided by the latest research advances and aims to provide professional guidance to clinicians on how to identify suspected DILI timely and standardize the diagnosis and management in clinical practice. Based on the clinical settings in China, the guideline also specifically focused on DILI in chronic liver disease, drug-induced viral hepatitis reactivation, common causing agents of DILI (herbal and dietary supplements, anti-tuberculosis drugs, and antineoplastic drugs), and signal of DILI in clinical trials and its assessment.

Acetaminophen-induced liver injury at therapeutic doses in a young adult: a case report

Acetaminophen causes volume-dependent hepatotoxicity; however, hepatotoxicity may also occur with acetaminophen administered at normal doses. We encountered a case of allergic liver damage in a 17-year-old girl receiving acetaminophen at a regular dose. The patient was diagnosed using the Roussel Uclaf Causality Assessment Method (RUCAM) and the diagnostic scale of the Digestive Disease Week Japan 2004 workshop. She tested positive for acetaminophen on a drug-induced lymphocyte stimulation test, and liver biopsy results confirmed the diagnosis of acetaminophen-induced liver injury. Despite administering acetaminophen at normal doses, hepatotoxicity may occur, which warrants further exploration.

Unveiling the therapeutic promise of natural products in alleviating drug-induced liver injury: Present advancements and future prospects

Drug-induced liver injury (DILI) refers to adverse reactions to small chemical compounds, biological agents, and medical products. These reactions can manifest as acute or chronic damage to the liver. From 1997 to 2016, eight drugs, including troglitazone, nefazodone, and lumiracoxib, were removed from the market due to their liver-damaging effects, which can cause diseases. We aimed to review the recent research on natural products and their bioactive components as hepatoprotective agents in mitigating DILI. Recent articles were fetched via searching the PubMed, PMC, Google Scholar, and Web of Science electronic databases from 2010 to January 2023 using relevant keywords such as "natural products," "acetaminophen," "antibiotics," "paracetamol," "DILI," "hepatoprotective," "drug-induced liver injury," "liver failure," and "mitigation." The studies reveal that the antituberculosis drug (acetaminophen) is the most frequent cause of DILI, and natural products have been largely explored in alleviating acetaminophen-induced liver injury. They exert significant hepatoprotective effects by preventing mitochondrial dysfunction and inflammation, inhibiting oxidative/nitrative stress, and macromolecular damage. Due to the bioavailability and dietary nature, using natural products alone or as an adjuvant with existing drugs is promising. To advance DILI management, it is crucial to conduct well-designed randomized clinical trials to evaluate natural products' efficacy and develop new molecules clinically. However, natural products are a promising solution for remedying drug-induced hepatotoxicity and lowering the risk of DILI.

Epidemiology and Management of Drug-induced Liver Injury: Importance of the Updated RUCAM

Drug-induced liver injury (DILI) is a major cause of acute liver injury, liver failure, and liver transplantation worldwide. In recent years, immune checkpoint inhibitors have become widely used. This has led to an increase in DILI, for which pathophysiology and management methods differ significantly from the past. As the number of cases of acute liver injury and liver transplantation due to DILI is expected to increase, information about a DILI is becoming more valuable. DILI is classified into two types according to its etiology: intrinsic DILI, in which the drug or its metabolites cause liver damage that is dose-dependent and predictable; and idiosyncratic DILI, in which liver damage is also dose-independent but unpredictable. In addition, depending on the course of the disease, chronic DILI or drug-induced autoimmune hepatitis may be present. The number of DILI cases caused by antimicrobial agents is decreasing, whereas that caused by drugs for malignant tumors and health foods is increasing. The Roussel Uclaf Causality Assessment Method is widely used to assess causality in DILI. Liver injury is a type of immune-related adverse event. The pattern of hepatic injury in immune-related adverse events is mostly hepatocellular, but mixed type and bile stasis have also been reported. Sclerosing cholangitis caused by immune checkpoint inhibitors has also been reported as a unique type of injury. Treatment mainly comprises withdrawal of immune checkpoint inhibitors and steroid administration; however, mycophenolate mofetil may be considered if the disease is refractory to steroids.

Disproportionality analysis of acetaminophen-induced hepatic disorders with and without immune checkpoint inhibitors

BACKGROUND

Although acetaminophen is recommended for the treatment of mild-to-moderate cancer pain, acetaminophen-induced hepatic disorders pose an important clinical challenge. Concomitant prescription of immune checkpoint inhibitors (ICIs) may further increase the risk of hepatic disorders in patients taking acetaminophen; however, there are few clinical studies that confirm this.

AIM

To evaluate the risk of hepatic disorders in patients taking concomitant acetaminophen and ICIs using a disproportionality analysis from the Japanese Adverse Drug Event Report database.

METHOD

Acetaminophen users aged ≥ 20 years were included; factors that can affect the risk of acetaminophen-induced hepatic disorders were collated. Similar data on the widely used analgesic, loxoprofen, were used for comparison.

RESULTS

Among 233,594 patients surveyed, 10,403 were prescribed acetaminophen, and among them, 1,245 patients developed hepatic disorders. The disproportionality of hepatic disorders was observed in acetaminophen users regardless of concomitant ICI use (without ICI: reporting odds ratio [ROR], 1.18; 95% confidence intervals [CI], 1.10-1.26; with ICI: ROR 1.87, 95%CI 1.59-2.20); it was even higher in concomitant acetaminophen and ICI users (ROR 1.94, 95%CI 1.65-2.29). However, increased disproportionality of hepatic disorders was not observed in patients taking concomitant loxoprofen and ICI. Multivariable logistic regression showed that the risk of hepatic disorders in acetaminophen users was associated with concomitant use of ICI (ROR, 1.91; 95% CI, 1.49-2.45); (P < 0.01).

CONCLUSION

Our findings suggest that the risk of hepatic disorders is greater with concomitant acetaminophen and ICI treatment than with acetaminophen alone.

Significant association between HLA-B*35:01 and onset of drug-induced liver injury caused by Kampo medicines in Japanese patients

AIM

Drug-induced liver injury (DILI) is a severe and life-threatening immune-mediated adverse effect, occurring rarely among treated patients. We examined genomic biomarkers in the Japanese population that predict the onset of DILI after using a certain class of drugs, such as Kampo products (Japanese traditional medicines).

METHODS

A total of 287 patients diagnosed as DILI by hepatology specialists were recruited after written informed consent was obtained. A genome-wide association analysis and human leukocyte antigen (HLA) typing in four digits were performed.

RESULTS

We found a significant association (p = 9.41 × 10^-10 ) of rs146644517 (G > A) with Kampo product-related DILI. As this polymorphism is located in the HLA region, we evaluated the association of HLA types and found that 12 (63.2%) of 19 Kampo-DILI patients contained HLA-B*35:01, whereas only 15.2% were positive for this HLA among healthy volunteers. The odds ratio was 9.56 (95% confidence interval 3.75-24.46; p = 2.98 × 10^-6 , corrected p = 4.17 × 10^-5 ), and it increased to 13.55 compared with the DILI patients not exposed to Kampo products. The individual crude drug components in the Kampo products, including Scutellaria root (ougon in Japanese), rhubarb (daiou), Gardenia fruit (sanshishi), and Glycyrrhiza (kanzou), were significantly associated with HLA-B*35:01.

CONCLUSIONS

HLA-B*35:01 is a genetic risk factor and a potential predictive biomarker for Kampo-induced DILI in the Japanese population.

L-carbocisteine can cause cholestasis with vanishing bile duct syndrome in children: A case report

RATIONALE

Vanishing bile duct syndrome (VBDS) is the acquired progressive destruction and disappearance of intrahepatic interlobular bile ducts in the absence of underlying liver or biliary tract disease, causing chronic cholestasis. Infections, drugs, toxins, malignant diseases, and certain immunological processes are associated with the development of this syndrome. There have been no reports of children developing VBDS as a consequence of the administration of L-carbocisteine.

PATIENT CONCERNS

A 9-year-old Japanese girl presented with fever, jaundice, and skin rash. Laboratory investigations revealed elevated levels of serum transaminases, γ-glutamyltransferase, and bilirubin. Histopathological features were consistent with a diagnosis of VBDS. Drug-induced lymphocyte stimulation tests (DLST) were positive for L-carbocisteine.

DIAGNOSIS

VBDS caused by L-carbocisteine.

INTERVENTIONS

Ursodeoxycholic acid and discontinuation of L-carbocisteine.

OUTCOMES

The patient responded to treatment based upon discontinuation of L-carbocisteine and administration of ursodeoxycholic acid. Her transaminase and bilirubin levels were normalized gradually.

LESSONS

Physicians should be aware of the fact that L-carbocisteine can cause cholestasis with VBDS in children.

A review of herb-induced liver injury in mainland china

Traditional medicines have greatly contributed to people’s health worldwide. However, in recent years, the frequent occurrence of herb-induced liver injury (HILI) has raised public concerns regarding the safety of herbs. HILI not only severely impacts public health, thus increasing its medical burden, but also consumes medical resources. However, the pharmacoepidemiology and risk factors of HILI are still unclear due to the complexity of herbs (medication theory, drug composition, dual properties of drugs and food, etc.). China is the country with the most extensive use of herbs and cases of HILI worldwide. The safety profile of herbs (especially with respect to HILI) has also affected the use of herbs internationally. Therefore, this review focuses on the epidemic situation of HILI in mainland China to compile its characteristics, while focusing on the three main aspects of patients, drugs, and unreasonable prescriptions to explore the potential risk factors. Our objective was to provide a reference for HILI pharmacovigilance and risk prevention and control and contribute to Chinese knowledge of the realisation of the “Medication without Harm” global safe medication strategic goal of the World Health Organization.

Frequency of null genotypes of glutathione S-transferase M1 and T1 in Japanese patients with drug-induced liver injury

AIM

Previous reports suggest that the null genotype (*0/*0) of glutathione S-transferase (GST) M1 and/or GSTT1 could be risk factors for drug-induced liver injury (DILI). However, multi-institutional pharmacogenetic research with various suspected drugs has rarely been performed in Japan. Therefore, the aim of this study was to investigate the role of GSTM1 and GSTT1 null genotype in the occurrence of DILI in Japanese patients.

METHODS

Blood samples of 270 DILI patients from 23 hospitals throughout Japan collected between 2010 and 2018 were subjected to genotyping of null genotypes of GSTM1 and GSTT1 using the SmartAmp-2 method. We also collected information on DILI types, time to onset of DILI, pharmacological classification of suspected drugs and Digestive Disease Week-Japan score, as well as genotypes of GSTM1 and GSTT1 in each patient with DILI.

RESULTS

The distribution of a combination of null genotypes of GSTM1 and GSTT1 in Japanese patients with DILI was significantly different from that reported in the general Japanese population. Notably, the incidence of the GSTM1 null genotype in patients with DILI was significantly higher than that of the control population. A significant relationship between the frequency of GSTM1 and GSTT1 null genotypes and pharmacological classification of suspected drugs, clinical laboratory data for liver function, time to onset of DILI, and Digestive Disease Week-Japan scores was not observed.

CONCLUSIONS

The GSTM1 null genotype was associated with an increased incidence of DILI in Japanese patients.

Differences in clinical characteristics among 726 patients with Chinese herbal medicine- or Western medicine-induced liver injury

The differences between Chinese herbal medicine (CHM)- and Western medicine (WM)-induced liver injury have rarely been reported. Our aim was to investigate the clinical features of patients with drug-induced liver injury (DILI) caused by CHM or WM. The medical records of 726 DILI patients were retrospectively collected at Peking University First Hospital from January 1995 through August 2019. The number of inpatients with DILI in our hospital showed an increasing trend over time. The incidence of DILI caused by CHM exhibited a linear trend toward an increase with time (P = .0012). Of the 726 DILI patients, females accounted for 65.8%. There were 353 cases (48.6%) caused by CHM and 225 cases (40.0%) caused by WM. The 3 most common causative CHMs were Polygonum multiflorum (38 cases), Fructus Psoraleae (35 cases), and Epimedium (26 cases). The proportions of female patients, alanine aminotransferase (ALT) levels, aspartate aminotransferase (AST) levels, total bilirubin (TBIL) levels and antinuclear antibody (ANA) positivity rates among cases caused by CHM were higher than those of cases caused by WM (P < .05). There were more patients with severe cases caused by CHM than with severe cases caused by WM (P < .05). The clinical characteristics of DILI caused by CHM differ from those caused by WM. The incidence of DILI caused by CHM is increasing yearly. The medication time of DILI caused by CHM is longer than that of DILI caused by WM, and the severity is greater. Therefore, it is necessary to scientifically and rationally use traditional CHM and monitor liver function. For DILI caused by CHM, the CHM prescription should be recorded in detail to provide detailed clinical data for scientific research on the liver toxicity of CHM.

Incidence and risk factors of drug-induced liver injury

The epidemiology and aetiology of drug-induced liver injury (DILI) vary across different countries and populations. Overall, DILI is rare in the general population but has become more prevalent in hospitalized patients, especially among patients with unexplained liver conditions. In addition, drugs implicated in DILI differ between Western and Eastern countries. Antibiotics are the leading drugs implicated in DILI in the West, whereas traditional Chinese medicine is the primary cause implicated in DILI in the East. The incidence of herbal and dietary supplements-induced hepatotoxicity is increasing globally. Several genetic and nongenetic risk factors associated with DILI have been described in the literature; however, there are no confirmed risk factors for all-cause DILI. Some factors may contribute to the risk of DILI in a drug-specific manner.

Herbal and Dietary Supplements-Induced Liver Injury in Latin America: Experience From the LATINDILI Network

BACKGROUND

Herbal and dietary supplements (HDS) consumption, a growing cause of hepatotoxicity, is a common practice among Latin-American populations.

OBJECTIVES

To evaluate clinical, laboratory features and outcome in HDS-hepatotoxicity included in the Latin America-Drug Induced Liver Injury (LATINDILI) Network.

METHODS

A total of 29 adjudicated cases of HDS hepatotoxicity reported to the LATINDILI Network from October 2011 through December 2019 were compared with 322 DILI cases due to conventional drugs and 16 due to anabolic steroids as well as with other series of HDS-hepatotoxicity.

RESULTS

From 367 DILI cases, 8% were attributed to HDS. An increasing trend in HDS-hepatotoxicity was noted over time (p = .04). Camellia sinensis, Herbalife® products, and Garcinia cambogia, mostly used for weight loss, were the most frequently adjudicated causative agents. Mean age was 45 years (66% female). Median time to onset was 31 days. Patients presented typically with hepatocellular injury (83%) and jaundice (66%). Five cases (17%) developed acute liver failure. Compared to conventional medications and anabolic steroids, HDS hepatotoxicity cases had the highest levels of aspartate and alanine transaminase (p = .008 and p = .021, respectively), had more re-exposure events to the culprit HDS (14% vs 3% vs 0%; p = .026), and had more severe and fatal/liver transplantation outcomes (21% vs 12% vs 13%; p = .005). Compared to other DILI cohorts, less HDS hepatotoxicity cases in Latin America were hospitalized (41%).

CONCLUSIONS

HDS-hepatotoxicity in Latin-America affects mainly young women, manifests mostly with hepatocellular injury and is associated with higher frequency of accidental re-exposure. HDS hepatotoxicity is more serious with a higher chance of death/liver transplantation than DILI related to conventional drugs.

Anaphylactic Reactions Caused by Nafamostat Mesylate during Hemodialysis before Surgery for Carpal Tunnel Syndrome

Nafamostat mesylate (NM) has been used to treat pancreatitis and disseminated intravascular coagulation during hemodialysis (HD). However, there have been some reports of adverse effects related to anaphylactic reactions. We present a case in which anaphylactic reactions caused by NM during preoperative HD caused repeated postponement of surgery for carpal tunnel syndrome. Symptoms including fever, shivering, chills, low blood pressure, tachycardia, nausea, and vomiting appeared during preoperative HD, and surgery was postponed thrice. Initially, the patient was misdiagnosed with sepsis because of elevated C-reactive protein and procalcitonin levels. However, since the symptoms appeared only when NM was administered and disappeared quickly after the administration of NM was terminated, the condition was diagnosed as anaphylactic reactions caused by NM. Therefore, it is essential to consider anaphylactic reactions caused by NM as differential diagnoses, when symptoms, such as fever, are observed during perioperative HD.

Real-World Data of Tigecycline-Associated Drug-Induced Liver Injury Among Patients in China: A 3-year Retrospective Study as Assessed by the Updated RUCAM

Background: Tigecycline, a glycylcycline antibiotic, is increasingly used clinically for the treatment of severe infections caused by multidrug-resistant bacteria, but it is also associated with hepatotoxicity. However, the incidence and risk factors of tigecycline-associated drug-induced liver injury (DILI) are unclear. We conducted this study to investigate the incidence, characteristics and risk factors of tigecycline-associated DILI in the real-world clinic setting. Patients and Methods: A retrospective analysis was conducted in inpatients who received tigecycline treatment from January 2018 to January 2020. Based on the biochemical criteria of DILI and the causality assessment by Roussel Uclaf Causality Assessment Method (RUCAM) using cases with a probable or highly probable causality grading, two clinical pharmacists and one clinician worked together to screen patients for tigecycline-associated DILI. Then patients with DILI were randomly matched by gender in a ratio of 1:2 to the remaining patients in the tigecycline cohort without biochemical abnormalities to identify risk factors. Results: A total of 973 patients from 1,250 initial participants were included. The incidence of tigecycline-associated DILI was 5.7% (55/973). Among 55 DILI patients, 10 cases presented with the hepatocellular pattern, 4 cases belonged to the mixed pattern, and 41 presented with the cholestatic pattern. Most cases reached the severity of grade 1 and 2. The rate of recovery in hepatocellular pattern, mixed pattern, and cholestatic pattern was 70.0, 50.0, and 41.5%, respectively. The proportion of the DILI cases treated with high dose (100 mg) and prolonged duration (>14 days) was significantly higher than standard dose and routine duration (100.0% vs. 18.1%, p < 0.05). Logistic regression analysis showed that high maintenance dose (OR = 1.028, p = 0.002), prolonged duration (OR = 1.208, p = 0.000), and number of hepatotoxic drugs (OR = 2.232, p = 0.000) were independent factors of tigecycline-associated DILI. Conclusion: Tigecycline was associated with liver injury, with a slightly higher incidence (5.7%) than the frequency of "frequent" (5%) defined by the Medical Dictionary for Regulatory Activities. Patients with a high maintenance dose and prolonged tigecycline regimen, as well as concomitant use of multiple hepatotoxic drugs should be paid more attention.

Signal Detection of Potential Hepatotoxic Drugs: Case-Control Study Using Both a Spontaneous Reporting System and Electronic Medical Records

Drug-induced liver injury (DILI) is a common adverse drug event. Spontaneous reporting systems such as the Japanese Adverse Event Report Database (JADER) have been used to evaluate the association between drugs and adverse drug events. However, the association of drugs with adverse drug events may be overestimated due to reporting biases. Therefore, it is important to objectively evaluate the association using liver function test values. The aim of the present study was to predict potential hepatotoxic drugs using real-world data including electronic medical records and the JADER database. A total of 70009 (2779 with DILI and 67230 without DILI) and 438515 (10235 with DILI and 428280 without DILI) Japanese adult patients were extracted from electronic medical records and the JADER database, respectively. Drugs with ≥100 DILI patients in both of the two databases were regarded as suspected drugs for DILI. We used multivariate logistic regression to evaluate the association between the suspected drugs and increased risk of DILI. Among the suspected drugs, broad-spectrum antibiotics such as meropenem, tazobactam/piperacillin and ceftriaxone were significantly associated with an increased risk of DILI, and meropenem had a greater risk of DILI in both of the two databases. Additionally, there were significant associations of mosapride and L-carbocisteine with increased risk of DILI. In addition to well-known associations between antibiotic drugs and DILI, mosapride and L-carbocisteine were found to be new potential signals of drugs causing hepatotoxicity. This study indicates potential hepatotoxic drugs that require further causality assessment.

The Diagnosis of Drug-induced Liver Injury: Current Diagnostic Ability and Future Challenges of the Digestive Disease Week-Japan 2004 Scale 15 Years after Its Proposal

Objective This study examined whether or not the Digestive Disease Week-Japan (DDW-J) 2004 scale proposed over 15 years ago can be applied to current cases of drug-induced liver injury (DILI). Methods The new patients group included 125 patients from 2012 to 2019 and was divided into 2 subgroups: 96 patients in the new DILI group and 29 patients in the new non-DILI group. Similarly, the old patients group included 105 patients from 1997 to 2002 and was divided into 2 subgroups: 59 patients in the old DILI group and 46 patients in the old non-DILI group. Patients were assessed by the DDW-J 2004 scale; those with a score ≥3 were defined as having DILI. Results The total score of the new DILI group was significantly lower than that of the old DILI group [6 (1-11) vs. 6 (3-9), p=0.004]. The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) were 94.8%, 65.6%, 90.1%, and 79.2%, respectively, in the new patients group and 100%, 91.4%, 93.7%, and 100%, respectively, in the old patients group. The specificity and NPV of the new patients group were significantly lower than those of the old patients group. Conclusion The DDW-J 2004 scale maintains a stable diagnostic ability for DILI, regardless of differences in eras and verification methods. However, differential diagnoses can affect the scoring, and new types of DILI, such as immune-related adverse events, must be addressed. Therefore, upgrading the scale should be considered.

Severe Liver Injury Associated with Glecaprevir Plus Pibrentasvir Therapy in a Patient with Treatment-naïve Hepatitis C Virus Infection

A 49-year-old man underwent treatment with glecaprevir plus pibrentasvir (G/P) for chronic hepatitis C infection. Six weeks later, he was admitted to our hospital because of jaundice and fatigue with no accompanying skin rash. A laboratory examination and evaluation of the patient's history resulted in a diagnosis of acute liver injury. Discontinuation of G/P and a rigorous medical protocol, including plasma exchange and hemodiafiltration, successfully mitigated the liver damage. The patient was also found to be allergic to two drugs other than the G/P therapy. In such cases with a history of drug allergy, careful observation may be required to detect serious adverse events.

Comprehensive analysis and insights gained from long-term experience of the Spanish DILI Registry

BACKGROUND & AIMS

Prospective drug-induced liver injury (DILI) registries are important sources of information on idiosyncratic DILI. We aimed to present a comprehensive analysis of 843 patients with DILI enrolled into the Spanish DILI Registry over a 20-year time period.

METHODS

Cases were identified, diagnosed and followed prospectively. Clinical features, drug information and outcome data were collected.

RESULTS

A total of 843 patients, with a mean age of 54 years (48% females), were enrolled up to 2018. Hepatocellular injury was associated with younger age (adjusted odds ratio [aOR] per year 0.983; 95% CI 0.974-0.991) and lower platelet count (aOR per unit 0.996; 95% CI 0.994-0.998). Anti-infectives were the most common causative drug class (40%). Liver-related mortality was more frequent in patients with hepatocellular damage aged ≥65 years (p = 0.0083) and in patients with underlying liver disease (p = 0.0221). Independent predictors of liver-related death/transplantation included nR-based hepatocellular injury, female sex, higher onset aspartate aminotransferase (AST) and bilirubin values. nR-based hepatocellular injury was not associated with 6-month overall mortality, for which comorbidity burden played a more important role. The prognostic capacity of Hy's law varied between causative agents. Empirical therapy (corticosteroids, ursodeoxycholic acid and MARS) was prescribed to 20% of patients. Drug-induced autoimmune hepatitis patients (26 cases) were mainly females (62%) with hepatocellular damage (92%), who more frequently received immunosuppressive therapy (58%).

CONCLUSIONS

AST elevation at onset is a strong predictor of poor outcome and should be routinely assessed in DILI evaluation. Mortality is higher in older patients with hepatocellular damage and patients with underlying hepatic conditions. The Spanish DILI Registry is a valuable tool in the identification of causative drugs, clinical signatures and prognostic risk factors in DILI and can aid physicians in DILI characterisation and management.

LAY SUMMARY

Clinical information on drug-induced liver injury (DILI) collected from enrolled patients in the Spanish DILI Registry can guide physicians in the decision-making process. We have found that older patients with hepatocellular type liver injury and patients with additional liver conditions are at a higher risk of mortality. The type of liver injury, patient sex and analytical values of aspartate aminotransferase and total bilirubin can also help predict clinical outcomes.

Hepatic Macrophage activation and the LPS pathway in patients with different degrees of severity and histopathological patterns of drug induced liver injury

BACKGROUND

Inflammatory activation of hepatic macrophages plays a primary role in drug-induced liver injury (DILI). However, the exact mechanism underlying DILI remains unclear.

METHODS

A total of 328 DILI patients and 80 healthy individuals were prospectively enrolled in this study. The DILI patients were categorized into subgroups based on either disease severity or histopathological patterns. Plasma soluble CD163 (sCD163) and hepatic CD163 were examined to determine hepatic macrophage activation, and CD8, CD20, and MUM-1 were assessed to determine cellular immunity using immunohistochemistry. The lipopolysaccharide (LPS) pathway proteins [e.g. LPS, soluble CD14 (sCD14), and LPS-binding protein (LBP)] were measured using enzyme-linked immunosorbent assay.

RESULTS

Plasma sCD163 levels were nine-fold higher in DILI patients than in healthy controls at the baseline, but significantly decreased at the 4-week follow-up visit after treatment. The numbers of hepatic macrophages, B cells, and plasma cells were significantly higher in the liver tissues from DILI patients than those from healthy controls. Furthermore, the baseline levels of LPS pathway proteins in the DILI patients were significantly higher than those in the controls. Notably, these proteins significantly decreased at the 4-week follow-up visit but remained significantly higher than the levels for the controls.

CONCLUSIONS

Hepatic inflammation in DILI involves the activation of hepatic macrophages and cellular immunity, in which the LPS pathway likely plays a role, at least in part. As such, this study has improved our understanding of the pathological mechanisms for DILI and may facilitate the development of better treatments for patients with DILI.

Prediction of oral hepatotoxic dose of natural products derived from traditional Chinese medicines based on SVM classifier and PBPK modeling

The risk of drug-induced liver injury (DILI) poses a major challenge for development of natural products derived from traditional Chinese medicines (NP-TCMs). It is urgent to find a new method for the safety assessment of the NP-TCMs. Recent study has reported an in vitro/in silico method to estimate the acceptable daily intake of hepatotoxic compounds using support vector machine (SVM) classifier and physiologically based pharmacokinetic (PBPK) modeling. However, this method is not suitable for estimating the dosing schedule of compounds which are administered in multiple daily doses. Thus, in this study, the method mentioned above was in particular optimized, and used to estimate the hepatotoxic plasma concentrations of 17 NP-TCMs. Additionally, the oral dosing schedules of the triptolide, emodin, matrine and oxymatrine were also predicted by the SVM classifier and PBPK modeling. The optimization included that: (1) in vitro cytotoxicity data of 28 training set compounds was optimized using benchmark concentrations (BMC) modeling; (2) AUC of the training set compound was used as the in vivo metric instead of C_max to better reflect the total daily exposure of compounds which are administered in multiple daily doses; (3) using the mean AUC in plasma as in vivo metric and BMC value as in vitro metric could achieve the better toxicity separation index (0.962 vs. 0.938); (4) The TSI for C_max and BMC values was 0.985 calculated in this study, and the results indicated that BMC modeling improved the separation performance. This optimized in vitro-in vivo extrapolation (IVIVE) workflow could extrapolate in vitro BMC to blood concentrations and the oral dosing schedule which are corresponding to certain risk of hepatotoxicity. The estimated safe dosing schedule of oxymatrine by this optimized method was close to the clinical recommended dosing regimen. The results indicate that the optimized method could be used to predict the dosing schedule of compounds administered in multiple daily doses, and our optimized workflow could be helpful for the safety assessment as well as the research and development on NP-TCMs.

Drug-induced liver injury: Asia Pacific Association of Study of Liver consensus guidelines

Idiosyncratic drug-induced liver injury mimics acute and chronic liver disease. It is under recognized and underrecognised because of the lack of pathognomonic diagnostic serological markers. Its consequences may vary from being asymptomatic to self-limiting illness to severe liver injury leading to acute liver failure. Its incidence is likely to be more common in Asia than other parts of the world, mainly because of hepatotoxicity resulting from the treatment of tuberculosis disease and the ubiquitous use of traditional and complimentary medicines in Asian countries. This APASL consensus guidelines on DILI is a concise account of the various aspects including current evidence-based information on DILI with special emphasis on DILI due to antituberculosis agents and traditional and complementary medicine use in Asia.

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

Background: A large number of idiosyncratic drug induced liver injury (iDILI) and herb induced liver injury(HILI) cases of variable quality has been published but some are a matter of concern if the cases were not evaluated for causality using a robust causality assessment method (CAM) such as RUCAM (Roussel Uclaf Causality Assessment Method) as diagnostiinjuryc algorithm. The purpose of this analysis was to evaluate the worldwide use of RUCAM in iDILI and HILI cases. Methods: The PubMed database (1993-30 June 2020) was searched for articles by using the following key terms: Roussel Uclaf Causality Assessment Method; RUCAM; Idiosyncratic drug induced liver injury; iDILI; Herb induced liver injury; HILI. Results: Considering reports published worldwide since 1993, our analysis showed the use of RUCAM for causality assessment in 95,885 cases of liver injury including 81,856 cases of idiosyncratic DILI and 14,029 cases of HILI. Among the top countries providing RUCAM based DILI cases were, in decreasing order, China, the US, Germany, Korea, and Italy, with China, Korea, Germany, India, and the US as the top countries for HILI. Conclusion: Since 1993 RUCAM is certainly the most widely used method to assess causality in IDILI and HILI. This should encourage practitioner, experts, and regulatory agencies to use it in order to reinforce their diagnosis and to take sound decisions.

Plasma Lipid Profiling of Three Types of Drug-Induced Liver Injury in Japanese Patients: A Preliminary Study

Drug-induced liver injury (DILI) is a major adverse event caused by drug treatment, which can be categorized into three types: hepatocellular, mixed, and cholestatic. Although nearly every class of drugs can cause DILI, an overall understanding of lipid profiles in DILI patients is lacking. We used lipidomics to analyze the plasma lipid profiles of patients to understand their hepatic pathophysiology and identify DILI biomarkers. We identified 463 lipids and compared their levels between the acute and recovery phases of the three types of DILI patients. Mixed and cholestatic types demonstrated specific plasma lipid alterations between the phases, but the hepatocellular type did not. Moreover, as specific indicators of mixed-type DILI, levels of several ceramides increased in the acute phase, while those of arachidonic acid-containing ether-linked phosphoglycerolipids decreased. In contrast, as specific indicators of cholestatic-type DILI, levels of palmitic acid-containing saturated or monounsaturated phosphatidylcholines increased in the acute phase, while those of arachidonic acid- or docosahexaenoic acid-containing ether-linked phosphoglycerolipids and phosphatidylinositols decreased. We also identified lipids with a relatively high capacity to discriminate the acute phase from the recovery phase and healthy subjects. These findings may help with understanding the pathophysiology of different DILI types and identify candidate biomarkers.

A sensitive upconverting nanoprobe based on signal amplification technology for real-time in situ monitoring of drug-induced liver injury

Drug-induced liver injury (DILI) is increasingly recognized as one of the most challenging global health problems. Conventional in vitro detection methods not only lack specificity and sensitivity but also cannot achieve real-time, straightforward visualization of hepatotoxicity in vivo. Liver-specific miR122 has been observed to be a superior and sensitive biomarker for DILI diagnosis. Herein, a sensitive upconverting nanoprobe synthesized with upconversion nanoparticles (UCNPs) and gold nanorods (GNR) was designed to diagnose hepatotoxicity in vivo. After injection, the nanoprobes accumulated in the liver and were activated by miR122, and the signal amplification technology fully yielded luminescent amplification; hence, the detection sensitivity was improved. Because of the high tissue penetration capability of near-infrared light, this nanoprobe can achieve real-time in situ detection, thereby providing a novel technology for precise biological and medical analysis.

The Association Between Concurrence of Infection and the Onset of Severe Eruption or Liver Injury in Patients Using Antipyretic Analgesics: A Matched, Nested Case-Control Study

Stevens-Johnson syndrome (SJS) and toxic epidermal necrosis (TEN) or drug-induced liver injury (DILI) are severe drug-induced reactions, known as idiosyncratic drug reactions. It is believed that immune response can lead to these severe adverse drug reactions. Our previous analysis of the Japanese Spontaneous Drug Reaction database suggested that the onset of SJS/TEN and DILI was strongly associated with infection. Hence, we conducted a matched, nested case-control study to elucidate the association between concurrent infection and the onset of SJS/TEN or liver injury in patients prescribed antipyretic analgesics. We extracted 4 112 055 patients who were prescribed antipyretic analgesics between January 2014 and December 2015. Amongst them, 553 (0.01%) were diagnosed with SJS/TEN and 12 606 (0.3%) with liver injury. In a matched, nested case-control study, 131 and 2847 cases matched for SJS/TEN or liver injury, respectively. For each case, 3 controls were randomly matched with the case for age at index date and sex. In the conditional logistic regression analysis, there was a significant association between the combination of infection and antipyretic analgesics and the onset of SJS/TEN or liver injury (SJS/TEN: adjusted OR, 5.59; 95%CI, 2.01-15.51; liver injury: adjusted OR, 2.79; 95%CI, 2.24-3.46). Although it was not possible to distinguish whether the associations were caused by the infection or were a direct consequence of the antibiotic agents, our findings may help to increase awareness of the possibility of the increased onset of idiosyncratic drug reactions (SJS/TEN and liver injury) in antipyretic analgesic users because of infections.

Non-alcoholic fatty liver disease is a potential risk factor for liver injury caused by immune checkpoint inhibitor

BACKGROUND AND AIM

Because of their survival benefits, immune checkpoint inhibitors (ICIs) are widely administered to patients with various advanced-stage malignancies. During ICI treatment, drug-induced liver injury (DILI) occasionally occurs. In particular, hepatic immune-related adverse events (irAEs) are rare but serious and fatal. In patients with hepatic irAEs, immediate steroid treatment is generally recommended; however, the risk factors for ICI-associated DILI remain unknown. In the present study, we identified a risk factor for ICI-associated DILI.

METHODS

We retrospectively analyzed 135 patients treated with anti-programmed cell death-1 (PD-1) antibodies, such as nivolumab and pembrolizumab, at Asahikawa Medical University Hospital. We investigated grade ≥ 2 hepatotoxic AEs during anti-PD-1 therapy, and PD-1 inhibitor-associated DILI was then diagnosed according to the Digestive Disease Week Japan (DDW-J) 2004 scale. The risk factors for PD-1 inhibitor-associated DILI were identified by Cox hazard analysis.

RESULTS

Thirty-six patients developed grade ≥ 2 hepatic AEs during anti-PD-1 therapy. Among them, eight patients were diagnosed with PD-1 inhibitor-associated DILI based on the DDW-J 2004 scale. Cox hazard analysis revealed that non-alcoholic fatty liver disease (NAFLD) was a risk factor for PD-1 inhibitor-associated DILI. In addition, we revealed that the outcomes of patients with the DDW-J 2004 score = 3 were improved without steroid treatment.

CONCLUSIONS

NAFLD is a potential risk factor for PD-1 inhibitor-associated DILI based on the DDW-J 2004 scale. The DDW-J 2004 scale might be useful for determining whether steroid treatment is required in patients with PD-1 inhibitor-associated DILI.

Prolonged interval of total bilirubin decline is an early independent predictive factor of chronic persistent drug-induced liver injury

AIM

Chronic drug-induced liver injury (DILI) with persistent abnormal liver function tests (LFTs) >6 months after cessation of the insulting drugs could progress to cirrhosis. The aim of the present study was to identify the risk factors of chronic DILI for early recognition and better management.

METHODS

History of drug intake and results of LFTs were retrospectively retrieved for patients with a discharge diagnosis of DILI for at least 1-year follow up. The risk factors independently associated with chronic DILI were analyzed by multiple logistic regression analyses.

RESULTS

A total of 33 of the 140 DILI patients had persistent abnormal LFTs >6 months, which were considered as chronic DILI. It was found that the time intervals of alanine aminotransferase and total bilirubin decline from the peak to their half peak (T_0.5ALT , T_0.5TBIL ) were significantly longer in the chronic DILI group than that in the recovered group (P = 0.001 and P < 0.001). The risk factors associated with chronic DILI independently were T_0.5TBIL (OR 1.315, 95% CI 1.038-1.668), longer period of insulting drug(s) intake (OR 1.018, 95% CI 1.003-1.033), mixed/cholestatic pattern (OR 97.159, 95% CI 1.866-5005.994). More importantly, receiver operating characteristic curve analysis showed that the prognostic value of T_0.5TBIL for chronic DILI had a sensitivity of 60.0% at a specificity of 90.7% with the threshold of 16 days.

CONCLUSIONS

The time intervals of total bilirubin decline from its peak to half of its peak (T_0.5TBIL ) was an early independent predictive factor of chronic DILI, suggesting that T_0.5TBIL might serve as an indicator for chronicity.

Factors associated with longitudinal changes in serum concentrations of Mac-2 binding protein: A prospective 3-year observational study

BACKGROUND AND AIMS

Mac-2 binding protein (M2BP) plays an important role in cell adhesion. In a recent cross-sectional study we reported that serum M2BP concentrations may reflect silent atherosclerosis. The aim of the present prospective follow-up study was to investigate possible relationships between changes in concentrations of M2BP and other factors over a >3-year period.

METHODS AND RESULTS

The present study enrolled subjects who visited Enshu hospital from 2014 to 2015 for a periodic physical check-up and then attended for another physical check-up after >3 years (n = 174). Factors affecting changes in M2BP concentrations were investigated at both baseline and follow-up. Subjects with liver dysfunction, a history of hepatic disease, malignant neoplasm, or cardiovascular events at baseline were excluded. Univariate and multivariate regression analyses showed that changes in serum M2BP concentrations during the follow-up period were significantly associated with changes in low-density lipoprotein cholesterol (LDL-C), triglyceride, and oxidative stress marker derivatives of reactive oxygen metabolites (d-ROM) concentrations. Moreover, the increase in LDL-C was significantly greater in subjects in whom M2BP concentrations increased during the follow-up period. Logistic regression analysis with an endpoint of increased M2BP revealed that increased LDL-C was an independent determinant of an increase in M2BP during the follow-up period.

CONCLUSION

During the observation period of >3 years, serum M2BP concentrations were increased in subjects who also exhibited increases in levels of metabolic parameters, especially LDL-C, and the oxidative stress marker d-ROM. These results support that serum M2BP reflects one of the contributors to the progression of silent atherosclerosis.

Unfavorable prognosis of patients with acute liver injury due to drug-induced liver injury and acute exacerbation of hepatitis B virus infection

AIM

Acute liver injury (ALI) has a favorable prognosis, whereas acute liver failure (ALF) leads to organ failure and thus has an unfavorable prognosis. The effect of each etiology on the clinical course of ALI remains unclear. This study aimed to determine how each etiology and glucocorticoid on the unfavorable etiology affects the clinical course of ALI.

METHODS

This prospective observational study enrolled 522 patients with ALI/ALF from 2004 and 2017. To evaluate the influence of etiology on prognosis, decision tree analysis was carried out using age, disease type, etiology, and the presence of hepatic encephalopathy.

RESULTS

Of 522 patients, 398 patients satisfied the ALI criteria at registration in this study. The ALI etiologies were as follows: viral hepatitis through oral infection (n = 54), acute hepatitis B virus (HBV) infection (n = 24), acute exacerbation of HBV infection (n = 30), de novo hepatitis due to HBV (n = 5), autoimmune hepatitis (n = 59), drug-induced liver injury (DILI; n = 85), other viruses (n = 12), and undetermined (n = 129). ALI in 46 patients progressed to ALF after registration. Of 11 patients (age >52 years) with ALF due to acute exacerbation of HBV infection or DILI, seven patients (63.6%) died. Whether glucocorticoid affected the clinical course of ALI due to acute exacerbation of HBV infection or DILI was evaluated using propensity score matching (age, sex, alanine aminotransferase, total bilirubin, and prothrombin time-international normalized ratio). Glucocorticoid did not improve the prognosis of ALI patients due to the two etiologies.

CONCLUSIONS

Progression of ALI due to DILI or acute exacerbation of HBV infection to ALF showed a poor prognosis.

Epidemiological differences of common liver conditions between Asia and the West

Liver diseases form a heterogenous group of acute and chronic disorders of varying etiologies. Not only do they result in significant morbidity and mortality, but they also lead to a marked reduction in quality of life, together with a high socioeconomic burden globally. A better understanding of their global distribution is necessary to curb the massive health-care and socioeconomic burden that they entail. Notable differences and similarities have been described between common liver disease conditions occurring in Asia and the West (Europe and North America), giving rise to the need for an updated collective appraisal of this subject. In this review, the epidemiological differences of common liver conditions, specifically acute liver failure, drug-induced liver injury, acute-on-chronic liver failure, hepatocellular carcinoma, and non-alcoholic fatty liver disease, between Asia and the West are discussed.

Drug-induced liver injury

Drug-induced liver injury (DILI) is an adverse reaction to drugs or other xenobiotics that occurs either as a predictable event when an individual is exposed to toxic doses of some compounds or as an unpredictable event with many drugs in common use. Drugs can be harmful to the liver in susceptible individuals owing to genetic and environmental risk factors. These risk factors modify hepatic metabolism and excretion of the DILI-causative agent leading to cellular stress, cell death, activation of an adaptive immune response and a failure to adapt, with progression to overt liver injury. Idiosyncratic DILI is a relative rare hepatic disorder but can be severe and, in some cases, fatal, presenting with a variety of phenotypes, which mimic other hepatic diseases. The diagnosis of DILI relies on the exclusion of other aetiologies of liver disease as specific biomarkers are still lacking. Clinical scales such as CIOMS/RUCAM can support the diagnostic process but need refinement. A number of clinical variables, validated in prospective cohorts, can be used to predict a more severe DILI outcome. Although no pharmacological therapy has been adequately tested in randomized clinical trials, corticosteroids can be useful, particularly in the emergent form of DILI related to immune-checkpoint inhibitors in patients with cancer.

Roussel Uclaf Causality Assessment Method for Drug-Induced Liver Injury: Present and Future

Among the causality assessment methods used for the diagnosis of drug-induced liver injury (DILI), Roussel Uclaf Causality Assessment Method (RUCAM) remains the most widely used not only for individual cases but also for prospective and retrospective studies worldwide. This first place is justified by the characteristics of the method such as precise definition and classification of the liver injury, which determines the right scale in the scoring system, precise definition of the seven criteria, and the validation approach based on cases with positive rechallenge. RUCAM is used not only for any types of drugs but also for herbal medicines causing herb-induced liver injury, (HILI) and dietary supplements. In 2016, the updated RUCAM provided further specifications of criteria and instructions to improve interobserver variability. Although this method was criticized for criteria such as the age and alcohol consumption, recent consensus meeting of experts has recognized their value and recommended their incorporation into any method. While early studies searching for DILI in large databases especially in electronic medical records were based on codes of diseases or natural language without causality assessment, the recommendation is now to include RUCAM in the search for DILI/HILI. There are still studies on DILI detection or the identification of biomarkers that take into consideration the cases assessed as “possible,” although it is well known that these cases reduce the strength of the association between the cases and the offending compound or the new biomarker to be validated. Attempts to build electronic RUCAM or automatized application of this method were successful despite some weaknesses to be corrected. In the future, more reflections are needed on an expert system to standardize the exclusion of alternative causes according to the clinical context. Education and training on RUCAM should be encouraged to improve the results of the studies and the day-to-day work in pharmacovigilance departments in companies or in regulatory agencies. It is also expected to improve RUCAM with biomarkers or other criteria provided that the validation process replaces expert opinion by robust standards such as those used for the original method.

Idiosyncratic DILI: Analysis of 46,266 Cases Assessed for Causality by RUCAM and Published From 2014 to Early 2019

One of the most difficult challenges in clinical hepatology is the diagnosis of a drug-induced liver injury (DILI). The timing of the events, exclusion of alternative causes, and taking into account the clinical context should be systematically assessed and scored in a transparent manner. RUCAM (Roussel Uclaf Causality Assessment Method) is a well-established diagnostic algorithm and scale to assess causality in patients with suspected DILI. First published in 1993 and updated in 2016, RUCAM is now the worldwide most commonly used causality assessment method (CAM) for DILI. The following manuscript highlights the recent implementation of RUCAM around the world, by reviewing the literature for publications that utilized RUCAM, and provides a review of “best practices” for the use of RUCAM in cases of suspected DILI. The worldwide appreciation of RUCAM is substantiated by the current analysis of 46,266 DILI cases, all tested for causality using RUCAM. These cases derived from 31 reports published from 2014 to early 2019. Their first authors came from 10 countries, with China on top, followed by the US, and Germany on the third rank. Importantly, all RUCAM-based DILI reports were published in high profile journals. Many other reports were published earlier from 1993 up to 2013 in support of RUCAM. Although most of the studies were of high quality, the current case analysis revealed shortcomings in few studies, not at the level of RUCAM itself but rather associated with the work of the users. To ensure in future DILI cases a better performance by the users, a list of essential elements is proposed. As an example, all suspected DILI cases should be evaluated 1) by the updated RUCAM to facilitate result comparisons, 2) according to a prospective study protocol to ensure complete data sets, 3) after exclusion of cases with herb induced liver injury (HILI) from a DILI cohort to prevent confounding variables, and 4) according to inclusion of DILI cases with RUCAM-based causality gradings of highly probable or probable, in order to increase the specificity of the results. In conclusion, RUCAM benefits from its high appreciation and performs well provided the users adhere to published recommendations to prevent confounding variability.

Roussel Uclaf Causality Assessment Method for Drug-Induced Liver Injury: Present and Future

Among the causality assessment methods used for the diagnosis of drug-induced liver injury (DILI), Roussel Uclaf Causality Assessment Method (RUCAM) remains the most widely used not only for individual cases but also for prospective and retrospective studies worldwide. This first place is justified by the characteristics of the method such as precise definition and classification of the liver injury, which determines the right scale in the scoring system, precise definition of the seven criteria, and the validation approach based on cases with positive rechallenge. RUCAM is used not only for any types of drugs but also for herbal medicines causing herb-induced liver injury, (HILI) and dietary supplements. In 2016, the updated RUCAM provided further specifications of criteria and instructions to improve interobserver variability. Although this method was criticized for criteria such as the age and alcohol consumption, recent consensus meeting of experts has recognized their value and recommended their incorporation into any method. While early studies searching for DILI in large databases especially in electronic medical records were based on codes of diseases or natural language without causality assessment, the recommendation is now to include RUCAM in the search for DILI/HILI. There are still studies on DILI detection or the identification of biomarkers that take into consideration the cases assessed as "possible," although it is well known that these cases reduce the strength of the association between the cases and the offending compound or the new biomarker to be validated. Attempts to build electronic RUCAM or automatized application of this method were successful despite some weaknesses to be corrected. In the future, more reflections are needed on an expert system to standardize the exclusion of alternative causes according to the clinical context. Education and training on RUCAM should be encouraged to improve the results of the studies and the day-to-day work in pharmacovigilance departments in companies or in regulatory agencies. It is also expected to improve RUCAM with biomarkers or other criteria provided that the validation process replaces expert opinion by robust standards such as those used for the original method.

Idiosyncratic DILI: Analysis of 46,266 Cases Assessed for Causality by RUCAM and Published From 2014 to Early 2019

One of the most difficult challenges in clinical hepatology is the diagnosis of a drug-induced liver injury (DILI). The timing of the events, exclusion of alternative causes, and taking into account the clinical context should be systematically assessed and scored in a transparent manner. RUCAM (Roussel Uclaf Causality Assessment Method) is a well-established diagnostic algorithm and scale to assess causality in patients with suspected DILI. First published in 1993 and updated in 2016, RUCAM is now the worldwide most commonly used causality assessment method (CAM) for DILI. The following manuscript highlights the recent implementation of RUCAM around the world, by reviewing the literature for publications that utilized RUCAM, and provides a review of "best practices" for the use of RUCAM in cases of suspected DILI. The worldwide appreciation of RUCAM is substantiated by the current analysis of 46,266 DILI cases, all tested for causality using RUCAM. These cases derived from 31 reports published from 2014 to early 2019. Their first authors came from 10 countries, with China on top, followed by the US, and Germany on the third rank. Importantly, all RUCAM-based DILI reports were published in high profile journals. Many other reports were published earlier from 1993 up to 2013 in support of RUCAM. Although most of the studies were of high quality, the current case analysis revealed shortcomings in few studies, not at the level of RUCAM itself but rather associated with the work of the users. To ensure in future DILI cases a better performance by the users, a list of essential elements is proposed. As an example, all suspected DILI cases should be evaluated 1) by the updated RUCAM to facilitate result comparisons, 2) according to a prospective study protocol to ensure complete data sets, 3) after exclusion of cases with herb induced liver injury (HILI) from a DILI cohort to prevent confounding variables, and 4) according to inclusion of DILI cases with RUCAM-based causality gradings of highly probable or probable, in order to increase the specificity of the results. In conclusion, RUCAM benefits from its high appreciation and performs well provided the users adhere to published recommendations to prevent confounding variability.