Evaluation of diagnostic and prognostic candidate biomarkers in drug-induced liver injury versus other forms of acute liver damage

AIMS

Detection and characterization of idiosyncratic drug-induced liver injury (DILI) currently relies on standard liver tests, which are suboptimal in terms of specificity, sensitivity and prognosis. Therefore, DILI diagnosis can be delayed, with important consequences for the patient. In this study we aimed to evaluate the potential of osteopontin, cytokeratin-18 (caspase-cleaved: ccK18 and total: K18), α-glutathione-S-transferase and microRNA-122 as new DILI biomarkers.

METHODS

Serial blood samples were collected from 32 DILI and 34 non-DILI acute liver injury (ALI) cases and a single sample from 43 population controls without liver injury (HLC) and analysed using ELISA assays or single-molecule arrays.

RESULTS

All biomarkers differentiated DILI and ALI from HLC with an area under receiver operator characteristic curve (AUC) value >0.75, but were less efficient in distinguishing DILI from ALI, with ccK18 (0.79) and K18 (0.76) demonstrating highest potential. However, the AUC improved considerably (0.98) for ccK18 when comparing DILI and a subgroup of autoimmune hepatitis cases. Cytokeratin-18, microRNA-122 and α-glutathione-S-transferase correlated well with traditional transaminases, while osteopontin was strongest correlated with INR.

CONCLUSION

ccK18 appears promising in distinguishing DILI from autoimmune hepatitis, but less so from other forms of acute liver injury. Osteopontin demonstrates prognostic potential with higher levels detected in more severe cases regardless of aetiology.

Lymphocyte Profile and Immune Checkpoint Expression in Drug-Induced Liver Injury: An Immunophenotyping Study

The identification of specific HLA risk alleles in drug-induced liver injury (DILI) points toward an important role of the adaptive immune system in DILI development. In this study, we aimed to corroborate the role of an adaptive immune response in DILI through immunophenotyping of leukocyte populations and immune checkpoint expressions. Blood samples were collected from adjudicated DILI (n = 12), acute viral hepatitis (VH; n = 13), acute autoimmune hepatitis (AIH; n = 9), and acute liver injury of unknown etiology (n = 15) at day 1 (recognition), day 7, and day >30. Blood samples from patients with nonalcoholic fatty liver disease (NAFLD; n = 20) and healthy liver controls (HLCs; n = 54) were extracted at one time point. Leukocyte populations and immune checkpoint expressions were determined based on cell surface receptors, except for CTLA-4 that was determined intracellularly, using flow cytometry. At recognition, DILI demonstrated significantly higher levels of activated helper T-cell (P < 0.0001), activated cytotoxic T-cells (P = 0.0003), Th1 (P = 0.0358), intracellular CTLA-4 level in helper T-cells (P = 0.0192), and PD-L1 presenting monocytes (P = 0.0452) than HLC. These levels approached those of HLC over time. No significant differences were found between DILI and VH. However, DILI presented higher level of activated helper T-cells and CTLA-4 than NAFLD and lower PD-L1 level than AIH. Our findings suggest that an adaptive immune response is involved in DILI in which activated CD4+ and CD8+ play an important role. Increased expression of negative immune checkpoints is likely the effect of peripheral tolerance regulation.

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.

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.

Hepatic Damage by Natural Remedies

The rising burden of herbal and dietary supplement hepatotoxicity (HILI) is a growing concern in Western countries. The estimated incidence of HILI in well-designed prospective studies ranges from less than 1 to 3 individuals per 100,000 inhabitants/year. Herbal hepatotoxicity has a particular signature encompassing female predominance, hepatocellular type of damage with markedly elevated transaminases on presentation, more common unintentional rechallenge, and a greater risk of death/liver transplantation. Herbal hepatotoxicity recognition is particularly challenging for hepatologists because of the often hidden herbal consumption, difficulties in identifying the causative herbal component, and the possibility of contamination, adulteration, and misidentification, which preclude a proper adjudication and lead to inaccurate reporting of cases in scientific journals. Collaborative efforts to retrieve detailed phenotypic data and biological samples of patients with HILI would facilitate genomic and other molecular approaches for a better understanding of host risk factors and, hopefully, for biomarker identification.

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

BACKGROUND & AIMS

Chronic 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.

METHODS

298 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.

RESULTS

Out 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.

CONCLUSIONS

One 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.

LAY SUMMARY

Drug-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

BACKGROUND & AIMS

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.

METHODS

Clinical, laboratory and histological data from 588 DILI episodes included in the Spanish DILI Registry were analyzed. Linear regression analysis was performed to establish the most appropriate cut-off points for hepatocellular and cholestatic patterns when calculating R with AST and GGT.

RESULTS

The overall agreement between ALT/ALP and AST/ALP was 76%, with 96%, 61% and 41% agreement in the hepatocellular (R ≥ 5), cholestatic (R ≤ 2) and mixed groups respectively (P < 0.001). Classified by the causative drug, the agreement was higher (87-95%) among drug classes that mainly present with hepatocellular damage and lower (48-58%) for those in which cholestatic-mixed injury predominate (P < 0.001)). The overall agreement between ALT/ALP and ALT/GGT was weak (59%), except for in hepatocellular cases that showed a good agreement (94%) (P = 0.001). Pattern of injury according to liver histology demonstrated 65%, 68% and 47% agreement for ALT/ALP, AST/ALP and ALT/GGT ratios respectively.

CONCLUSIONS

AST can reliably replace ALT when calculating pattern of liver injury in DILI, while GGT can only substitute ALP when the R value scores as hepatocellular. The biochemical signature of causative drugs does influence the validity of the ratios with AST or GGT.