Idiosyncratic drug-induced liver injury (IDILI) is a rare but potentially severe adverse drug reaction that should be considered in patients who develop laboratory criteria for liver injury secondary to the administration of a potentially hepatotoxic drug. Although currently used liver parameters are sensitive in detecting DILI, they are neither specific nor able to predict the patient's subsequent clinical course. Genetic risk assessment is useful mainly due to its high negative predictive value, with several human leucocyte antigen alleles being associated with DILI. New emerging biomarkers which could be useful in assessing DILI include total keratin18 (K18) and caspase-cleaved keratin18 (ccK18), macrophage colony-stimulating factor receptor 1, high mobility group box 1 and microRNA-122. From the numerous in vitro test systems that are available, monocyte-derived hepatocytes generated from patients with DILI show promise in identifying the DILI-causing agent from among a panel of coprescribed drugs. Several computer-based algorithms are available that rely on cumulative scores of known risk factors such as the administered dose or potential liabilities such as mitochondrial toxicity, inhibition of the bile salt export pump or the formation of reactive metabolites. A novel DILI cluster score is being developed which predicts DILI from multiple complimentary cluster and classification models using absorption–distribution–metabolism–elimination-related as well as physicochemical properties, diverse substructural descriptors and known structural liabilities. The provision of more advanced scientific and regulatory guidance for liver safety assessment will depend on validating the new diagnostic markers in the ongoing DILI registries, biobanks and public–private partnerships.
The steroid hormone aldosterone is important for salt and water homeostasis as well as for pathological tissue modifications in the cardiovascular system and the kidney. The mechanisms of action include a classical genomic pathway, but physiological relevant nongenotropic effects have also been described. Unlike for estrogens or progesterone, the mechanisms for these nongenotropic effects are not well understood, although pharmacological studies suggest a role for the mineralocorticoid receptor (MR). Here we investigated whether the MR contributes to nongenotropic effects. After transfection with human MR, aldosterone induced a rapid and dose-dependent phosphorylation of ERK1/2 and c-Jun NH2-terminal kinase (JNK) 1/2 kinases in Chinese hamster ovary or human embryonic kidney cells, which was reduced by the MR-antagonist spironolactone and involved cSrc kinase as well as the epidermal growth factor receptor. In primary human aortic endothelial cells, similar results were obtained for ERK1/2 and JNK1/2. Inhibition of MAPK kinase (MEK) kinase but not of protein kinase C prevented the rapid action of aldosterone and also reduced aldosterone-induced transactivation, most probably due to impaired nuclear-cytoplasmic shuttling of MR. Cytosolic Ca2+ was increased by aldosterone in mock- and in human MR-transfected cells to the same extend due to Ca2+ influx, whereas dexamethasone had virtually no effect. Spironolactone did not prevent the Ca2+ response. We conclude that some nongenotropic effects of aldosterone are MR dependent and others are MR independent (e.g. Ca2+), indicating a higher degree of complexity of rapid aldosterone signaling. According to this model, we have to distinguish three aldosterone signaling pathways: 1) genomic via MR, 2) nongenotropic via MR, and 3) nongenotropic MR independent.
The development of acute‐on‐chronic liver failure (ACLF) in patients with liver cirrhosis is associated with high mortality rates. Renal failure is the most significant organ dysfunction that occurs in ACLF. So far there are no biomarkers predicting ACLF. We investigated whether cystatin C (CysC) and neutrophil gelatinase‐associated lipocalin (NGAL) can predict development of renal dysfunction (RD), hepatorenal syndrome (HRS), ACLF, and mortality. We determined the plasma levels of CysC and NGAL in 429 patients hospitalized for acute decompensation of cirrhosis in the EASL‐CLIF Acute‐on‐Chronic Liver Failure in Cirrhosis (CANONIC) study. The patients were followed for 90 days. Patients without RD or ACLF at inclusion but with development of either had significantly higher baseline concentrations of CysC and NGAL compared to patients without. CysC, but not NGAL, was found to be predictive of RD (odds ratio, 9.4; 95% confidence interval [CI], 1.8‐49.7), HRS (odds ratio, 4.2; 95% CI, 1.2‐14.8), and ACLF (odds ratio, 5.9; 95% CI, 1.3‐25.9). CysC at day 3 was not found to be a better predictor than baseline CysC. CysC and NGAL were both predictive of 90‐day mortality, with hazard ratios for CysC of 3.1 (95% CI, 2.1‐4.7) and for NGAL of 1.9 (95% CI, 1.5‐2.4). Conclusion: Baseline CysC is a biomarker of RD, HRS, and ACLF and an independent predictor of mortality in patients with acutely decompensated liver cirrhosis, though determining CysC at day 3 did not provide any benefit; while NGAL is also associated with short‐term mortality, it fails to predict development of RD, HRS, and ACLF. Baseline CysC may help to identify patients at risk earlier and improve clinical management. (Hepatology 2017;66:1232‐1241)
Background: Drug‐induced liver injury (DILI) and idiopathic autoimmune hepatitis (AIH) are competing diagnoses in patients with acute liver injury (ALI) and drug intake. In absence of unequivocal markers, scores like RUCAM and AIH are used to distinguish both entities. However, in some cases the diagnosis remains ambiguous. Our aim was to identify a simple parameter to discriminate DILI and AIH shortly after starting corticosteroid treatment.Methods: For the current analysis, 44 patients with ALI who took at least one drug and who received corticosteroids were included and comprised 22 DILI and 22 AIH cases. Scores of AIH and RUCAM were calculated at initial presentation, the final diagnosis was made from analysing the course of disease. Changes in the serum alanine aminotransferase (ALT) concentrations after starting corticosteroid treatment were determined and compared between the DILI and AIH groups.Results: Fifty‐nine per cent of patients (n = 26) were correctly classified at presentation by AIH score and RUCAM respectively. However, in one‐third (n = 13) of the 44 patients, results were inconclusive and five other patients were misclassified. The decrease in ALT levels 1 week after the initiation of steroid therapy was significantly more pronounced in patients with the final diagnosis of DILI than in AIH patients (accuracy 77%). This difference was also observed in the 18 initially misclassified or inconclusive cases (accuracy 83%).Conclusion: Short‐term response of ALT to corticosteroid therapy helps to differentiate DILI and AIH. This finding may be helpful in treatment decision for patients with inconclusive diagnostic scores.