Resolution of norfloxacin-induced acute liver failure after N-acetylcysteine therapy: further support for the use of NAC in drug-induced ALF?

The Use and Potential Benefits of N-Acetylcysteine in Non-Acetaminophen Acute Liver Failure: An Etiology-Based Review

Acute liver failure represents a life-threatening organ dysfunction with high mortality rates and an urgent need for liver transplantation. The etiology of the disease varies widely depending on various socio-economic factors and is represented mainly by paracetamol overdose and other drug-induced forms of liver dysfunction in the developed world and by viral hepatitis and mushroom poisoning in less developed countries. Current medical care constitutes either specific antidotes or supportive measures to ensure spontaneous recovery. Although it has been proven to have beneficial effects in paracetamol-induced liver failure, N-acetylcysteine is widely used for all forms of acute liver failure. Despite this, few well-designed studies have been conducted on the assessment of the potential benefits, dose regimens, or route of administration of N-acetylcysteine in non-acetaminophen liver failure. This review aims to summarize the current evidence behind the use of this drug in different forms of liver failure.

Clinical characteristics and prognosis of non-APAP drug-induced acute liver failure: a large multicenter cohort study

BACKGROUND

There is growing recognition of natural history, complications, and outcomes of patients who develop non-acetaminophen (APAP) drug-induced acute liver failure (ALF). To clarify high-risk factors and develop a nomogram model to predict transplant-free survival (TFS) in patients with non-APAP drug-induced ALF.

METHODS

Patients with non-APAP drug-induced ALF from 5 participating centers were retrospectively analyzed. The primary endpoint was 21-day TFS. Total sample size was 482 patients.

RESULTS

Regarding causative agents, the most common implicated drugs were herbal and dietary supplements (HDS) (57.0%). The hepatocellular type (R ≥ 5) was the main liver injury pattern (69.0%). International normalized ratio, hepatic encephalopathy grades, the use of vasopressor, N-acetylcysteine, or artificial liver support system were associated with TFS and incorporated to construct a nomogram model (drug-induced acute liver failure-5, DIALF-5). The AUROC of DIALF-5 for 7-day, 21-day, 60-day, and 90-day TFS in the internal cohort were 0.886, 0.915, 0.920, and 0.912, respectively. Moreover, the AUROC of DIALF-5 for 21-day TFS had the highest AUROC, which was significantly higher than 0.725 of MELD and 0.519 of KCC (p < 0.05), numerically higher than 0.905 of ALFSG-PI but without statistical difference (p > 0.05). These results were successfully validated in the external cohort (147 patients).

CONCLUSIONS

Based on easily identifiable clinical data, the novel DIALF-5 model was developed to predict transplant-free survival in non-APAP drug-induced ALF, which was superior to KCC, MELD and had a similar prediction performance to ALFSG-PI but is more convenient, which can directly calculate TFS at multiple time points.

N-acetylcysteine for non-acetaminophen induced acute liver failure: A review

The use of N-acetylcysteine (NAC) for non-acetaminophen-induced acute liver failure (NAI-ALF) has been increasing despite controversy in its efficacy. National guidelines are in disagreement for NAC use as standard of care; however, many healthcare centers continue to adopt the use of NAC outside of acetaminophen poisoning. While NAC may have multiple mechanisms of action in treatment of ALF, this has not translated to clinical benefit. Murine models have reported antioxidant and anti-inflammatory properties, as well as improvement in liver-specific microcirculation. Multiple case studies and series have reported positive outcomes of NAC treatment for ALF of various etiologies. While prospective studies suggested the benefit of NAC treatment, these studies have methodological and statistical shortcomings that affect the validity of the results. In this review, we aimed to summarize the existing literature on the efficacy of NAC for NAI-ALF including mechanism of action, case studies and series demonstrating outcomes, and prospective studies that have led to its current widespread use, along with the reported rate of adverse events.

Pharmacotherapies for Drug-Induced Liver Injury: A Current Literature Review

Drug-induced liver injury (DILI) has become a serious public health problem. For the management of DILI, discontinuation of suspicious drug or medicine is the first step, but the treatments including drugs and supporting approaches are needed. Reference to clinical patterns and disease severity grades of DILI, the treatment drugs were considered to summarize into hepatoprotective drugs (N-acetylcysteine and Glutathione, Glycyrrhizin acid preparation, Polyene phosphatidylcholine, Bicyclol, Silymarin), anticholestatic drug (Ursodeoxycholic acid, S-adenosylmethionine, Cholestyramine), immunosuppressants (Glucocorticoids) and specific treatment agents (L-carnitine, Anticoagulants). The current article reviewed the accumulated literature with evidence-based medicine researches for DILI in clinical practice. Also the drawbacks of the clinical studies involved in the article, unmet needs and prospective development for DILI therapy were discussed.

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.

S-allyl-L-cysteine protects hepatocytes from indomethacin-induced apoptosis by attenuating endoplasmic reticulum stress

Drug‐induced liver injury (DILI) can lead to acute liver failure, a lethal condition which may require liver transplantation. Hepatotoxicity associated with nonsteroidal anti‐inflammatory drugs (NSAIDs) accounts for ~ 10% of all DILI. In the current study, we determined whether indomethacin, one of the most commonly used NSAIDS, induced apoptosis in hepatocytes and investigated the underlying mechanism. Meanwhile, we investigated the protective effect of S‐allyl‐L‐cysteine (SAC), an active garlic derivative, on indomethacin‐induced hepatocyte apoptosis, and its implication on endoplasmic reticulum (ER) stress. We found that indomethacin triggered ER stress, as indicated by the elevated expression of phosphorylated eukaryotic translation initiation factor 2α (eIF2α), C/EBP homologous protein (CHOP) and spliced XBP1 in a rat liver BRL‐3A cell line. Following indomethacin treatment, caspase 3 activation and hepatocyte apoptosis were also observed. Inhibition of ER stress by chemical chaperone 4‐phenyl butyric acid alleviated cell apoptosis caused by indomethacin, indicating that ER stress is involved in indomethacin‐induced hepatocyte apoptosis. Moreover, SAC abated indomethacin‐induced eIF2α phosphorylation, inhibited CHOP upregulation and its nuclear translocation, abrogated the activation of caspase 3 and finally, protected hepatocytes from apoptosis. In conclusion, SAC protects indomethacin‐induced hepatocyte apoptosis through mitigating ER stress and may be suitable for development into a potential new therapeutic agent for the treatment of DILI.

Drug-induced liver injury due to antibiotics

Drug-induced liver injury (DILI) is an important differential diagnosis in patients with abnormal liver tests and normal hepatobiliary imaging. Of all known liver diseases, the diagnosis of DILI is probably one of the most difficult one to be established. In all major studies on DILI, antibiotics are the most common type of drugs that have been reported. The clinical phenotype of different types of antibiotics associated with liver injury is highly variable. Some widely used antibiotics such as amoxicillin-clavulanate have been shown to have a delayed onset on liver injury and recently cefazolin has been found to lead to liver injury 1-3 weeks after exposure of a single infusion. The other extreme is the nature of nitrofurantoin-induced liver injury, which can occur after a few years of treatment and lead to acute liver failure (ALF) or autoimmune-like reaction. Most patients with liver injury associated with use of antibiotics have a favorable prognosis. However, patients with jaundice have approximately 10% risk of death from liver failure and/or require liver transplantation. In rare instances, the hepatoxicity can lead to chronic injury and vanishing bile duct syndrome. Given, sometimes very severe consequences of the adverse liver reactions, it cannot be over emphasized that the indication for the different antibiotics should be evidence-based and symptoms and signs of liver injury from the drugs should lead to prompt cessation of therapy.