Interventions for paracetamol (acetaminophen) overdose

Deciphering per- and polyfluoroalkyl substances mode of action: comparative gene expression analysis in human liver spheroids

Understanding the mechanisms by which environmental chemicals cause toxicity is necessary for effective human health risk assessment. High-throughput transcriptomics (HTTr) can be used to inform risk assessment on toxicological mechanisms, hazards, and potencies. We applied HTTr to elucidate the molecular mechanisms by which per- and polyfluoroalkyl substances (PFAS) cause liver perturbations. We contrasted transcriptomic profiles of PFOA, PFBS, PFOS, and PFDS against transcriptomic profiles from established liver-toxic and non-toxic reference compounds, alongside peroxisome proliferator-activated receptors (PPARs) agonists. Our analysis was conducted on metabolically competent 3-D human liver spheroids produced from primary cells from 10 donors. Pathway analysis showed that PFOS and PFDS perturb many of the same pathways as the known liver-toxic compounds in the spheroids, and that the cholesterol biosynthesis pathways are significantly affected by exposure to these compounds. PFOA alters lipid metabolism-related pathways but its expression profile does not closely match reference compounds. PFBS upregulates many degradation-related pathways and targets many of the same pathways as the PPAR agonists and acetaminophen. Our transcriptional analysis does not support the claim that these PFAS are DNA-damaging in this model. A multidimensional scaling (MDS) analysis revealed that PFOS, PFOA, and PFDS cluster together in the same multidimensional space as liver-damaging compounds, whereas PFBS clusters more closely with the non-liver-damaging compounds. Benchmark concentration-response modeling predicts that all the PFAS are bioactive in the liver. Overall, our results show that these PFAS produce unique transcriptional changes but also alter pathways associated with established liver-toxic chemicals in this liver spheroid model.

Mogroside V protects against acetaminophen-induced liver injury by reducing reactive oxygen species and c-jun-N-terminal kinase activation in mice

BACKGROUND

High levels of acetaminophen (APAP) consumption can result in significant liver toxicity. Mogroside V (MV) is a bioactive, plant-derived triterpenoid known for its various pharmacological activities. However, the impact of MV on acute liver injury (ALI) is unknown.

AIM

To investigate the hepatoprotective potential of MV against liver damage caused by APAP and to examine the underlying mechanisms.

METHODS

Mice were divided into three groups: Saline, APAP and APAP + MV. MV (10 mg/kg) was given intraperitoneally one hour before APAP (300 mg/kg) administration. Twenty-four hours after APAP exposure, serum transaminase levels, liver necrotic area, inflammatory responses, nitrotyrosine accumulation, and c-jun-N-terminal kinase (JNK) activation were assessed. Additionally, we analyzed reactive oxygen species (ROS) levels, JNK activation, and cell death in alpha mouse liver 12 (AML12) cells.

RESULTS

MV pre-treatment in vivo led to a reduction in the rise of aspartate transaminase and alanine transaminase levels, mitigated liver damage, decreased nitrotyrosine accumulation, and blocked JNK phosphorylation resulting from APAP exposure, without affecting glutathione production. Similarly, MV diminished the APAP-induced increase in ROS, JNK phosphorylation, and cell death in vitro.

CONCLUSION

Our study suggests that MV treatment alleviates APAP-induced ALI by reducing ROS and JNK activation.

The effect of acetylcysteine on the prothrombin time and international normalized ratio: a narrative review

INTRODUCTION

Patients poisoned with paracetamol are treated with acetylcysteine. In patients without hepatocellular injury, an increased prothrombin time or international normalized ratio has been observed during acetylcysteine administration. The international normalized ratio is preferred as it is a standardized calculation of prothrombin time independent of reagents and machinery. Since the prothrombin time and international normalized ratio are used as markers of liver injury in patients with paracetamol poisoning, it is important to assess the magnitude of the effect of acetylcysteine treatment on the prothrombin time and international normalized ratio. The aim of this narrative review is to describe the effect of acetylcysteine on the prothrombin time and international normalized ratio.

METHODS

Embase, PubMed and Web of Science were searched to identify the effect of acetylcysteine on coagulation factors II, VII, IX or X, the prothrombin time and the international normalized ratio in in vitro and in vivo studies in healthy subjects and clinical studies involving both those poisoned with paracetamol and surgical patients. The search terms employed were acetylcysteine combined with prothrombin time, international normalized ratio, coagulation or haemostasis.

RESULTS

The search identified a total of 2,471 articles, of which 19 studies were included. Six in vitro and/or in vivo studies, five clinical studies in paracetamol-poisoned patients and eight clinical studies in surgical patients were included. Acetylcysteine caused a 15-30% increase in prothrombin time and international normalized ratio. This increase was dose-dependent and was caused by a decrease in the activity of coagulation factors II, VII, IX and X. The effect of acetylcysteine on the increased prothrombin time and international normalized ratio was more prominent after the high loading dose but remained present during the lower maintenance dose of acetylcysteine. The effect was observed in both in vitro and in vivo studies and confirmed in clinical studies in paracetamol-poisoned patients without hepatic injury. Studies in surgical patients treated with acetylcysteine showed conflicting results. Twelve of the 13 clinical studies suffered from risk of bias, limiting the value of these studies.

DISCUSSION

The moderate 15-30% increase in the international normalized ratio induced by acetylcysteine is especially important in hospitals using the international normalized ratio as a marker for hepatotoxicity due to paracetamol poisoning and underlines the need for the international normalized ratio to be assessed at admission.

CONCLUSION

Acetylcysteine treatment leads to an estimated 15-30% increase in prothrombin time and international normalized ratio in both experimental studies and paracetamol-poisoned patients. Isolated increases in prothrombin time and international normalized ratio during acetylcysteine infusion are common and do not necessarily reflect liver dysfunction or liver injury.

[N-Acetylcysteine (NAC) for Retinitis pigmentosa]

Retinitis pigmentosa (RP) is a genetically mediated degenerative retinal disease that leads to progressive photoreceptor degeneration and, ultimately, blindness. Oxidative stress plays a central role in the pathogenesis of RP. This study examines the effect of N-acetylcysteine (NAC), an antioxidant and glutathione precursor, on the disease progression in RP patients. NAC can reduce oxidative stress in the retina and has shown potential neuroprotective effects in preclinical models. Initial clinical studies indicate improvements in visual acuity and macular function with NAC therapy, though no structural changes have yet been demonstrated. The ongoing multicentre Phase III trial "NAC Attack" aims to evaluate the long-term efficacy and safety of NAC in RP.

Comparison of two-bag and three-bag acetylcysteine regimens in the treatment of paracetamol poisoning: a systematic review and meta-analysis

INTRODUCTION

Worldwide, paracetamol poisoning is a common cause of acute liver failure and referral to transplant centers. Acetylcysteine has long been the mainstay of treatment, but recent literature suggests that a simplification of the "three-bag" method may decrease adverse effects. Our primary hypothesis is that a simplified dosing regimen (two-bag regimen) is non-inferior to the three-bag method in preventing liver injury. Our secondary hypothesis is that a simplified regimen will have lower rates of adverse effects.

METHODS

Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched Medline/PubMed, Google, Google Scholar, Cochrane Library, Embase and Toxnet on May 23, 2022. The Medical Subject Headings terms were NAC, acetaminophen toxicity, acetyl-cysteine, N-acetylcysteine, paracetamol, APAP, 2-bag, and 3-bag. The Embase terms were acetylcysteine, NAC, 2-bag, two bag, 3-bag, three bag, simplified dosing, acetaminophen, Tylenol®, paracetamol, APAP, drug overdose, poisoning, and overdose. Studies included both non-United States Food and Drug Administration-approved and United States Food and Drug Administration-approved acetylcysteine regimens. Case reports, review articles, and animal studies were excluded. Two authors independently reviewed each study using Rayyan QCRI to determine if the studies met search criteria while blinded to the selections of each other. The two authors discussed until reaching a consensus. We used a primary outcome of non-inferiority of hepatotoxicity. We used secondary outcomes of non-allergic anaphylactoid reactions and adverse events. We conducted a fixed-effect meta-analysis using R package meta. To visually summarize the meta-analysis results, we also produced forest plots. We used Cochran's Q test and I2 statistical analysis to assess heterogeneity between the studies.

RESULTS

Our search resulted in 657 total citations, which were reduced to unique citations. Of the 643 studies, 46 met the criteria for full text review, and eight met the study criteria. Of the eight studies investigating a simplified acetylcysteine regimen, four studies utilized some form of a modified two-bag infusion regimen, varying in duration or dosing of infusions, and four studies shared the same "common" two-bag treatment, a regimen that delivers acetylcysteine 200 mg/kg over 4 h, followed by 100 mg/kg acetylcysteine over 16 h. The six studies comparing a two-bag dosing regimen to the three-bag technique were utilized for our random effect model meta-analysis. We found no significant heterogeneity amongst the six studies for either hepatotoxicity (Q(5) = 1.11; P = 0.95; I2 = 0%; 95% CI: 0%-74.6%) or non-allergic anaphylactoid reactions and adverse events (Q(5) = 10.15; P = 0.07; I2 = 50.7%; 95% CI: 0%-80.4%). Compared to the traditional three-bag dosing regimen, the two-bag method did not demonstrate a difference in relative risk for hepatotoxicity (OR: 0.88; 95% CI: 0.72-1.08; P = 0.23) but did demonstrate a significantly decreased likelihood of non-allergic anaphylactoid reactions and other adverse events (OR: 0.24; 95% CI: 0.17-0.35; P <0.0001).

DISCUSSION

The two-bag method is a safe and effective treatment for acute paracetamol poisoning. The two-bag regimen is correlated with a significant reduction in non-allergic anaphylactoid reactions, compared to the three-bag method, and is non-inferior with respect to hepatotoxicity. While we feel this information is practice changing for many, further research in the form of a randomized control trial would be beneficial to compare even more abbreviated methods such as a "single bag method."

CONCLUSION

Two-bag acetylcysteine dosing regimens appear to be non-inferior to the three-bag method with respect to hepatotoxicity, and result in fewer anaphylactoid, cutaneous, and gastrointestinal reactions.

Emerging Roles of High-mobility Group Box-1 in Liver Disease

High-mobility group box-1 (HMGB1) is an architectural chromosomal protein with various roles depending on its cellular localization. Extracellular HMGB1 functions as a prototypical damage-associated molecular pattern that triggers inflammation and adaptive immune responses, mediated by specific cell surface receptors, including receptors for advanced glycation end products and toll-like receptors. Post-translational modifications of HMGB1 significantly impact various cellular processes that contribute to the pathogenesis of liver diseases. Recent studies have highlighted the close relationship between HMGB1 and the pathogenesis of acute liver injuries, including acetaminophen-induced liver injury, hepatic ischemia-reperfusion injury, and acute liver failure. In chronic liver diseases, HMGB1 plays a role in nonalcoholic fatty liver disease, alcohol-associated liver disease, liver fibrosis, and hepatocellular carcinoma. Targeting HMGB1 as a therapeutic approach, either by inhibiting its release or blocking its extracellular function, is a promising strategy for treating liver diseases. This review aimed to summarize the available evidence on HMGB1's role in liver disease, focusing on its multifaceted signaling pathways, impact on disease progression, and the translation of these findings into clinical interventions.

Macrophage manufacturing and engineering with 5'-Cap1 and N1-methylpseudouridine-modified mRNA

Macrophage-based cell therapeutics is an emerging modality to treat cancer and repair tissue damage. A reproducible manufacturing and engineering process is central to fulfilling their therapeutic potential. Here, we establish a robust macrophage-manufacturing platform (Mo-Mac) and demonstrate that macrophage functionality can be enhanced by N1-methylpseudouridine (m1Ψ)-modified mRNA. Using single-cell transcriptomic analysis as an unbiased approach, we found that >90% cells in the final product were macrophages while the rest primarily comprised T cells, B cells, natural killer cells, promyelocytes, promonocytes, and hematopoietic stem cells. This analysis also guided the development of flow-cytometry strategies to assess cell compositions in the manufactured product to meet requirements by the National Medical Products Administration. To modulate macrophage functionality, as an illustrative example we examined whether the engulfment capability of macrophages could be enhanced by mRNA technology. We found that efferocytosis was increased in vitro when macrophages were electroporated with m1Ψ-modified mRNA encoding CD300LF (CD300LF-mRNA-macrophage). Consistently, in a mouse model of acute liver failure, CD300LF-mRNA-macrophages facilitated organ recovery from acetaminophen-induced hepatotoxicity. These results demonstrate a GMP-compliant macrophage-manufacturing process and indicate that macrophages can be engineered by versatile mRNA technology to achieve therapeutic goals.

Liver regeneration after injury: Mechanisms, cellular interactions and therapeutic innovations

The liver possesses a distinctive capacity for regeneration within the human body. Under normal circumstances, liver cells replicate themselves to maintain liver function. Compensatory replication of healthy hepatocytes is sufficient for the regeneration after acute liver injuries. In the late stage of chronic liver damage, a large number of hepatocytes die and hepatocyte replication is blocked. Liver regeneration has more complex mechanisms, such as the transdifferentiation between cell types or hepatic progenitor cells mediated. Dysregulation of liver regeneration causes severe chronic liver disease. Gaining a more comprehensive understanding of liver regeneration mechanisms would facilitate the advancement of efficient therapeutic approaches. This review provides an overview of the signalling pathways linked to different aspects of liver regeneration in various liver diseases. Moreover, new knowledge on cellular interactions during the regenerative process is also presented. Finally, this paper explores the potential applications of new technologies, such as nanotechnology, stem cell transplantation and organoids, in liver regeneration after injury, offering fresh perspectives on treating liver disease.

Fifty years of paracetamol (acetaminophen) poisoning: the development of risk assessment and treatment 1973-2023 with particular focus on contributions published from Edinburgh and Denver

INTRODUCTION

Fifty years ago, basic scientific studies and the availability of assay methods made the assessment of risk in paracetamol (acetaminophen) poisoning possible. The use of the antidote acetylcysteine linked to new methods of risk assessment transformed the treatment of this poisoning. This review will describe the way in which risk assessment and treatments have developed over the last 50 years and highlight the remaining areas of uncertainty.

METHODS

A search of PubMed and its subsidiary databases revealed 1,166 references published in the period 1963-2023 using the combined terms "paracetamol", "poisoning", and "acetylcysteine". Focused searches then identified 170 papers dealing with risk assessment of paracetamol poisoning, 141 with adverse reactions to acetylcysteine and 114 describing different acetylcysteine regimens. To manage the extensive literature, we focused mainly on contributions made by the authors during their time in Edinburgh and Denver.

DOSE AND CONCENTRATION RESPONSE

The key relationship between paracetamol dose and toxicity risk was established in 1971 and led to the development of the Rumack-Matthew nomogram from data collected in Edinburgh.

MECHANISMS OF TOXICITY

A series of papers on the mechanisms of toxicity were published in 1973, and these showed that paracetamol hepatotoxicity was caused by the formation of a toxic intermediate epoxide metabolite normally detoxified by glutathione but which, in excess, was bound covalently to hepatic enzymes and proteins. An understanding of the relationship between the rate of paracetamol metabolism, paracetamol concentration, and toxic hazard in humans soon followed.

ANTIDOTE DEVELOPMENT AND EFFICACY IN PATIENTS

These discoveries were followed by the testing of a range of sulfhydryl-donors in animals and "at risk" patients. Acetylcysteine was developed as the lead intravenous antidote in the United Kingdom. The license holder in the United States refused to make an intravenous formulation. Thus, oral acetylcysteine became the antidote trialed in the United States National Multicenter Study. Intravenous acetylcysteine regimens used initially in the United Kingdom and subsequently in the United States used loading doses of 150 mg/kg over 15 minutes or one hour, 50 mg/kg over four hours, and 100 mg/kg over 16 hours. These regimens were associated with adverse drug reactions (nausea, vomiting and anaphylactoid reactions) and hence, treatment interruption. Newer dosing regimens now give loading doses more slowly. One, the Scottish and Newcastle Anti-emetic Pretreatment protocol, using an acetylcysteine regimen of 100 mg/kg over two hours followed by 200 mg/kg over 10 hours, has been widely adopted in the United Kingdom. A cohort comparison study suggests this regimen has comparable efficacy to standard regimens and offers opportunities for selective higher acetylcysteine dosing.

RISK ASSESSMENT AT PRESENTATION

No dose-ranging studies with acetylcysteine were done, and no placebo-controlled studies were performed. Thus, there is uncertainty regarding the optimal dose of acetylcysteine, particularly in patients ingesting very large overdoses of paracetamol. The choice of intervention concentration on the Rumack-Matthew nomogram has important consequences for the proportion of patients treated. The United States National Multicenter Study used a "treatment" line starting at 150 mg/L (992 µmol/L) at 4 hours post overdose, extending to 24 hours with a half-life of 4 hours, now standard there, and subsequently adopted in Australia and New Zealand. In the United Kingdom, the treatment line was initially 200 mg/L (1,323 µmol/L) at 4 hours (the Rumack-Matthew "risk" line). In 2012, the United Kingdom Medicines and Healthcare products Regulatory Agency lowered the treatment line to 100 mg/L (662 µmol/L) at 4 hours for all patients, increasing the number of patients admitted and treated at a high cost. Risk assessment is a key issue for ongoing study, particularly following the development of potential new antidotes that may act in those at greatest risk. The development of biomarkers to assess risk is ongoing but has yet to reach clinical trials.

CONCLUSION

Even after 50 years, there are still areas of uncertainty. These include appropriate acetylcysteine doses in patients who ingest different paracetamol doses or multiple (staggered) ingestions, early identification of at-risk patients, and optimal treatment of late presenters.

Environmental Risk Factors, Protective Factors, and Biomarkers for Allergic Rhinitis: A Systematic Umbrella Review of the Evidence

Many potential environmental risk factors, protective factors, and biomarkers of AR have been published, but so far, the strength and consistency of their evidence are unclear. We conducted a comprehensive review of environmental risk, protective factors, and biomarkers for AR to establish the evidence hierarchy. We systematically searched Embase, PubMed, Cochrane Library, and Web of Science electronic database from inception to December 31, 2022. We calculated summary effect estimate (odds ratio (OR), relative risk (RR), hazard ratio (HR), and standardized mean difference (SMD)), 95% confidence interval, random effects p value, I2 statistic, 95% prediction interval, small study effects, and excess significance biases, and stratification of the level of evidence. Methodological quality was assessed by AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews 2). We retrieved 4478 articles, of which 43 met the inclusion criteria. The 43 eligible articles identified 31 potential environmental risk factors (10,806,206 total population, two study not reported), 11 potential environmental protective factors (823,883 total population), and 34 potential biomarkers (158,716 total population) for meta-analyses. The credibility of evidence was convincing (class I) for tic disorders (OR = 2.89, 95% CI 2.11-3.95); and highly suggestive (class II) for early-life antibiotic use (OR = 3.73, 95% CI 3.06-4.55), exposure to indoor dampness (OR = 1.49, 95% CI 1.27-1.75), acetaminophen exposure (OR = 1.54, 95% CI 1.41-1.69), childhood acid suppressant use (OR = 1.40, 95% CI 1.23-1.59), exposure to indoor mold (OR = 1.66, 95% CI 1.26-2.18), coronavirus disease 2019 (OR = 0.11, 95% CI 0.06-0.22), and prolonged breastfeeding (OR = 0.72, 95% CI 0.65-0.79). This study is registered in PROSPERO (CRD42022384320).

Management of Acetaminophen Poisoning in the US and Canada: A Consensus Statement

Importance

The US and Canada currently have no formal published nationwide guidelines for specialists in poison information or emergency departments for the management of acetaminophen poisoning, resulting in significant variability in management.

Objective

To develop consensus guidelines for the management of acetaminophen poisoning in the US and Canada.

Evidence Review

Four clinical toxicology societies (America's Poison Centers, American Academy of Clinical Toxicology, American College of Medical Toxicology, and Canadian Association of Poison Control Centers) selected participants (n = 21). Led by a nonvoting chairperson using a modified Delphi method, the panel created a decision framework and determined the appropriate clinical management of a patient with acetaminophen poisoning. Unique to this effort was the collection of guidelines from most poison centers in addition to systematic collection and review of the medical literature. Comments from review by external organizations were incorporated before the guideline was finalized. The project began in March 2021 and ended in March 2023.

Findings

The search retrieved 84 guidelines and 278 publications. The panel developed guidelines for emergency department management of single or repeated ingestion of acetaminophen. In addition, the panel addressed extended-release formulation, high-risk ingestion, coingestion of anticholinergics or opioids, age younger than 6 years, pregnancy, weight greater than 100 kg, and intravenous acetaminophen use. Differences from current US practice include defining acute ingestion as an ingestion presentation from 4 to 24 hours after overdose was initiated. A revised form of the Rumack-Matthew nomogram was developed. The term massive ingestion was replaced with the term high-risk ingestion and denoted by a specific nomogram line. Other recommendations include specific criteria for emergency department triage, laboratory evaluation and monitoring parameters, defining the role of gastrointestinal decontamination, detailed management of acetylcysteine treatment, associated adverse effects, and stopping criteria for acetylcysteine treatment, as well as criteria for consultation with a clinical toxicologist. Finally, specific treatment considerations, including acetylcysteine dosing, fomepizole administration, and considerations for extracorporeal elimination and transplant evaluation, were addressed.

Conclusions and Relevance

This qualitative study provides a consensus statement on consistent evidence-based recommendations for medical, pharmacy, and nursing education and practice to optimize care of patients with acetaminophen poisoning.

A systematic review of self-medication practice during the COVID-19 pandemic: implications for pharmacy practice in supporting public health measures

Introduction

Since the COVID-19 pandemic, self-medication had become highly popular due to the risk of virus infection and overwhelming medical resources. Pharmacists are well-positioned to provide public health education and disease prevention. This study aims to provide an overview of the research about self-medication during COVID-19 and the role of pharmacists in ensuring the drug safety related to self-medication.

Methods

Databases (PubMed, Google Scholar, Scopus, EBSCO host, and Web of Science) were searched for published studies on the practice of self-medication in COVID-19 pandemic without restriction in population and location. Primary search terms were "self-medication," "self-care," "self-management," "non-prescription drugs," "2019nCoV," and "COVID-19." Studies conducted during the pandemic but not exclusively for COVID-19 disease were eligible for inclusion.

Results

The database search yielded a total of 4,752 papers. After appropriate screening, 62 articles met the inclusion criteria. Most of the studies were cross-sectional in nature. The review highlighted a very high prevalence of self-medication during COVID-19, ranging from 7.14 to 88.3%. The purpose of self-medication was mainly to treat and prevent COVID-19; fever, body aches, cough, headache, and sore throat were the most frequently mentioned indications. Categories of drugs commonly used in self-medication included antibiotics, herbs, vitamins, and analgesics, most of which came from pharmacies. Information about self-medication usually obtained from relatives and friends, social networks and health care professionals. Common reasons for self-medication included saving money and time, prior experience and mild illness; reasons associated with COVID-19 were mainly fear of contracting the virus and poor access to doctors. Gender, age, education, marital status, and concern about COVID-19 were the most usual associated factors. The role of pharmacists in self-medication included sources of information, advice on medication use, and management of adverse reactions.

Conclusion

During the COVID-19 pandemic, self-medication practices were widespread and varied across countries and populations. Self-medication has emerged as an important component of health care, but also as a huge global challenge. The engagement of healthcare administrators and policy makers are essential to regulate self-medication practices. The expertise and favorable conditions of pharmacists make them positioned as key roles in public health interventions for self-medication.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=395423, identifier CRD42023395423.

Neurologic Complications of Critical Medical Illness

OBJECTIVE

This article reviews the neurologic complications encountered in patients admitted to non-neurologic intensive care units, outlines various scenarios in which a neurologic consultation can add to the diagnosis or management of a critically ill patient, and provides advice on the best diagnostic approach in the evaluation of these patients.

LATEST DEVELOPMENTS

Increasing recognition of neurologic complications and their adverse impact on long-term outcomes has led to increased neurology involvement in non-neurologic intensive care units. The COVID-19 pandemic has highlighted the importance of having a structured clinical approach to neurologic complications of critical illness as well as the critical care management of patients with chronic neurologic disabilities.

ESSENTIAL POINTS

Critical illness is often accompanied by neurologic complications. Neurologists need to be aware of the unique needs of critically ill patients, especially the nuances of the neurologic examination, challenges in diagnostic testing, and neuropharmacologic aspects of commonly used medications.

Deliberate Self-Poisoning: Real-Time Characterization of Suicidal Habits and Toxidromes in the Food and Drug Administration Adverse Event Reporting System

INTRODUCTION

Deliberate self-poisoning (DSP) using drugs is the preferred method of suicide at a global level. Its investigation is hampered by limited sample sizes and data reliability. We investigate the role of the US FDA Adverse Event Reporting System (FAERS), a consolidated pharmacovigilance database, in outlining DSP habits and toxidromes.

METHODS

We retrieved cases of 'intentional overdose' and 'poisoning deliberate' from the FAERS (January 2004-December 2021). Using descriptive and disproportionality analyses, we estimated temporal trends, potential risk factors, toxidromes, case-fatality rates and lethal doses (LDs) for the most frequently reported drugs.

RESULTS

We retrieved 42,103 DSP cases (17% fatal). Most cases were submitted in winter. Reports of DSP involved younger people, psychiatric conditions, and alcohol use, compared with non-DSP, and fatality was higher in men and older patients. Suspected drugs were mainly antidepressants, analgesics, and antipsychotics. Multiple drug intake was recorded in more than 50% of the reports, especially analgesics, psychotropics, and cardiovascular agents. The most frequently reported drugs were paracetamol, promethazine, amlodipine, quetiapine, and metformin. We estimated LD25 for paracetamol (150 g).

CONCLUSION

Worldwide coverage of the FAERS complements existing knowledge about DSP and may drive tailored prevention measures to timely address the DSP phenomenon and prevent intentional suicides.

Non-Intentional N-Acetylcysteine Overdose Associated with Cerebral Edema and Brain Death

N-acetylcysteine is the established treatment for acetaminophen toxicity. This medication's complex dosing schedule engenders a high incidence of medication errors. While nuisance side effects are common, only rare case reports describe serious outcomes associated with N-acetylcysteine administration, all of which take place in the setting of non-intentional N-acetylcysteine overdose. This case report contributes to a small but growing literature that suggests that large N-acetylcysteine overdose may have devastating outcomes. We describe a 15-year-old female who presented with stage III acetaminophen toxicity and who received a non-intentional 6-fold overdose of intravenous N-acetylcysteine due to a medication prescribing error. During the N-acetylcysteine infusion dosing error, the patient had clinical deterioration including seizure followed by cerebral edema and brain herniation that progressed to brain death. She developed agitation and worsening headache within 2 h of the dosing error, which progressed to seizure and intubation 14 h into the dosing error. Although possibly due to hepatic encephalopathy, at the time she developed fixed dilated pupils, her lactate, international normalized ratio, aspartate aminotransferase, and alanine aminotransferase had all improved. On review of the literature, other case reports of seizures (n = 4) and cerebral edema with brain herniation (n = 3) were found, suggesting our patient was not an isolated case. Clinicians need to be aware of the common occurrence of dosing errors for N-acetylcysteine infusions. We suggest institutions review their N-acetylcysteine ordering, dosing, and mixing protocols in order to avoid similar rare errors in the future. Iatrogenic overdose of N-acetylcysteine can cause seizure, cerebral edema, and brain death.

The Role of Activated Charcoal in Prehospital Care

Background

Administration of a single-dose activated charcoal (SDAC) is an effective method used for gastric decontamination and for other types of poisoning and overdose. This is only true when given within the first hour of poison ingestion as the effectivity of SDAC reduces over time. In addition, generally, not all patients are able to avail treatment within the specified period. Hence, multi-dose activated charcoal is regarded as a solution to a delayed process, although, no proof outweighs the use of SDAC.

Objective

This study aimed to review and assess the adequacy of the past and current use of AC. The author also aimed to offer recommendations believed to be the best method to consider for prehospital care.

Methods

The author conducted 6,337 online literature searches for this review, wherein seven papers met eligibility criteria for inclusion and analysis.

Results

In this review, routine administration of AC in poisoning was found not related to the duration of hospital stay nor any other subsequent outcomes following poison ingestion. Further, this review did not establish that administration of AC could improve patient's clinical outcome. Further research and clinical trials is required to determine the efficacy of this therapy to appropriate patients in the prehospital setting.

Conclusion

Activated charcoal can be used to treat highly acute to life-threatening poisoning if it is administered within the first hour of ingestion. Further studies would be necessary to investigate if this would affect clinical outcome..

A 36-Year-Old Woman with Acute Liver Failure Following Acetaminophen Overdose, Raised INR of 8.7, and Normal Blood Viscosity Measured by Rotational Thromboelastometry (ROTEM)

BACKGROUND Fulminant hepatic failure (FHF) is commonly associated with elevated prothrombin time (PT) and international normalized ratio (INR). There is a commensurate decline in pro- and anti-hemostatic factors, and hemostatic function is rebalanced, not reflected in INR. This report presents the case of a 36-year-old woman with FHF following acetaminophen overdose, an increased INR above 8.7, and normal blood viscosity measured by rotational thromboelastometry (ROTEM). CASE REPORT A 36-year-old woman presented with FHF following an acetaminophen overdose. On arrival, she was lethargic but arousable and followed commands. Her King's College Criteria for acetaminophen toxicity was 2 and her MELD score was 36. Her INR was unmeasurably high (>8.7). To evaluate whole-blood coagulation, a ROTEM analysis was performed. All parameters (CT, CFT, alpha-angle, A10, MCF) of the NATEM were within reference range. Despite the normal ROTEM, spontaneous bleeding was a concern. The patient received 5 units of cryoprecipitate and 9 units of FFP prior to a central venous line placement. She was started on molecular adsorbent recirculating system and continuous veno-venous hemodialysis, but died on day 7. CONCLUSIONS Patients with FHF can have normal whole-blood coagulation based on ROTEM even if INR levels are unmeasurably high. Viscoelastic tests such as ROTEM, which assesses whole-blood coagulation properties, are preferrable for coagulation monitoring in these patients. Blood product transfusion to correct coagulation abnormality, like FFP and cryoprecipitate, may be used based on the result of viscoelastic testing over conventional coagulation testing.

Paracetamol (acetaminophen) overdose and hepatotoxicity: mechanism, treatment, prevention measures, and estimates of burden of disease

INTRODUCTION

Paracetamol is one of the most used medicines worldwide and is the most common important poisoning in high-income countries. In overdose, paracetamol causes dose-dependent hepatotoxicity. Acetylcysteine is an effective antidote, however despite its use hepatotoxicity and many deaths still occur.

AREAS COVERED

This review summarizes paracetamol overdose and toxicity (including mechanisms, risk factors, risk assessment, and treatment). In addition, we summarize the epidemiology of paracetamol overdose worldwide. A literature search on PubMed for poisoning epidemiology and mortality from 1 January 2017 to 26 October 2022 was performed to estimate rates of paracetamol overdose, liver injury, and deaths worldwide.

EXPERT OPINION

Paracetamol is widely available and yet is substantially more toxic than other analgesics available without prescription. Where data were available, we estimate that paracetamol is involved in 6% of poisonings, 56% of severe acute liver injury and acute liver failure, and 7% of drug-induced liver injury. These estimates are limited by lack of available data from many countries, particularly in Asia, South America, and Africa. Harm reduction from paracetamol is possible through better identification of high-risk overdoses, and better treatment regimens. Large overdoses and those involving modified-release paracetamol are high-risk and can be targeted through legislative change.

Successful management of delayed presentation of massive paracetamol overdose in a resource-limited setting: A case report from Nepal

We present a case of self-poisoning with a massive dose of paracetamol by a young Nepalese female patient who presented late to our emergency department. This report highlights the successful management of the patient with the extended use of N-acetylcysteine over 4 days and continuous supportive therapy as required. The case is an example of the management of delayed presentation of a massive paracetamol poisoning in a resource-limited setting, where intensive care units and hemodialysis facilities are not easily available. However, when available, massive poisoning should always be managed in continuous monitoring units under the expertise of a toxicologist.

Acetaminophen toxicity and overdose: current understanding and future directions for NAC dosing regimens

INTRODUCTION

Although N-acetyl-cysteine (NAC) has long been used for the treatment of acetaminophen poisoning/overdose, the optimal NAC dosing regimen for varying patterns or severity of the poisoning/overdose is still unknown.

AREAS COVERED

Relevant literature was searched for in the MEDLINE (from 1964 until August 31^st, 2022), SCOPUS (from 2004 until August 31^st, 2022) and GOOGLE SCHOLAR (from 2004 until August 31^st, 2022) databases, without restriction in terms of publication date. The inclusion criteria were: original clinical studies reporting results, and studies investigating efficacy and safety of NAC dosing regimens in case(s) of overdose or poisoning with acetaminophen.

EXPERT OPINION

For a more effective treatment of acetaminophen poisoning in the future, it will be crucial to advance the technology of measuring acetaminophen, its metabolites and NAC in the serum, preferably with the point-of-care technique, so that in real time it can be continuously assessed whether it is necessary to administer NAC, and further to increase the dose of NAC and extend the duration of its administration, or not.

The role of platelet mediated thromboinflammation in acute liver injury

Acute liver injuries have wide and varied etiologies and they occur both in patients with and without pre-existent chronic liver disease. Whilst the pathophysiological mechanisms remain distinct, both acute and acute-on-chronic liver injury is typified by deranged serum transaminase levels and if severe or persistent can result in liver failure manifest by a combination of jaundice, coagulopathy and encephalopathy. It is well established that platelets exhibit diverse functions as immune cells and are active participants in inflammation through processes including immunothrombosis or thromboinflammation. Growing evidence suggests platelets play a dualistic role in liver inflammation, shaping the immune response through direct interactions and release of soluble mediators modulating function of liver sinusoidal endothelial cells, stromal cells as well as migrating and tissue-resident leucocytes. Elucidating the pathways involved in initiation, propagation and resolution of the immune response are of interest to identify therapeutic targets. In this review the provocative role of platelets is outlined, highlighting beneficial and detrimental effects in a spatial, temporal and disease-specific manner.

Preventive Effects of Mandarin Fruit Peel Hydroethanolic Extract, Hesperidin, and Quercetin on Acetaminophen-Induced Hepatonephrotoxicity in Wistar Rats

Acetaminophen, also known as N-acetyl-para-aminophenol (NAPAP), is a traditional antipyretic and analgesic that is used extensively around the world to treat colds and fevers. However, a NAPAP excess causes rapid, severe liver and kidney damage. The goal of the study was to examine the protective effects and determine the mechanisms of action of MPHE, hesperidin, and quercetin in NAPAP-induced hepatorenal damage in Wistar rats. Male Wistar rats received a 0.5 g/kg oral supplement of NAPAP every other day for a period of four weeks. During the same period of NAPAP supplementation, MPHE (50 mg/kg), quercetin (20 mg/kg), and hesperidin (20 mg/kg) were administered to rats receiving NAPAP. MPHE, quercetin, and hesperidin treatments significantly improved liver function in NAPAP-supplemented rats. The high serum levels of aminotransferases, alkaline phosphatase, lactate dehydrogenase, and γ-glutamyl transferase as well as total bilirubin were significantly reduced, while the levels of suppressed serum albumin were significantly increased, demonstrating this improvement. Treatments utilizing these natural substances significantly enhanced kidney function as seen by a considerable decline in the increased blood levels of urea, uric acid, and creatinine. Additionally, the injection of MPHE, hesperidin, and quercetin resulted in a decrease in the quantity of lipid peroxides while increasing the activities of superoxide dismutase, glutathione peroxidase, and glutathione-S-transferase in the liver and kidneys. The treatments markedly abated the NAPAP-induced liver and kidney histological perturbations and reduced the NAPAP-induced serum tumor necrosis factor-α level and liver and kidney proapoptotic protein 53 and caspase 3 expressions. Otherwise, serum interleukin-4 level significantly increased by treatments. The MPHE, hesperidin, and quercetin treatments resulted in marked decrease in liver and kidney histopathological scores including inflammation, necrosis, apoptosis, and congestion. In conclusion, the MPHE, quercetin, and hesperidin may induce hepatonephropreventive impacts in NAPAP-supplemented rats via enhancing the antioxidant defense system, anti-inflammatory activity, and antiapoptotic action.

N-Acetylcysteine for Preventing Acetaminophen-Induced Liver Injury: A Comprehensive Review

Aims: N-Acetylcysteine (NAC) is used as an antidote in acetaminophen (APAP) overdose to prevent and mitigate drug-induced liver injury (DILI). Our objective was to systematically review evidence of the use of NAC as a therapeutic option for APAP overdose and APAP-related DILI in order to define the optimal treatment schedule and timing to start treatment. Methods: Bibliographic databases (PubMed, Web of Science, Embase, and MEDLINE) were searched for retrospective and prospective cohort studies, case series, and clinical trials. The prespecified primary outcomes were DILI-related mortality, hepatotoxicity, and adverse events (AEs). Results: In total, 34 studies of NAC usage in APAP-related DILI cases with 19,580 patients were identified, of which 2,376 patients developed hepatotoxicities. The mortality rate across different studies ranged from 0 to 52%. Large variability of NAC regimens was found, i.e., intravenous (I.V.) (100-150 mg/kg) and oral (70-140 mg/kg), and length of treatment varied-12, 24, or 48 h for I.V. regimen and 72 h for oral administration. The timing of initiation of NAC treatment showed different results in terms of occurrence of hepatotoxicity and mortality; if started within 8 h and no more than 24 h from APAP overdose, either intravenously or orally, NAC administration was efficacious in terms of mortality. The most frequent AEs reported were anaphylactic reactions, followed by cutaneous AEs for the IV route and intestinal AEs for the oral one. Conclusion: NAC improves hepatotoxicity and reduces mortality. Timing of treatment, ranging from 8 to 24 h from APAP overdose, regardless of the regimen or route of administration, is important to prevent or minimize liver damage, particularly in children and in elderly and obese patients.

N-Acetylcysteine for the Management of Non-Acetaminophen Drug-Induced Liver Injury in Adults: A Systematic Review

Introduction: Idiosyncratic drug-induced liver injury (DILI) is a rare adverse reaction to drugs and other xenobiotics. DILI has different grades of severity and may lead to acute liver failure (ALF), for which there is no effective therapy. N-acetylcysteine (NAC) has been occasionally tested for the treatment of non-acetaminophen drug-induced ALF. However, limited evidence for its efficacy and safety is currently available. Our aim was to elucidate the benefit and safety of NAC in DILI and evaluate its hepatoprotective effect. Methods: We conducted a systematic review to evaluate the management and prevention focused on NAC in idiosyncratic DILI. The main outcomes included mortality due to DILI, time to normalization of liver biochemistry, transplant-free survival, and adverse events. We included clinical trials and observational studies, either prospective or retrospective. Results: A total of 11 studies were included after literature screening. All studies had different methodologies, and some of them had important risk of bias that may lead to interpreting their findings with caution. The majority of the studies proved NAC efficacy in a cohort of patients with ALF due to different etiologies, where DILI represented a subgroup. NAC seemed to improve transplant-free survival; however, its benefit was inconclusive in terms of overall survival. With regard to safety, NAC showed an adequate safety profile. In prevention studies, NAC showed a possible hepatoprotective effect; however, this finding is limited by the lack of studies and presence of bias. Conclusion: NAC treatment seems to have some benefit in non-acetaminophen drug-induced liver failure patients with acceptable safety; however, due to the lack of evidence and limitations detected across studies, its benefit must be corroborated in clinical trials with adequate methodology.

Delayed Acetaminophen Absorption Resulting in Acute Liver Failure

Introduction. Acetaminophen is a common medication involved in deliberate and accidental self-poisoning. The acetaminophen treatment nomogram is used to guide acetylcysteine treatment. It is rare to develop hepatotoxicity with an initial acetaminophen concentration below the nomogram line. We present a case of acetaminophen ingestion with an initial concentration below the nomogram line that developed hepatic failure, due to a delayed peak acetaminophen concentration secondary to coingesting medications that slow gastric emptying. Case Report. A 43-year-old (55 kg) female presented after ingesting an unknown quantity of acetaminophen, clonidine, and alcohol. Her acetaminophen level was 41 mg/L (256 μmol/L) at 4.5 h post-ingestion, well below the nomogram line, and ALT was 25 U/L. Hence, acetylcysteine was not commenced. She was intubated for decreased level of conscious. A repeat acetaminophen level 4 h later was 39 mg/L (242 μmol/L), still below the nomogram line. She was extubated 24 h later.At 38 h post-ingestion she developed abdominal pain, the repeat acetaminophen level was 85 mg/L (560 μmol/L), ALT was 489 U/L, and acetylcysteine was commenced. The patient developed hepatic failure with a peak ALT of 7009 U/L and INR of 7.5 but made a full recovery. It was discovered that she had ingested a combination acetaminophen product containing dextromethorphan and chlorphenamine. Acetaminophen metabolites were measured, including nontoxic glucuronide and sulfate conjugates and toxic cytochrome P450 (CYP) metabolites. The metabolite data demonstrated increasing CYP metabolites in occurrence with the delayed acetaminophen peak concentration. Discussion. Opioids and antimuscarinic agents are known to delay gastric emptying and clonidine may also have contributed. These coingested medications resulted in delayed acetaminophen absorption. This case highlights the issue of altered pharmacokinetics when patients coingest gut slowing agents.

Molecular pathogenesis of acetaminophen-induced liver injury and its treatment options

Acetaminophen, also known as N-acetyl-p-aminophenol (APAP), is commonly used as an antipyretic and analgesic agent. APAP overdose can induce hepatic toxicity, known as acetaminophen-induced liver injury (AILI). However, therapeutic doses of APAP can also induce AILI in patients with excessive alcohol intake or who are fasting. Hence, there is a need to understand the potential pathological mechanisms underlying AILI. In this review, we summarize three main mechanisms involved in the pathogenesis of AILI: hepatocyte necrosis, sterile inflammation, and hepatocyte regeneration. The relevant factors are elucidated and discussed. For instance, N-acetyl-p-benzoquinone imine (NAPQI) protein adducts trigger mitochondrial oxidative/nitrosative stress during hepatocyte necrosis, danger-associated molecular patterns (DAMPs) are released to elicit sterile inflammation, and certain growth factors contribute to liver regeneration. Finally, we describe the current potential treatment options for AILI patients and promising novel strategies available to researchers and pharmacists. This review provides a clearer understanding of AILI-related mechanisms to guide drug screening and selection for the clinical treatment of AILI patients in the future.

Mesenchymal stem cells protect against acetaminophen hepatotoxicity by secreting regenerative cytokine hepatocyte growth factor

BACKGROUND

Acetaminophen (APAP) overdose is a major cause of the morbidity of acute liver failure. The current clinically approved treatment for APAP poisoning, N-acetylcysteine (NAC), has a limited therapeutic window, and prolonged treatment with NAC delays liver regeneration. Mesenchymal stem cells (MSCs) also have therapeutic effects on APAP-induced mouse liver failure, but whether the effects are comparable to those of NAC has not been determined, and the mechanism still needs further exploration.

METHODS

Fasted C57BL/6 mice that received 500 mg/kg APAP were treated intravenously with 300 mg/kg NAC or different amounts of MSCs at 2 h after APAP to investigate survival, hepatocyte necrosis and neutrophil/macrophage recruitment. In vitro co-culture was performed to study the anti-necrotic effects of MSCs on the APAP-injured hepatocyte cell line L-O2.

RESULTS

MSCs dose-dependently rescued the C57BL/6J mice from APAP-induced liver failure, with 87.5% of MSCs (1 × 10⁶) surviving similar to that of NAC (90%). MSC has similar effects on reduced hepatocyte necrosis and granulocytic myeloid-derived suppressor cells (MDSC) infiltration but enhanced the proportion of regenerative monocytic MDSC when compared to NAC. Mechanistically, MSCs attenuate hepatocyte necrosis by secreting hepatocyte growth factor (HGF). When HGF was knocked down, the protective effects of MSCs were reduced on APAP-induced hepatocyte necrosis and mouse liver failure.

CONCLUSIONS

MSCs are comparable to NAC against APAP-induced liver failure by secreting HGF with less regenerative retardation concerns, thus facilitating the application of MSCs in clinical therapy for APAP liver failure.

Has the time come to stop routine N-acetylcysteine treatment in young children in Denmark? A review of 300 suspected paracetamol overdoses in children aged 0-6 years

AIM

To evaluate the prevalence of potentially hepatoxic paracetamol ingestion and associated N-acetylcysteine treatment in young children suspected of paracetamol poisoning.

METHODS

A retrospective cohort study of children aged 0-6 years suspected of paracetamol poisoning with a related plasma-paracetamol measurement in the Capital Region of Denmark in the period 2010-2017. Data from the clinical laboratory system were linked to data from electronic patient records via the unique identification number given to all Danish residents.

RESULTS

Of 297 children included, suspected single paracetamol overdoses were present in 281 (95%). Sixty-nine per cent were treated with N-acetylcysteine, and the mean treatment period was 20.3 h (SD 20.8). A maximum of 6 (2%) of the children suspected of single overdose had plasma-paracetamol concentrations that exceeded the recommended treatment thresholds. No cases of severe hepatotoxicity were registered. Adverse events to N-acetylcysteine-treatment were registered in 3 (2%) children including one anaphylactoid reaction (0.5%).

CONCLUSION

This study shows that initiating N-acetylcysteine as a 'one size fit all' treatment regimen in all children aged 0-6 years with a suspected single paracetamol overdose leads to substantial overtreatment. The data support that it is feasible to initiate N-acetylcysteine within 10 h based on an early plasma-paracetamol test.

Novel Therapies for the Treatment of Drug-Induced Liver Injury: A Systematic Review

Many drugs with different mechanisms of action and indications available on the market today are capable of inducing hepatotoxicity. Drug-induced liver injury (DILI) has been a treatment challenge nowadays as it was in the past. We searched Medline (via PubMed), CENTRAL, Science Citation Index Expanded, clinical trials registries and databases of DILI and hepatotoxicity up to 2021 for novel therapies for the management of adult patients with DILI based on the combination of three main search terms: 1) treatment, 2) novel, and 3) drug-induced liver injury. The mechanism of action of novel therapies, the potential of their benefit in clinical settings, and adverse drug reactions related to novel therapies were extracted. Cochrane Risk of bias tool and Grading of Recommendations Assessment, Development and Evaluation (GRADE) assessment approach was involved in the assessment of the certainty of the evidence for primary outcomes of included studies. One thousand three hundred seventy-two articles were identified. Twenty-eight articles were included in the final analysis. Eight randomized controlled trials (RCTs) were detected and for six the available data were sufficient for analysis. In abstract form only we found six studies which were also anaylzed. Investigated agents included: bicyclol, calmangafodipir, cytisin amidophospate, fomepizole, livina-polyherbal preparation, magnesium isoglycyrrhizinate (MgIG), picroliv, plasma exchange, radix Paeoniae Rubra, and S-adenosylmethionine. The primary outcomes of included trials mainly included laboratory markers improvement. Based on the moderate-certainty evidence, more patients treated with MgIG experienced alanine aminotransferase (ALT) normalization compared to placebo. Low-certainty evidence suggests that bicyclol treatment leads to a reduction of ALT levels compared to phosphatidylcholine. For the remaining eight interventions, the certainty of the evidence for primary outcomes was assessed as very low and we are very uncertain in any estimate of effect. More effort should be involved to investigate the novel treatment of DILI. Well-designed RCTs with appropriate sample sizes, comparable groups and precise, not only surrogate outcomes are urgently welcome.

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.

What is a Therapeutic Potential of N-Acetylcysteine in Lung Silicosis?

Lung silicosis is a serious pulmonary disease caused by an exposure of lung to inhaled silicon dioxide (SiO2) or silica. Although pathomechanisms of the disease have not been fully elucidated, oxidative stress has been recognized as a fundamental factor triggering a fibrotizing inflammation leading to irreversible changes in lung tissue. Based on this knowledge, therapeutic potential of various antioxidants has been intensively discussed. Among them, N-acetylcysteine with its multiple anti-inflammatory and antioxidant actions and a long-term experience with its clinical use in various diseases appears as a very promising choice. The purpose of this article is to review the therapeutic effects of N-acetylcysteine particularly in relation to a lung injury and to point out a potential of N-acetylcysteine in the treatment of lung silicosis.

Pregnancy after liver transplant: maternal and perinatal outcomes

BACKGROUND

Liver transplantation is a life-saving and successful therapeutic procedure which is more and more frequent worldwide, also among women of reproductive age. Consequently, there is an increasing number of reports of pregnancy following liver transplantation, but doubts still exist regarding preconception counseling and the optimal method of managing pregnancy. The aim of this study was to report and evaluate pregnancy outcomes in women who had undergone liver transplantation.

METHODS

We retrospectively analyzed female patients after orthotopic liver transplantation who reported pregnancy and were under medical care of a single transplant center.

RESULTS

We identified 14 pregnancies in 10 women who had undergone liver transplantation (12 childbirths, one induced abortion due to fetal death in the first trimester, one pregnancy is still ongoing). Causes of transplantation include congenital or acquired disorders and the most common indication was autoimmune hepatitis (50%). The mean age at the point of transplantation was 28.5 (range 21-36), mean maternal age at pregnancy was 32 (range 26-43), and transplant-to-pregnancy interval was 4.07 years (range 1.5-7). The mean gestational week was 36.67 (range 31-40). Immunosuppression was maintained with combinations of prednisone (n = 11), tacrolimus (n = 13), and azathioprine (n = 8) prior to and during pregnancy. Two pregnancies were unintended, so women took mycophenolate mofetil in the first weeks of gestation. Another two women stopped taking azathioprine due to increasing anemia. Maternal complications included increase of aspartate transaminase and alanine transaminase (n = 2), anemia (n = 4) and hyperthyroidism (n = 2). Among the 12 childbirths, five (41.67%) were preterm. Only five women entered labor spontaneously, while seven (58,33%) had cesarean delivery.

CONCLUSIONS

Pregnancy after liver transplantation can achieve relatively favorable outcomes. Liver transplantation does not influence women's fertility and, during pregnancy, we report low rates of minor graft complications. A multidisciplinary team should be involved in contraceptive, fertility and consequently pregnancy counseling of female transplant recipients.

Risk Factors for Hepatotoxicity Due to Paracetamol Overdose in Adults

Background and Objectives: Over-the-counter availability and a good safety profile make paracetamol one of the most common analgesics in developed countries but also the leading cause of liver failure due to overdose. The objectives of the study were to identify modifiable risk factors for severe hepatotoxicity following paracetamol overdose in adults. Materials and Methods: A retrospective cohort study involved the consecutive adult patients hospitalized in a toxicological center over a period of seven years due to paracetamol overdose. Complete medical datasets of laboratory and anamnestic variables were analyzed and validated by means of logistic regression model. Results: A total of 185 patients entered the study, including 25 individuals who developed severe hepatotoxicity (plasma aminotransferases levels above 1000 UI/L) and 31 individuals with mild to moderate liver injury (plasma aminotransferases levels above upper normal range, but below 1000 UI/L). In the univariable analysis, significant hepatotoxicity risk factors were male gender, alcohol abuse, an ingested paracetamol dose, and a timespan from ingestion to hospital admission. The later one was the only significant risk factor in the multivariable model (adjusted odds ratio 1.08; 95% CI: 1.03-1.12). Conclusions: A delay in hospital admission, resulting in a delayed administration of disease-specific treatment outweighs any other known risk factors of paracetamol-induced hepatotoxicity.

Massive Acetaminophen Overdose Treated Successfully with N-Acetylcysteine, Fomepizole, and Hemodialysis

Acetaminophen overdose is one of the most common causes of acute hepatic failure in the developed world. There is strong evidence for N-acetylcysteine (NAC) as a safe and effective antidote for acetaminophen toxicity. However, there is less clarity in the management of massive overdoses (acute, single ingestions > 500 mg/kg with 4-hour equivalent concentrations ~6000 μmol/L) which are often associated with metabolic acidosis and multiorgan dysfunction. In such ingestions, the role of adjuvant treatments such as fomepizole and extracorporeal removal is unclear. We present a case of a 20-year-old female presenting with an acute ingestion of over 120 grams (1764.7 mg/kg) and an acetaminophen concentration of 5880 μmol/L who developed refractory shock, decreased level of consciousness, and metabolic acidosis requiring mechanical ventilation and vasopressor support. She was treated with gastric decontamination with activated charcoal, IV NAC, fomepizole, and hemodialysis. The patient had complete clearance of acetaminophen by 32 hours after presentation and normalization of her acid base and hemodynamic status without any organ failure. This case highlights the potential benefit of a triple strategy of NAC, fomepizole, and early hemodialysis in massive acetaminophen overdose, potentially sparing complications of prolonged intubation and ICU hospitalization.

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.

[Once upon a time the hepatotoxicity…]

The liver ensures a large part of xenobiotics metabolism thanks to its sizeable enzymatic equipment, its anatomical localization and its abundant vascularization. However, these various characteristics also make it a privileged target for toxic compounds, particularly in the case of a toxic metabolism. Xenobiotics-induced hepatotoxicity is a major cause of liver damage and a real challenge for clinicians, pharmaceutical industry, and health agencies. Intrinsic, i.e. predictable and reproducible hepatotoxicities occurring at threshold doses are distinguished from idiosyncratic hepatotoxicities, occurring in an unpredictable manner in people with individual susceptibilities. Among them, idiosyncratic immune-mediated hepatotoxicity pathophysiology is still unclear. However, the development of tools to improve the prediction and understanding of these disorders may open avenues to the identification of risk factors and new mechanisms of toxicity.

A Stepwise Approach for Preventing Suicide by Lethal Poisoning

Background

Suicide is a global phenomenon and is the 10th leading cause of death in the US. Veterans are more likely to die by suicide than those in the general population. In 2018, the suicide rate for all US veterans was 1.5 times higher than the rate for nonveterans, after adjusting for population differences in age and sex. In light of this disparity, suicide prevention is one of the highest priorities for the US Department of Veterans Affairs (VA). One major goal of the VA suicide prevention strategy is to reduce access to lethal means.

Observations

This article will provide information on medications with high lethality and a stepwise approach for how health care providers may limit lethal medications for patients at high risk for suicide. The first step is to determine suicide risk. More than 90% of those who die by suicide have a psychiatric diagnosis at the time of death. Clinicians can use risk assessment tools, such as the Veterans Health Administration Suicide Prevention Population Risk Identification and Tracking for Exigencies tool. The second step is to identify substances strongly associated with fatalities. According to the American Association of Poison Control Centers, the pharmaceutical classes associated with the largest number of fatalities are stimulants and street drugs, followed by analgesics, cardiovascular agents, antidepressants, antipsychotics, and sedatives/hypnotics. The third step is to consider potential drug-drug interactions, such as the combination of opioids and sedative-hypnotics. Finally, clinicians need to address risks. With high-risk patients it may be preferential to prescribe medications that are less lethal. All patients with a high risk of suicide should receive lethal means counseling.

Conclusions

While firearms continue to be the most lethal means for veteran suicide, intentional poisoning with medications or substances also is a common method for suicide, especially for female veterans. Having knowledge of medications with high lethality and limiting access to these agents can be a successful strategy for reducing suicide deaths.

N-acetylcysteine for non-paracetamol (acetaminophen)-related acute liver failure

BACKGROUND

Acute liver failure is a rare and serious disease. Acute liver failure may be paracetamol-induced or non-paracetamol-induced. Acute liver failure not caused by paracetamol (acetaminophen) has a poor prognosis with limited treatment options. N-acetylcysteine has been successful in treating paracetamol-induced acute liver failure and reduces the risk of needing to undergo liver transplantation. Recent randomised clinical trials have explored whether the benefit can be extrapolated to treat non-paracetamol-related acute liver failure. The American Association for the Study of Liver Diseases (AASLD) 2011 guideline suggested that N-acetylcysteine could improve spontaneous survival when given during early encephalopathy stages for patients with non-paracetamol-related acute liver failure.

OBJECTIVES

To assess the benefits and harms of N-acetylcysteine compared with placebo or no N-acetylcysteine, as an adjunct to usual care, in people with non-paracetamol-related acute liver failure.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register (searched 25 June 2020), Cochrane Central Register of Controlled Trials (CENTRAL; 2020, Issue 6) in The Cochrane Library, MEDLINE Ovid (1946 to 25 June 2020), Embase Ovid (1974 to 25 June 2020), Latin American and Caribbean Health Science Information database (LILACS) (1982 to 25 June 2020), Science Citation Index Expanded (1900 to 25 June 2020), and Conference Proceedings Citation Index - Science (1990 to 25 June 2020).

SELECTION CRITERIA

We included randomised clinical trials that compared N-acetylcysteine at any dose or route with placebo or no intervention in participants with non-paracetamol-induced acute liver failure.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as described in the Cochrane Handbook for Systematic Reviews of Interventions. We conducted meta-analyses and presented results using risk ratios (RR) with 95% confidence intervals (CIs). We quantified statistical heterogeneity by calculating I². We assessed bias using the Cochrane risk of bias tool and determined the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included two randomised clinical trials: one with 183 adults and one with 174 children (birth through age 17 years). We classified both trials at overall high risk of bias. One unregistered study in adults is awaiting classification while we are awaiting responses from study authors for details on trial methodology (e.g. randomisation processes). We did not meta-analyse all-cause mortality because of significant clinical heterogeneity in the two trials. For all-cause mortality at 21 days between adults receiving N-acetylcysteine versus placebo, there was inconclusive evidence of effect (N-acetylcysteine 24/81 (29.6%) versus placebo 31/92 (33.7%); RR 0.88, 95% CI 0.57 to 1.37; low certainty evidence). The certainty of the evidence was low due to risk of bias and imprecision. Similarly, for all-cause mortality at one year between children receiving N-acetylcysteine versus placebo, there was inconclusive evidence of effect (25/92 (27.2%) versus 17/92 (18.5%); RR 1.47, 95% CI 0.85 to 2.53; low certainty evidence). We downgraded the certainty of evidence due to very serious imprecision.  We did not meta-analyse serious adverse events and liver transplantation at one year due to incomplete reporting and clinical heterogeneity. For liver transplantation at 21 days in the trial with adults, there was inconclusive evidence of effect (RR 0.72, 95% CI 0.49 to 1.06; low certainty evidence). We downgraded the certainty of the evidence due to serious risk of bias and imprecision. For liver transplantation at one year in the trial with children, there was inconclusive evidence of effect (RR 1.23, 95% CI 0.84 to 1.81; low certainty of evidence). We downgraded the certainty of the evidence due to very serious imprecision.   There was inconclusive evidence of effect on serious adverse events in the trial with children (RR 1.25, 95% CI 0.35 to 4.51; low certainty evidence). We downgraded the certainty of the evidence due to very serious imprecision.  We did not meta-analyse non-serious adverse events due to clinical heterogeneity. There was inconclusive evidence of effect on non-serious adverse events in adults (RR 1.07, 95% CI 0.79 to 1.45; 173 participants; low certainty of evidence) and children (RR 1.19, 95% CI 0.62 to 2.16; 184 participants; low certainty of evidence). None of the trials reported outcomes of proportion of participants with resolution of encephalopathy and coagulopathy or health-related quality of life. The National Institute of Health in the United States funded both trials through grants. One of the trials received additional funding from two hospital foundations' grants. Pharmaceutical companies provided the study drug and matching placebo, but they did not have input into study design nor involvement in analysis.

AUTHORS' CONCLUSIONS

The available evidence is inconclusive regarding the effect of N-acetylcysteine compared with placebo or no N-acetylcysteine, as an adjunct to usual care, on mortality or transplant rate in non-paracetamol-induced acute liver failure. Current evidence does not support the guideline suggestion to use N-acetylcysteine in adults with non-paracetamol-related acute liver failure, nor the rising use observed in clinical practice. The uncertainty based on current scanty evidence warrants additional randomised clinical trials with non-paracetamol-related acute liver failure evaluating N-acetylcysteine versus placebo, as well as investigations to identify predictors of response and the optimal N-acetylcysteine dose and duration.

Management of pharmaceutical and recreational drug poisoning

BACKGROUND

Poisoning is one of the leading causes of admission to the emergency department and intensive care unit. A large number of epidemiological changes have occurred over the last years such as the exponential growth of new synthetic psychoactive substances. Major progress has also been made in analytical screening and assays, enabling the clinicians to rapidly obtain a definite diagnosis.

METHODS

A committee composed of 30 experts from five scientific societies, the Société de Réanimation de Langue Française (SRLF), the Société Française de Médecine d'Urgence (SFMU), the Société de Toxicologie Clinique (STC), the Société Française de Toxicologie Analytique (SFTA) and the Groupe Francophone de Réanimation et d'Urgences Pédiatriques (GFRUP) evaluated eight fields: (1) severity assessment and initial triage; (2) diagnostic approach and role of toxicological analyses; (3) supportive care; (4) decontamination; (5) elimination enhancement; (6) place of antidotes; (7) specificities related to recreational drug poisoning; and (8) characteristics of cardiotoxicant poisoning. Population, Intervention, Comparison, and Outcome (PICO) questions were reviewed and updated as needed, and evidence profiles were generated. Analysis of the literature and formulation of recommendations were then conducted according to the GRADE® methodology.

RESULTS

The SRLF-SFMU guideline panel provided 41 statements concerning the management of pharmaceutical and recreational drug poisoning. Ethanol and chemical poisoning were excluded from the scope of these recommendations. After two rounds of discussion and various amendments, a strong consensus was reached for all recommendations. Six of these recommendations had a high level of evidence (GRADE 1±) and six had a low level of evidence (GRADE 2±). Twenty-nine recommendations were in the form of expert opinion recommendations due to the low evidences in the literature.

CONCLUSIONS

The experts reached a substantial consensus for several strong recommendations for optimal management of pharmaceutical and recreational drug poisoning, mainly regarding the conditions and effectiveness of naloxone and N-acetylcystein as antidotes to treat opioid and acetaminophen poisoning, respectively.

Massive Acetaminophen Overdose

The authors present a case of a fatal intentional acetaminophen (APAP) overdose and remind the physician how ubiquitous the drug is. This case presentation highlights the clinical presentation and treatment options for APAP overdose in unresponsive patients. In cases of massive APAP overdose (> 300 µg/ml plasma at four hours post-ingestion), prompt administration of N-acetylcysteine (NAC) and early hemodialysis are indicated.

Liver injury induced by paracetamol and challenges associated with intentional and unintentional use

Drug induced liver injury (DILI) is a common cause of acute liver injury. Paracetamol, also known as acetaminophen, is a widely used anti-pyretic that has long been established to cause liver toxicity once above therapeutic levels. Hepatotoxicity from paracetamol overdose, whether intentional or non-intentional, is the most common cause of DILI in the United States and remains a global issue. Given the increased prevalence of combination medications in the form of pain relievers and antihistamines, paracetamol can be difficult to identify and remains a significant cause of acute hepatotoxicity, as evidenced by its contribution to over half of all acute liver failure cases in the United States. This is especially concerning given that, when co-ingested with other medications, the rise in serum paracetamol levels may be delayed past the 4-hour post-ingestion mark that is currently used to determine patients that require medical therapy. This review serves to describe the clinical and pathophysiologic features of hepatotoxicity secondary to paracetamol and provide an update on current available knowledge and treatment options.

Medicinal Thiols: Current Status and New Perspectives

The thiol (-SH) functional group is found in a number of drug compounds and confers a unique combination of useful properties. Thiol-containing drugs can reduce radicals and other toxic electrophiles, restore cellular thiol pools, and form stable complexes with heavy metals such as lead, arsenic, and copper. Thus, thiols can treat a variety of conditions by serving as radical scavengers, GSH prodrugs, or metal chelators. Many of the compounds discussed here have been in use for decades, yet continued exploration of their properties has yielded new understanding in recent years, which can be used to optimize their clinical application and provide insights into the development of new treatments. The purpose of this narrative review is to highlight the biochemistry of currently used thiol drugs within the context of developments reported in the last five years. More specifically, this review focuses on thiol drugs that represent the standard of care for their associated conditions, including N-acetylcysteine, 2,3-meso-dimercaptosuccinic acid, British anti-Lewisite, D-penicillamine, amifostine, and others. Reports of novel dosing regimens, delivery strategies, and clinical applications for these compounds were examined with an eye toward emerging approaches to address a wide range of medical conditions in the future.

Acetylcysteine in paracetamol poisoning: a perspective of 45 years of use

Paracetamol poisoning was first reported in 1966. The development of antidotes followed within 10 years, and by 1980 acetylcysteine (NAC) was acknowledged as the optimal therapy available. This article examines the history of the development of NAC and recent developments in its use. We offer suggestions for improvements in the way NAC may be administered and outline new developments that should have major impacts on the way we manage paracetamol poisoning in the near future.

First aid interventions by laypeople for acute oral poisoning

BACKGROUND

Oral poisoning is a major cause of mortality and disability worldwide, with estimates of over 100,000 deaths due to unintentional poisoning each year and an overrepresentation of children below five years of age. Any effective intervention that laypeople can apply to limit or delay uptake or to evacuate, dilute or neutralize the poison before professional help arrives may limit toxicity and save lives.

OBJECTIVES

To assess the effects of pre-hospital interventions (alone or in combination) for treating acute oral poisoning, available to and feasible for laypeople before the arrival of professional help.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, CINAHL, ISI Web of Science, International Pharmaceutical Abstracts, and three clinical trials registries to 11 May 2017, and we also carried out reference checking and citation searching.

SELECTION CRITERIA

We included randomized controlled trials comparing interventions (alone or in combination) that are feasible in a pre-hospital setting for treating acute oral poisoning patients, including but potentially not limited to activated charcoal (AC), emetics, cathartics, diluents, neutralizing agents and body positioning.

DATA COLLECTION AND ANALYSIS

Two reviewers independently performed study selection, data collection and assessment. Primary outcomes of this review were incidence of mortality and adverse events, plus incidence and severity of symptoms of poisoning. Secondary outcomes were duration of symptoms of poisoning, drug absorption, and incidence of hospitalization and ICU admission.

MAIN RESULTS

We included 24 trials involving 7099 participants. Using the Cochrane 'Risk of bias' tool, we assessed no study as being at low risk of bias for all domains. Many studies were poorly reported, so the risk of selection and detection biases were often unclear. Most studies reported important outcomes incompletely, and we judged them to be at high risk of reporting bias.All but one study enrolled oral poisoning patients in an emergency department; the remaining study was conducted in a pre-hospital setting. Fourteen studies included multiple toxic syndromes or did not specify, while the other studies specifically investigated paracetamol (2 studies), carbamazepine (2 studies), tricyclic antidepressant (2 studies), yellow oleander (2 studies), benzodiazepine (1 study), or toxic berry intoxication (1 study). Eighteen trials investigated the effects of activated charcoal (AC), administered as a single dose (SDAC) or in multiple doses (MDAC), alone or in combination with other first aid interventions (a cathartic) and/or hospital treatments. Six studies investigated syrup of ipecac plus other first aid interventions (SDAC + cathartic) versus ipecac alone. The collected evidence was mostly of low to very low certainty, often downgraded for indirectness, risk of bias or imprecision due to low numbers of events.First aid interventions that limit or delay the absorption of the poison in the bodyWe are uncertain about the effect of SDAC compared to no intervention on the incidence of adverse events in general (zero events in both treatment groups; 1 study, 451 participants) or vomiting specifically (Peto odds ratio (OR) 4.17, 95% confidence interval (CI) 0.30 to 57.26, 1 study, 25 participants), ICU admission (Peto OR 7.77, 95% CI 0.15 to 391.93, 1 study, 451 participants) and clinical deterioration (zero events in both treatment groups; 1 study, 451 participants) in participants with mixed types or paracetamol poisoning, as all evidence for these outcomes was of very low certainty. No studies assessed SDAC for mortality, duration of symptoms, drug absorption or hospitalization.Only one study compared SDAC to syrup of ipecac in participants with mixed types of poisoning, providing very low-certainty evidence. Therefore we are uncertain about the effects on Glasgow Coma Scale scores (mean difference (MD) -0.15, 95% CI -0.43 to 0.13, 1 study, 34 participants) or incidence of adverse events (risk ratio (RR) 1.24, 95% CI 0.26 to 5.83, 1 study, 34 participants). No information was available concerning mortality, duration of symptoms, drug absorption, hospitalization or ICU admission.This review also considered the added value of SDAC or MDAC to hospital interventions, which mostly included gastric lavage. No included studies investigated the use of body positioning in oral poisoning patients.First aid interventions that evacuate the poison from the gastrointestinal tractWe found one study comparing ipecac versus no intervention in toxic berry ingestion in a pre-hospital setting. Low-certainty evidence suggests there may be an increase in the incidence of adverse events, but the study did not report incidence of mortality, incidence or duration of symptoms of poisoning, drug absorption, hospitalization or ICU admission (103 participants).In addition, we also considered the added value of syrup of ipecac to SDAC plus a cathartic and the added value of a cathartic to SDAC.No studies used cathartics as an individual intervention.First aid interventions that neutralize or dilute the poison No included studies investigated the neutralization or dilution of the poison in oral poisoning patients.The review also considered combinations of different first aid interventions.

AUTHORS' CONCLUSIONS

The studies included in this review provided mostly low- or very low-certainty evidence about the use of first aid interventions for acute oral poisoning. A key limitation was the fact that only one included study actually took place in a pre-hospital setting, which undermines our confidence in the applicability of these results to this setting. Thus, the amount of evidence collected was insufficient to draw any conclusions.