Refinement of decision tree to assess the consequences of increased serum ALP in dogs: Additional analysis on toxicity studies of pesticides evaluated recently in Japan.

Recently we provided a new interpretation that increased serum ALP in dogs is not adverse if no hepatotoxic finding coexists in the analysis of toxicity studies of over 200 pesticides evaluated in Japan (Yokoyama et al., 2019). We also proposed a decision tree to evaluate the adversity of the increased ALP. The present analysis was conducted to validate the reliability of this interpretation with 129 pesticides more recently evaluated. Before applying, the decision tree was revised to be consistent in all steps. The pesticides showed similar characterization of increased ALP to the previous analysis in that the increase was more frequent than in rats and that liver hypertrophy and hepatotoxicity commonly coexisted with an increase in ALP in dogs. When short- and long-term studies of 58 pesticides inducing ALP activity in dogs were applied to the revised tree, the increased ALP in 8 pesticides was judged not adverse in either study. The revision of the tree did not affect the NOAEL judgment of these pesticides; however, the revised routes contributed to the judgment more robustly. This study showed the reliability of our interpretation and applicability of the decision tree to evaluate the adversity of increased ALP in dogs.

The MicroRNA-based Liquid Biopsy Improves Early Assessment of Lethal Acetaminophen Poisoning: A Case Report.

BACKGROUND Acetaminophen overdose is the most common cause of acute liver failure. Nevertheless, new biomarker approaches enabling early prediction of the outcome of the acetaminophen overdose are needed. Recently, using next-generation sequencing analysis of serum from human study participants we uncovered injury-specific signatures of circulating microRNAs (miRNAs) that represented underlying molecular mechanisms of toxicity. This case study is first to show the application of miRNA profiling to assess prognosis of acetaminophen poisoning. CASE REPORT The patient was admitted to the hospital following supra therapeutic acetaminophen ingestion. The patient showed elevated levels of biomarkers of hepatocellular injury alanine aminotransferase, aspartate transaminase, and glutamate dehydrogenase. Even though treatment with N-acetyl cysteine was initiated 24 hours post-ingestion, levels of alanine-aminotransferase and aspartate transaminase peaked at about 40 hours post ingestion of acetaminophen. We analyzed global circulating miRNA levels from 24 consecutive serum samples from this study participant covering the period from admission to time of death. CONCLUSIONS The resulting global miRNA profiles were compared with profiles from study participants with non-lethal acetaminophen poisoning and healthy controls. At the admission, the miRNA profiles of both lethal and non-lethal acetaminophen poisoning showed induction of cellular stress and oxidative damage. Later, the miRNA profiles of the lethal poisoning featured fibrosis and coagulation pathways while profiles of non-lethal cases resembled those of healthy study participants. Although additional confirmatory studies are needed, our case study is first to indicate that global miRNA profiles to be used as liquid biopsies have potential to facilitate the assessment of acetaminophen poisoning.

Assessment of the protective and therapeutic effect of melatonin against thioacetamide-induced acute liver damage.

Acute or chronic damage to the liver may occur through alcohol, drugs, viruses, genetic disorders, and toxicity. In this study, we planned to investigate the protective and therapeutic effects of melatonin (Mel) by causing damage to the liver with thioacetamide (TAA). Thirty-five rats were used. Group I: control group (seven pieces), group II: Mel group (seven pieces) the single dose on the first day of the experiment was 10 mg/kg, group III: TAA (seven pieces) 300 mg/kg with 24-hour intervals, two doses, group IV: Mel + TAA group (seven pieces) 10 mg/kg single dose Mel was applied 24 hours before TAA application, group V: TAA + Mel group (seven pieces) single dose (24th hour) of 10 mg/kg Mel was administered after TAA (300 mg/kg) two doses. The liver histology was evaluated. Apoptosis, autophagy, and necrosis markers in tissue were determined by immunohistochemistry. Aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) levels in blood serum samples and transforming growth factor-ß (TGF-ß) and tumor necrosis factor-α (TNF-α) levels were determined in liver tissue. TAA affected histologically the classical lobule structure both in cell cords and sinusoids. Caspase-3, RIP3, and LC3 levels were increased in group III compared with the control group. TAA did not cause a statistically significant change in TNF-α level but decreased the TGF-ß level significantly. AST and ALT levels were statistically significant in group II and V compared with group I, the ALP level was significant in group IV compared with group II. The results of this study showed that TAA caused significant damage to tissues and increased cell death, Mel was found to have more therapeutic than the protective effect on tissues.

Assessment of Serious Acute and Chronic Idiosyncratic Drug-Induced Liver Injury in Clinical Practice.

Drug-induced liver injury (DILI) is the leading cause of acute liver failure (ALF) in developed countries. The extremely variable phenotype of DILI, both in presentation and in severity, is one of the distinctive characteristics of the disease and one of the major challenges that hepatologists face when assessing hepatotoxicity cases. A new Hy's law that more accurately predicts the risk of ALF related to DILI has been proposed and validated. Other prognostic scoring algorithms for the early identification of DILI patients who may go on to develop ALF have been developed as it is of most clinical relevance to stratify patients for closer monitoring. Recent data indicate that acute DILI often presents a more prolonged resolution or evolves into chronicity at a higher frequency than other forms of acute liver injury. Risk factors for chronicity, specific phenotypes, and histological features are discussed in this study. Biomarkers to predict DILI outcome are in need.

Agreement Among Different Scales for Causality Assessment in Drug-Induced Liver Injury.

BACKGROUND AND OBJECTIVE: The causality assessment of drug-induced liver injury (DILI) remains a challenge and eagerly awaits the development of reliable hepatotoxicity biomarkers. None of the different available algorithms used for the causality assessment of DILI has been universally accepted as the gold standard. This study was conducted to examine the agreement among different causality assessment scales in reporting DILI. METHODS: The World Health Organization-Uppsala Monitoring Center (WHO-UMC), Naranjo, Roussel Uclaf Causality Assessment Method (RUCAM), Maria & Victorino (M & V) and Digestive Disease Week-Japan (DDW-J) assessment scales were used to compare the causalities in all the reported cases of DILI in our adverse drug reaction (ADR) monitoring centre from January 2014 to June 2017. The probability of the causality assessment was classified as 'definite', 'probable', 'possible' and 'unlikely'. The agreement obtained among the causality assessments was analysed using the weighted kappa (κ w) test. RESULTS: A total of 33 cases of DILI were included in our analyses. Anti-tubercular therapy (ATT) and methotrexate were the drugs that most commonly caused DILI. The overall agreement among the different scales was poor. The best agreement was found between RUCAM and DDW-J scales (κ w: 0.685). CONCLUSION: There were discrepancies among the different causality scales in assessing DILI. This might be due to the different definitions of causality criteria and subjective variability during assessment. A personalised assessment scale incorporating the latest information on specific risk factors and evidence-based criteria for DILI is warranted.

Assessment of liver function in pregnant anemic women upon oral iron and folic acid supplementation.

Oral iron therapy is the most widely prescribed treatment for iron deficiency anemia. However, oral iron supplementation may also lead to various health problems. The recognition of these physiological variations is essential for the diagnosis of liver diseases during the course of pregnancy. Therefore, the objective of this study was to assess the variations in levels of routine liver function tests (LFTs) in pregnant women before and after iron and folic acid treatment. Iron and folic acid was supplemented to 500 normal pregnant anemic women (mild=200, moderate=200 and severe=100) and 100 age matched normal pregnant non-anemic as controls daily for 100 days. Blood index values and liver function parameters were precisely monitored. Hemoglobin (Hb), total protein (TP), iron (Fe), albumin and alkaline phosphatase (ALP) levels were found increased (P<0.001; P<0.01; P<0.05) after treatment in mild, moderate, severe and control, respectively. Lipid peroxidation (LPx), aspartate transaminase (AST) and alanine transaminase (ALT) were increased in pretreated mild, moderate and severe groups and further increased after all treated subjects. Moreover, gamma-glutamyl transpeptidase (GGT) was found to decrease in pre and posttreated subjects. Treatment with iron and folic acid although has remarkable efficacy for Hb and body iron stores although for the cost of increasing the associated compartment of total bilirubin, AST and ALT concomitant with decreased GGT levels. Data obtained from the present study provide new insights into the mandatory application of liver function tests likely to be monitored at regular and specific intervals during the course of pregnancy.

The transformation in biomarker detection and management of drug-induced liver injury.

Drug-induced liver injury (DILI) is a major concern for patients, care givers and the pharmaceutical industry. Interpretation of the serum biomarkers routinely used to detect and monitor DILI, which have not changed in almost 50 years, can be improved with recently proposed models employing quantitative systems pharmacology. In addition, several newer serum biomarkers are showing great promise. Studies in rodents indicate that the ratio of the caspase cleaved fragment of cytokeratin 18 to total K18 in serum (termed the "apoptotic index") estimates the relative proportions of apoptosis vs necrosis during drug-induced liver injury. Glutamate dehydrogenase can reliably differentiate liver from muscle injury and, when serum is properly prepared, may also detect mitochondrial toxicity as a mechanism of liver injury. MicroRNA-122 is liver-specific, but recent data suggests it can be actively released from hepatocytes in the absence of overt toxicity limiting enthusiasm for it as a DILI biomarker. Finally, damage associated molecular patterns, particularly high mobility group box 1 and its various modified forms, are promising biomarkers of innate immune activation, which may be useful in distinguishing benign elevations in aminotransferases from those that portend clinically important liver injury. These new biomarkers are already being measured in early clinical trials, but broad acceptance will require widespread archiving of serum from diverse clinical trials and probably pre-competitive analysis efforts. We believe that utilization of a panel of traditional and newer biomarkers in conjunction with quantitative systems pharmacology modelling approaches will transform DILI detection and risk management.

Drug-induced liver injury: recent advances in diagnosis and risk assessment.

Idiosyncratic drug-induced liver injury (IDILI) is a rare but potentially severe adverse drug reaction that should be considered in patients who develop laboratory criteria for liver injury secondary to the administration of a potentially hepatotoxic drug. Although currently used liver parameters are sensitive in detecting DILI, they are neither specific nor able to predict the patient's subsequent clinical course. Genetic risk assessment is useful mainly due to its high negative predictive value, with several human leucocyte antigen alleles being associated with DILI. New emerging biomarkers which could be useful in assessing DILI include total keratin18 (K18) and caspase-cleaved keratin18 (ccK18), macrophage colony-stimulating factor receptor 1, high mobility group box 1 and microRNA-122. From the numerous in vitro test systems that are available, monocyte-derived hepatocytes generated from patients with DILI show promise in identifying the DILI-causing agent from among a panel of coprescribed drugs. Several computer-based algorithms are available that rely on cumulative scores of known risk factors such as the administered dose or potential liabilities such as mitochondrial toxicity, inhibition of the bile salt export pump or the formation of reactive metabolites. A novel DILI cluster score is being developed which predicts DILI from multiple complimentary cluster and classification models using absorption-distribution-metabolism-elimination-related as well as physicochemical properties, diverse substructural descriptors and known structural liabilities. The provision of more advanced scientific and regulatory guidance for liver safety assessment will depend on validating the new diagnostic markers in the ongoing DILI registries, biobanks and public-private partnerships.

The chronic hepatotoxicity assessment of the herbal formula Zishen Yutai pill.

Zishen Yutai pill (ZYP) is an oriental herbal formula, while hepatotoxicity assessment of ZYP was rarely evaluated. Therefore, our aim is to re-evaluate its hepatotoxicity in both normal and carbon tetrachloride (CCl4) induced chronic liver injury rats. In the normal model, two doses of ZYP (1.575 and 9.450 g kg-1 d-1; i.e. 1 × , 6 × clinical doses) were given orally to rats for 24 weeks. In the chronic liver injury model, 10% CCl4 was administered to rats abdominally twice a week at a dose of 5 mL kg-1 for 12 consecutive weeks. Administration time started from 4 weeks after the beginning of CCl4 treatment. Toxicological parameters included mortality, body weight, food consumption, clinical signs, biochemical parameters, gross observation, organ weight, necropsy findings and histopathology were monitored. In the normal model, we found no any mortality or abnormality in clinical signs, relative liver weight, biochemical parameters and histopathology in ZYP treatment groups. In the chronic liver injury model, liver damage related parameter such as ALT was elevated at the high dose of ZYP treatment in contrast to the CCl4-treated group (P < 0.01). In histopathological assessment, there were no significant difference between ZYP treatment groups and CCl4-treated group. No observed adverse effect on livers were established for 9.450 g kg-1 d-1 ZYP in the normal rats and 9.450 g kg-1 d-1 ZYP in the injury rats.

Pharmacological safety evaluation of a traditional herbal medicine "Zereshk-e-Saghir" and assessment of its hepatoprotective effects on carbon tetrachloride induced hepatic damage in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: "Zereshk-e-Saghir" (ZES), one of the traditional herbal medicines in old manuscripts of Persian hakims, has been used for the treatment of liver disorders. This current study is aimed to evaluate ZES effects on animal model to investigate its safety and hepatoprotective activity. MATERIALS AND METHODS: ZES was prepared according to a traditional method by blending aqueous extracts of Berberis vulgaris L., with fine particles of other plants including Rosa damascene Mill, Cichorium intybus L., Cucumis sativus L., Portulaca oleracea L., Rheum palmatum L., and Nardostachys jatamansi DC.. The lethality of ZES was determined in male NMRI mice. Acute organ toxicity of ZES (750 and 1500mg/kg for 15 days, orally) was evaluated by measuring the cell blood count, liver marker enzymes, creatinine, antioxidant status and histopathological examinations in rats. CCl4-induced liver toxicity was used to examine the hepatoprotective effects of the preparation. The rats were pretreated with 250, 500, 750 and 1500mg/kg ZES by gavage for 15 days. At day 16, the rats were intraperitoneally injected 1ml/kg CCl4 in olive oil. Forty-eight hours after CCl4 injection, the animals were sacrificed and their liver samples and blood were collected for determination of alanine aminotransferase, aspartate aminotransferase and alkaline phosphatase (ALT, AST, and ALP), histopathological examinations and antioxidant status. RESULTS: Treatment of the mice with a single dose of ZES up to 2g/kg did not cause mortality. Treatment of the rats with doses of 750 and 1500mg/kg for 15 days showed no significant hematotoxicity and hepatotoxicity. Treatment of the rats with ZES reduced the increased serum levels of ALT, AST, and ALP induced by CCl4 at the doses of 250, 500, and 750mg/kg. This was almost confirmed by histopathological examinations. Pretreatment with ZES also decreased lipid peroxidation and maintained the levels of glutathione and total antioxidant capacity. CONCLUSIONS: The present in vivo study revealed that the long term usage of ZES was safe for organs in laboratory animals. Meanwhile, prescribing the traditionally-recommended dose of ZES can be probably used against the liver injuries induced by xenobiotics. Further studies in other models of liver injuries are recommended for finding the exact hepatoprotective mechanism of ZES.

AN ASSESSMENT OF THE FERROKINETIC INDICES IN RATS WITH TOXIC HEPATITIS UNDER THE CONDITIONS OF ALIMENTARY DEPRIVATION OF PROTEIN.

The ferrokinetic indices of blood serum of rats with acetaminophen-induced hepatitis under the conditions of alimentary deprivation of protein were assessed in the work. Research was conducted on 4 groups of animals: 1 - control; 2 - rats maintained on low-protein diet; 3 - rats with acute acetaminophen-induced hepatitis, maintained on full-value ration, 4 - rats with acute acetaminophen-induced hepatitis, maintained under the conditions of alimentary deprivation of protein. The serum iron content of and serum iron binding capacity were determined colorimetrically,% of the transferrin iron saturation - as a ratio of serum iron concentration to maximal iron binding capacity of serum transferrin. The presence of hemosiderin inclusions and the character of hemosiderosis were determined in the liver sections, stained by Perls method. Qualitative determination of C-reactive protein in blood serum was carried out by immunoenzymatic method. It is shown, that in protein-deficiency rats any significant changes of iron metabolism indices and hemosiderin accumu- lation weren't observed. At the same time in rats with acetaminophen-induced hepatitis the 5-fold increase of the serum iron content against the background non-significant increase of serum iron binding capacity and the 2-fold increase of the transferrin iron saturation is established. Simultaneously in the hepatocytes and reticuloendothelial system cells the accumulation of hemosiderin in the low dispersion form is observed, equating the second degree of hemosiderosis on the background emerging of C-reactive protein in serum. In protein-deficiency rats with toxic liver injury an abrupt increase of serum iron against the background reduction of the total serum iron binding capacity and maximal saturation of transferrin by iron ions is observed. It is established, that for animals from current group the third degree of mixed type hemosiderosis and the intensification of the inflammatory reaction in liver is characterstic. Conclusion was made, that alimentary deprivation of protein under the conditions of toxic liver injury is the critical factor for structural-functional state of liver, being accompanied by the iron metabolism disturbances, development of hemosiderosis and intensification of the inflammatory reaction in liver. Research results may be used for the biochemical rationale of the therapeutic approaches for the elimination and correction of the toxic liver injury consequences.

Contrast-enhanced micro-computed tomography using ExiTron nano6000 for assessment of liver injury.

AIM: To explore the potential of contrast-enhanced computed tomography (CECT) using ExiTron nano6000 for assessment of liver lesions in mouse models. METHODS: Three mouse models of liver lesions were used: bile duct ligation (BDL), lipopolysaccharide (LPS)/D-galactosamine (D-GalN), and alcohol. After injection with the contrast agent ExiTron nano6000, the mice were scanned with micro-CT. Liver lesions were evaluated using CECT images, hematoxylin and eosin staining, and serum aminotransferase levels. Macrophage distribution in the injury models was shown by immunohistochemical staining of CD68. The in vitro studies measured the densities of RAW264.7 under different conditions by CECT. RESULTS: In the in vitro studies, CECT provided specific and strong contrast enhancement of liver in mice. CECT could present heterogeneous images and densities of injured livers induced by BDL, LPS/D-GalN, and alcohol. The liver histology and immunochemistry of CD68 demonstrated that both dilated biliary tracts and necrosis in the injured livers could lead to the heterogeneous distribution of macrophages. The in vitro study showed that the RAW264.7 cell masses had higher densities after LPS activation. CONCLUSION: Micro-CT with the contrast agent ExiTron nano6000 is feasible for detecting various liver lesions by emphasizing the heterogeneous textures and densities of CECT images.

Liver biomarker and in vitro assessment confirm the hepatic origin of aminotransferase elevations lacking histopathological correlate in beagle dogs treated with GABAA receptor antagonist NP260.

NP260 was designed as a first-in-class selective antagonist of α4-subtype GABAA receptors that had promising efficacy in animal models of pain, epilepsy, psychosis, and anxiety. However, development of NP260 was complicated following a 28-day safety study in dogs in which pronounced elevations of serum aminotransferase levels were observed, although there was no accompanying histopathological indication of hepatocellular injury. To further investigate the liver effects of NP260, we assayed stored serum samples from the 28-day dog study for liver specific miRNA (miR-122) as well as enzymatic biomarkers glutamate dehydrogenase and sorbitol dehydrogenase, which indicate liver necrosis. Cytotoxicity assessments were conducted in hepatocytes derived from dog, rat, and human liver samples to address the species specificity of the liver response to NP260. All biomarkers, except ALT, returned toward baseline by Day 29 despite continued drug treatment, suggesting adaptation to the initial injury. In vitro analysis of the toxicity potential of NP260 to primary hepatocytes indicated a relative sensitivity of dog>human>rat, which may explain, in part, why the liver effects were not evident in the rodent safety studies. Taken together, the data indicate that a diagnostic biomarker approach, coupled with sensitive in vitro screening strategies, may facilitate interpretation of toxicity potential when an adaptive event masks the underlying toxicity.

Circulating microRNAs in drug safety assessment for hepatic and cardiovascular toxicity: the latest biomarker frontier?

Drug-induced liver and cardiovascular injuries are important aspects of safety evaluations of numerous drugs in development. Therefore, reliable and predictive biomarkers to allow detection of early signs of drug-induced liver and cardiovascular injuries are required in clinical and preclinical pharmaceutical evaluation. MicroRNAs (miRNAs) are reported to be present in body fluids (blood, urine, etc.), and these 'circulating miRNAs' have been proposed as toxicological biomarkers of drug-induced tissue injury in preclinical and clinical practice. To be used as biomarkers of drug toxicity, such miRNAs need to show rapid and injured-tissue-specific upregulation in body fluids after injury, be more sensitive than existing protein markers such as alanine aminotransferase (ALT) and troponins, and be able to identify the toxicants responsible, if possible. In this article, we focus on the current knowledge of circulating miRNAs, which have potential for use in assessment of drug-induced liver and cardiovascular injuries. In addition, we discuss an important question regarding normalization of the expression levels of certain circulating miRNAs in body fluids.

Potential protective effect of sunitinib after administration of diclofenac: biochemical and histopathological drug-drug interaction assessment in a mouse model.

Sunitinib is a tyrosine kinase inhibitor for GIST and advanced renal cell carcinoma. Diclofenac is used in cancer pain management. Coadministration may mediate P450 toxicity. We evaluate their interaction, assessing biomarkers ALT, AST, BUN, creatinine, and histopathological changes in the liver, kidney, heart, brain, and spleen. ICR mice (male, n = 6 per group/dose) were administered saline (group A) or 30 mg/kg diclofenac ip (group B), or sunitinib po at 25, 50, 80, 100, 140 mg/kg (group C) or combination of diclofenac (30 mg/kg, ip) and sunitinib (25, 50, 80, 100, 140 mg/kg po). Diclofenac was administered 15 min before sunitinib, mice were euthanized 4 h post-sunitinib dose, and biomarkers and tissue histopathology were assessed. AST was 92.2 ± 8.0 U/L in group A and 159.7 ± 14.6 U/L in group B (p < 0.05); in group C, it the range was 105.1-152.6 U/L, and in group D, it was 156.0-209.5 U/L (p < 0.05). ALT was 48.9 ± 1.6 U/L (group A), 95.1 ± 4.5 U/L (p < 0.05) in group B, and 50.5-77.5 U/L in group C and 82.3-115.6 U/L after coadministration (p < 0.05). Renal function biomarker BUN was 16.3 ± 0.6 mg/dl (group A) and increased to 29.9 ± 2.6 mg/dl in group B (p < 0.05) and it the range was 19.1-33.3 mg/dl (p < 0.05) and 26.9-40.8 mg/dl in groups C and D, respectively. Creatinine was 5.9 pmol/ml in group A; 6.2 pmol/ml in group B (p < 0.01), and the range was 6.0-6.2 and 6.2-6.4 pmol/ml in groups C and D, respectively (p < 0.05 for D). Histopathological assessment (vascular and inflammation damages) showed toxicity in group B (p < 0.05) and mild toxicity in group C. Damage was significantly lesser in group D than group B (p < 0.05). Spleen only showed toxicity after coadministration. These results suggest vascular and inflammation protective effects of sunitinib, not shown after biomarker analysis.

Exposure to solvents in health care workers: assessment of the hepatic effects.

OBJECTIVES: The use of organic solvents has been linked to pathologies of different apparatuses. The purpose of this study is to analyze the liver damage induced by organic solvents. MATERIALS AND METHODS: We analyzed 556 workers, 278 exposed to organic solvents (group 1) and 278 not exposed to organic solvents (group 2). The exposed group was further divided into 2 subgroups: group 1A (139 workers exposed to considerable doses) and group 1B (139 workers exposed to negligible doses). Mean and standard deviation of some liver parameters was calculated. Statistically significant differences between the liver parameters in the different groups and subgroups were detected using the t-test. Multiple linear regression models were used to examine the associations between laboratory parameters and the independent variable. RESULTS: The data so far obtained showed the existence of statistically significant differences with regard to the total protein, total bilirubin, transaminase GOT and GPT, Gamma Glutamyl Transferase (gamma-GT). CONCLUSIONS: Our results confirm that exposure to solvents can alter some liver parameters. The blood tests we used can be useful tool for the assessment of the actual occupational hazards and to verify the effectiveness of the measures taken for the prevention and protection.

Assessment of emerging biomarkers of liver injury in human subjects.

Hepatotoxicity remains a major challenge in drug development. Although alanine aminotransferase (ALT) remains the gold standard biomarker of liver injury, alternative biomarker strategies to better predict the potential for severe drug-induced liver injury (DILI) are essential. In this study, we evaluated the utility of glutamate dehydrogenase (GLDH), purine nucleoside phosphorylase (PNP), malate dehydrogenase (MDH), and paraxonase 1 (PON1) as indicators of liver injury in cohorts of human subjects, including healthy subjects across age and gender, subjects with a variety of liver impairments, and several cases of acetaminophen poisoning. In the healthy subjects, levels of GLDH and MDH were not affected by age or gender. Reference ranges for GLDH and MDH in healthy subjects were 1-10 and 79-176U/L, respectively. In contrast, the levels of PON1 and PNP were not consistent across cohorts of healthy subjects. Furthermore, GLDH and MDH had a strong correlation with elevated ALT levels and possessed a high predictive power for liver injury, as determined by ROC analysis. In contrast, PON1 and PNP did not detect liver injury in our study. Finally, evaluation of patients with acetaminophen-induced liver injury provided evidence that both GLDH and MDH might have utility as biomarkers of DILI in humans. This study is the first to evaluate GLDH, MDH, PON1, and PNP in a large number of human subjects and, and it provides an impetus for prospective clinical studies to fully evaluate the diagnostic value of GLDH and MDH for detection of liver injury.

Paracetamol toxicity: What would be the implications of a change in UK treatment guidelines?

BACKGROUND: Treatment of single-time-point ingestion acute paracetamol (acetaminophen) poisoning with N-acetylcysteine (NAC) is guided by plotting a timed plasma paracetamol concentration on established nomograms. Guidelines in the UK differ from those in the U.S. and Australasia by having two treatment lines on the nomogram. Patients deemed to be at 'normal' risk of hepatotoxicity are treated using the treatment line starting at 200 mg/L at 4 h post-ingestion; those at higher risk are treated using the 'high risk' treatment line starting at 100 mg/L at 4 h post-ingestion. AIM: To examine the effect on treatment numbers if UK guidelines were to adopt a single treatment line nomogram or lower, risk-stratified treatment lines. METHODS: We undertook a retrospective analysis of a series of acute single-time-point paracetamol poisonings presenting to our inner city emergency department. Treatment numbers and effect on treatment costs were modelled for three alternative scenarios: a 150 line-a combined single treatment line starting at a 4 h concentration of 150 mg/L, a 100 line-a combined single treatment line starting at a 4 h concentration of 100 mg/L, and a 150/75 line-a double treatment line at the lower concentrations of 150 mg/L for normal risk and 75 mg/L for high risk patients. RESULTS: A total of 1,214 cases were identified. Under current UK guidance, 133 (11.0%) high risk cases and 98 (8.1%) normal risk cases needed treatment (total 231, 19.0%). A 150 line would result in 87 (7.2%) high risk cases and 155 (12.8%) normal risk cases needing treatment (total 242, 19.9%). A 100 line would result in 133 (11.0%) high risk and 251 (20.7%) normal risk cases needing treatment (total 384, 31.6%). A 150/75 line would result in 153 (12.6%) high risk and 155 (12.8%) normal risk cases needing treatment (total 308, 25.4%). CONCLUSIONS: Both a 100 line and a 150/75 line would result in a large increase in the number of patients being treated and an associated increase in the costs of treatment. A single 150 mg/L treatment line would simplify treatment algorithms and lead to a similar number of patients being treated with NAC overall. A potential concern however is whether any of the high risk cases that would no longer be treated might develop significant hepatotoxicity. After consideration of the evidence for dual treatment lines, we feel that these risks are small and that it is worth reconsidering a change of treatment recommendations to a single 150 line.