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Drug-induced liver injury (DILI) due to amoxicillin-clavulanate (AC) has been associated with HLA-A*02:01, HLA-DRB1*15:01 and rs2476601, a missense variant in PTPN22. The aim of this study was to identify novel risk factors for AC-DILI and to construct a genetic risk score (GRS).Transcriptome-wide association (TWAS) and genome-wide association (GWAS) analyses were performed on 444 AC-DILI cases and 10,397 population-based controls of European descent. Associations were confirmed in a validation cohort (n=133 cases and 17,836 population-based controls). Discovery and validation AC-DILI cases were also compared to 1358 and 403 non-AC-DILI cases.TWAS revealed a significant association of AC-DILI risk with reduced liver expression of ERAP2 (P = 3.7x10We identified novel associations of AC-DILI risk with ERAP2 low expression and with HLA-B*15:18. GRS based on the five risk variants may assist AC-DILI causality assessment and risk management.

Background The aim of this study was to clarify the pathophysiology of functional dyspepsia (FD), a highly prevalent gastrointestinal syndrome, and its relationship with the better-understood syndrome of gastroparesis. Methods Adult patients with chronic upper gastrointestinal symptoms were followed up prospectively for 48 weeks in multi-center registry studies. Patients were classified as having gastroparesis if gastric emptying was delayed; if not, they were labeled as having FD if they met Rome III criteria. Study analysis was conducted using analysis of covariance and regression models. Results Of 944 patients enrolled during a 12-year period, 720 (76%) were in the gastroparesis group and 224 (24%) in the FD group. Baseline clinical characteristics and severity of upper gastrointestinal symptoms were highly similar. The 48-week clinical outcome was also similar but at this time 42% of patients with an initial diagnosis of gastroparesis were reclassified as FD based on gastric-emptying results at this time point; conversely, 37% of patients with FD were reclassified as having gastroparesis. Change in either direction was not associated with any difference in symptom severity changes. Full-thickness biopsies of the stomach showed loss of interstitial cells of Cajal and CD206+ macrophages in both groups compared with obese controls. Conclusions A year after initial classification, patients with FD and gastroparesis, as seen in tertiary referral centers at least, are not distinguishable based on clinical and pathologic features or based on assessment of gastric emptying. Gastric-emptying results are labile and do not reliably capture the pathophysiology of clinical symptoms in either condition. FD and gastroparesis are unified by characteristic pathologic features and should be considered as part of the same spectrum of truly "organic" gastric neuromuscular disorders. ClinicalTrials.gov Identifier NCT00398801, NCT01696747

Use of herbal dietary supplements (HDS) in the United States is increasing as evidenced by consumer spending that has increased annually between 1999 and 2010, with the exception of 2002 and 2003. Indeed, the amount spent on HDS in 1999 was $4 billion, increasing to $5 billion in 2010 and $5.6 billion in 2012.1–4 The actual safety and benefit of HDS, however, are questionable.5,6 Conventional drugs are required to undergo careful clinical trials and receive approval from the US Food and Drug Administration (FDA) before being marketed in the United States. In contrast, under the Dietary Supplement Health and Education Act of 1994, manufacturers of dietary supplements are themselves responsible for ensuring the safety of their products before they are released to the market (available: www.fda.gov/RegulatoryInformation/Legislation/FederalFoodDrugandCosmeticActFDCAct/SignificantAmendmentstotheFDCAct/ucm148003.htm). Scientific evidence that the products are safe and effective is required only when there is a claim for cure or for prevention of human disease. The potential for HDS to cause hepatotoxicity is confirmed by a recent report from the Drug Induced Liver Injury Network (DILIN) demonstrating that many types of HDS, particularly those used for bodybuilding, have the capacity for causing liver injury.5 The DILIN is a multicenter research network in the United States developed to study patients with hepatotoxicity owing to conventional medications and HDS. Approximately 15% of drug-induced liver injury cases ascertained by the DILIN are attributable to HDS, and there now are more than 130 cases of liver injury related to HDS in the DILIN database. The DILIN experience showed that HDS used for non–bodybuilding purposes (eg, weight loss) are associated with more severe liver injury than is the injury resulting from prescription medications. This is apparent from the finding that 13% of study participants suffering from hepatotoxicity owing to non–bodybuilding HDS required transplantation compared with only 3% of those with conventional medication–associated liver injury (P < .001).5 Importantly, the DILIN was not designed as a population-based study, so that the true incidence of liver injury in the United States owing to herbal products is yet to be established. This notwithstanding, the DILIN’s findings are particularly important against the backdrop of the current regulatory environment for HDS, which neither promotes nor mandates research on their safety or efficacy. A survey of the literature indicates that HDS-related hepatotoxicity is indeed a worldwide problem. Data from a Spanish Liver Toxicity Registry showed that HDS products accounted for 2% of all cases of identified liver injury between 1994 and 2006 and that they ranked as the 10th most common therapeutic group.7 Because of the wide use of HDS in China, India, and other countries in Southeast Asia, as well as Africa and Central America, the incidence in these countries could be much higher than it is in Western countries. This likelihood is supported by prospective studies from Korea and Singapore that reported HDS as being responsible for 73% and 71%, respectively, of all their identified cases of hepatotoxicity.8,9 The widespread use of HDS, the permissive US regulatory environment for dietary supplements, and the potential toxicity attributable to HDS give context to the need for research in this area. Little systematic investigation has been performed and an understanding of the hepatotoxic potential of HDS is limited to observational studies. Moreover, protection of the public from potentially injurious effects of HDS depends on the FDA’s ability to identify harmful products or ingredients after release to the market, and their recommendation that they then be removed from use. The approach to studying toxicity attributable to HDS is confounded by many factors. First, HDS may consist of multiple ingredients in concentrations that may vary from batch to batch. Second, multiple HDS products may be used and often combined with conventional medications, raising the possibility of interactions. Third, some HDS may cause liver injury indirectly because of chemical10 or microbial contamination and adulteration.11 More recent regulation aims to standardize current good manufacturing practices for HDS (available: www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/2007/ucm108938.htm). These factors, ostensibly barriers to research, give some direction for future studies to evaluate hepatotoxicity owing to HDS. The DILIN aims to better understand hepatotoxicity associated with HDS. As its first endeavor, it established a repository for HDS that have been linked to hepatotoxicity. Many that were implicated in liver injury have been retrieved from patients and are available for study by contacting the Chairman of the DILIN HDS Sub-committee (VN, corresponding author). As of October 1, 2014, 318 HDS products comprise this repository, collected from 119 patients, enrolled at 10 DILIN clinical sites. Already, the repository has proven itself to be an important resource for exploring the hepatotoxic potential of certain ingredients. For example, in a detailed product analysis involving green tea extracts, about 40% of products found to contain green extracts did not identify its presence on the label.12 However, no relationship was found between the concentration of green tea extract and the severity of liver injury, suggesting either that idiosyncrasy accounted for the injury or that another ingredient was responsible.12 Collaboration with scientists interested in the chemical composition of botanical products will add future value to this repository by providing the means to seek the injurious ingredients. Arguably, the greatest challenge in studying hepatotoxicity associated with HDS lies in the complexity of the products, making difficult the identification of the precise ingredient or combination of ingredients responsible for the injury. The confident identification of a toxic culprit will require labor-intensive chemical dissection of HDS into their component parts and testing each individual and combination of ingredients for potential toxicity. This task will, however, be formidable for even the most well-funded and resourceful laboratories. The lack of a conventional classification scheme or nomenclature for HDS complicates scientific investigation, because commercial HDS products may contain multiple constituents and combinations of ingredients. Thus, the DILIN has developed a nomenclature for HDS based on their primary purported marketed benefit. A structured classification for HDS will allow comparison of liver injury cases attributed to the same or similar products and identify characteristic clinical patterns of injury, unique to a given type of product or ingredient. This schema is founded on the frequency with which products were implicated by the DILIN (Table 1). Table 1 The Drug-Induced Liver Injury Network (DILIN) Herbal Dietary Supplements (HDS) Classification Scheme Based on the Primary Marketed Purpose/Use (Mutually Exclusive Categories) and Inventory in the HDS Repository Much is yet to be learned about behavioral factors that contribute to toxicity resulting from HDS. Patterns of use and overuse have not been studied and little is known of where consumers obtain information on use of products. The DILIN study offers the opportunity to expand knowledge about these features through the extensive clinical and behavioral data being collected. Claims that HDS “stimulate,” “maintain,” “support,” “regulate,” “cleanse,” or “promote” health will continue to entice consumers. However, given the now proven hepatotoxic potential of some types of products, it is the responsibility of health care providers and physician–scientists to sound the alarm and to create a research agenda to mitigate liver injury. In response to this need, a joint Workshop on Liver Injury from Herbal and Dietary Supplements will be held on May 5 and 6, 2015, at the Lister Hill Auditorium on the campus of the National Institutes of Health, cosponsored by the American Association for the Study of Liver Diseases and the National Institute of Diabetes and Digestive and Kidney Diseases. The Office of Dietary Supplements, the FDA, the Centers for Disease Control and Prevention, and the US Agriculture Department also will support the meeting. This workshop aims to bring together experts from the broad range of disciplines involved in the evaluation of HDS and define opportunities and promising directions for future research. More information about the Workshop and Fellowship Travel Awards can be found at http://www.niddk.nih.gov/news/events-calendar/Pages/Liver-Injury-Herbals-Dietary-Supplements.aspx#tab-event-details.

Background & Aims Little is known about the incidence of drug-induced liver injury (DILI) and risk factors for adverse outcomes. We evaluated short-term outcomes of a large cohort of patients with DILI enrolled in an ongoing multicenter prospective study. Methods Data were collected from 660 adults with definite, highly likely, or probable DILI. Regression methods were used to identify risk factors for early liver-related death or liver transplantation and chronic liver injury. Results Patients' median age was 51.4 years; 59.5% were female and 59.1% required hospitalization. Within 6 months of DILI onset, 30 patients received liver transplants (4.5%; 95% confidence interval [CI], 3.0%–6.1%) and 32 died (5%; 95% CI, 3.2%–6.5%); 53% of the deaths were liver related. Asian race, absence of itching, lung disease, low serum albumin levels, low platelet counts, and high serum levels of alanine aminotransferase and total bilirubin at presentation were independent risk factors for reduced times to liver-related death or liver transplantation (C-statistic = 0.87). At 6 months after DILI onset, 18.9% of the 598 evaluable subjects had persistent liver damage. African-American race, higher serum levels of alkaline phosphatase, and prior heart disease or malignancy requiring treatment were independent risk factors for chronic DILI (C-statistic = 0.71). Conclusions Nearly 1 in 10 patients die or undergo liver transplantation within 6 months of DILI onset and nearly 1 in 5 of the remaining patients have evidence of persistent liver injury at 6 months. The profile of liver injury at presentation, initial severity, patient's race, and medical comorbidities are important determinants of the likelihood of death/transplantation or persistent liver injury within 6 months.

Background & Aims The diagnosis of drug-induced liver injury relies on exclusion of other causes, including viral hepatitis A, B, and C. Hepatitis E virus (HEV) infection has been proposed as another cause of suspected drug-induced liver disease. We assessed the frequency of HEV infection among patients with drug-induced liver injury in the United States. Methods The Drug-Induced Liver Injury Network (DILIN) is a prospective study of patients with suspected drug-induced liver injury; clinical information and biological samples are collected to investigate pathogenesis and disease progression. We analyzed serum samples, collected from patients enrolled in DILIN, for immunoglobulin (Ig) G and IgM against HEV; selected samples were tested for HEV RNA. Results Among 318 patients with suspected drug-induced liver injury, 50 (16%) tested positive for anti-HEV IgG and 9 (3%) for anti-HEV IgM. The samples that contained anti-HEV IgM (collected 2 to 24 weeks after onset of symptoms) included 4 that tested positive for HEV RNA genotype 3. Samples from the 6-month follow-up visit were available from 4 patients; they were negative for anti-HEV IgM, but levels of anti-HEV IgG increased with time. Patients who had anti-HEV IgM were mostly older men (89%; mean age, 67 years), and 2 were human immunodeficiency virus positive. Clinical reassessment of the 9 patients with anti-HEV IgM indicated that acute hepatitis E was the most likely diagnosis for 7 and might be the primary diagnosis for 2. Conclusions HEV infection contributes to a small but important proportion of cases of acute liver injury that are suspected to be drug induced. Serologic testing for HEV infection should be performed, particularly if clinical features are compatible with acute viral hepatitis.

Background & Aims The Drug-Induced Liver Injury Network is conducting a prospective study of patients with DILI in the United States. We present characteristics and subgroup analyses from the first 1257 patients enrolled in the study. Methods In an observational longitudinal study, we began collecting data on eligible individuals with suspected DILI in 2004, following them for 6 months or longer. Subjects were evaluated systematically for other etiologies, causes, and severity of DILI. Results Among 1257 enrolled subjects with suspected DILI, the causality was assessed in 1091 patients, and 899 were considered to have definite, highly likely, or probable DILI. Ten percent of patients died or underwent liver transplantation, and 17% had chronic liver injury. In the 89 patients (10%) with pre-existing liver disease, DILI appeared to be more severe than in those without (difference not statistically significant; P = .09) and mortality was significantly higher (16% vs 5.2%; P 365 days were nitrofurantoin (25%) or minocycline (17%). There were no differences in outcomes of patients with short vs long latency of DILI. Compared with individuals younger than 65 years, individuals 65 years or older (n = 149) were more likely to have cholestatic injury, although mortality and rate of liver transplantation did not differ. Nine patients (1%) had concomitant severe skin reactions; implicated agents were lamotrigine, azithromycin, carbamazepine, moxifloxacin, cephalexin, diclofenac, and nitrofurantoin. Four of these patients died. Conclusions Mortality from DILI is significantly higher in individuals with pre-existing liver disease or concomitant severe skin reactions compared with patients without. Additional studies are needed to confirm the association between azithromycin and increased DILI in patients with chronic liver disease. Older age and short or long latencies are not associated with DILI mortality.

Idiosyncratic drug-induced liver injury (DILI) is a leading cause of morbidity and mortality due to medication use yet is poorly studied, in part, due to its low incidence in the general population. Identification of genetic variants associated with these uncommon and difficult to diagnose adverse events could provide clues to underlying mechanisms. Hypothesis: Common genetic variants exist that contribute to DILI susceptibility from multiple drugs. Methods: DNA obtained from 783 individuals of European ancestry who experienced DILI attributed to >200 individual drugs were genotypedwith the Illumina 1Mor 1Mduo beadchip. Source of DNA samples included the following DILI registries: DILIN (401), DILIGEN (242), EUDRAGENE (89), and Malaga (51). Genome Wide Association (GWA) was performed using population controls (n=3001). Potential associations were tested for replication in 190 independent cases from DILIN. Results: GWA revealed a strong association within the MHC region (p 108), which did not replicate in validation cohorts composed of sufficient cases due to the same drug or class. Conclusion: Our replicated association between hepatocellular DILI and STAT4 supports the emerging role of the immune system in DILI susceptibility and suggests that common genetic variation may contribute to DILI susceptibility from multiple drugs. However, the generally negative GWA results suggest that there may be a preponderance of drug-specific genetic risk factors and/or rare genetic variation underlying DILI susceptibility. Therefore, we have begun whole exome and whole genome sequencing of DILI cases caused by the most frequent drugs in our cohorts in search of rarer, high-penetrance drug-specific risk factors.

Patients with Inflammatory Bowel Disease (IBD) are at increased risk of developing colorectal cancer. The use of biomarkers to aid in the early detection and diagnosis of colorectal cancer is of interest due to their potential to improve treatment preventing further progression. Calprotectin (S100A8/S100A9) has been identified previously as a potential marker for colorectal cancer, but few studies have looked at its possible role in secondary prevention. Aim: To evaluate the potential for calprotectin in screening for, and early detection of, the transition from inflammation to dysplasia. Methods: Chronic colitis was induced in male Sprague Dawley rats by the administration of trinitrobenzene sulfonic acid (TNBS; 30 mg in 50% ethanol ic), followed six weeks later by reactivation with TNBS (5 mg/kg iv) for three days. To induce colitis-associated dysplasia the rats then received TNBS (iv) twice a week for ten weeks. A group of age-matched normal untreated animals were also included as controls. After sacrifice the colons were removed and analyzed for damage, pathology, and expression of S100A8 and S100A9were measured by real time RT-PCR. Tissue distribution of the S100 proteins was measured by immunohistochemistry. Results: Administration of TNBS caused ulceration and damage as expected, which correlated with the pathological diagnosis. Animals diagnosed with dysplasia had the highest macroscopic damage (p

Background & Aims Idiosyncratic drug-induced liver injury (DILI) is among the most common causes of acute liver failure in the United States, accounting for approximately 13% of cases. A prospective study was begun in 2003 to recruit patients with suspected DILI and create a repository of biological samples for analysis. This report summarizes the causes, clinical features, and outcomes from the first 300 patients enrolled. Methods Patients with suspected DILI were enrolled based on predefined criteria and followed up for at least 6 months. Patients with acetaminophen liver injury were excluded. Results DILI was caused by a single prescription medication in 73% of the cases, by dietary supplements in 9%, and by multiple agents in 18%. More than 100 different agents were associated with DILI; antimicrobials (45.5%) and central nervous system agents (15%) were the most common. Causality was considered to be definite in 32%, highly likely in 41%, probable in 14%, possible in 10%, and unlikely in 3%. Acute hepatitis C virus (HCV) infection was the final diagnosis in 4 of 9 unlikely cases. Six months after enrollment, 14% of patients had persistent laboratory abnormalities and 8% had died; the cause of death was liver related in 44%. Conclusions DILI is caused by a wide array of medications, herbal supplements, and dietary supplements. Antibiotics are the single largest class of agents that cause DILI. Acute HCV infection should be excluded in patients with suspected DILI by HCV RNA testing. The overall 6-month mortality was 8%, but the majority of deaths were not liver related.

The EGFR is overexpressed in many tumors including pancreatic exocrine cancers. Whether it is overexpressed in pancreatic endocrine tumors (PETs) such as gastrinomas is unclear. In one report all gastrinomas expressed EGFR, whereas with other PETs EGFR was only rarely expressed. Because overexpression of EGFR is associated with poor prognosis in many tumors, and a proportion of gastrinomas are aggressive, the expression of EGFR may have prognostic significance. To address this question the following study was performed. Gastrinomas from 16 patients with Zollinger-Ellison syndrome were examined for EGFR expression and the expression was compared to the tumor growth. Competitive RT-PCR and immunohistochemistry were performed on 10 gastrinomas each. Paraffin-embedded sections were stained using 3 different monoclonal antibodies. Breast cancer specimens served as positive controls. mRNA levels were assessed by competitive RT-PCR with mRNA-specific primers. EGFR mRNA levels were normalized for b-actin mRNA levels and expressed as the ratio between the two. Pooled mRNA fractions from normal human pancreatic tissue were used as normal controls. Sixteen gastrinomas (6M, 10F), 14 sporadic tumors and 2 MEN-l associated gastrinomas were analyzed. The mean age of the patients was 43.6±0.4 yr [15.5-65.3). The mean fasting serum gastrin level was 5934±2018 pglml [404-26667]. The mean follow-up was 5.3±0.7 yr [0.9-11.2). Five patients had aggressive disease. All tumors expressed EGFR mRNA. The mean EGFRIb-actin ratio of the gastrinomas was lower than that of normal pancreatic tissue (0.0085±0.OO24 vs. 0.055±0.025). In none of the 10 gastrinomas did the ratio exceed that found in normal pancreas. The mean EGFRIb-actin ratio did not differ between aggressive (n=5) and benign (n=5) gastrinomas (0.040±0.035 vs. 0.0115±0.004). The EGFRIb-actin ratio did not differ between duodenal gastrinomas (n=5) and primary tumors in another location (n=4), (0.011±0.004 vs. 0.OO6±0.OO2). Immunostaining for EGFR was negative in each of the 10 tumors tested. The results show that the EGFR is expressed in all gastrinomas, however it is not overexpressed compared to normal pancreatic tissue. Furthermore its level of expression does not correlate with the aggressiveness of the tumor or with the primary location of the tumor, which has been shown to be an important determinant of metastatic potential. These results suggest that in contrast to exocrine pancreatic tumors, in PETs overexpression of EGFR is unlikely to be an important pathogenic process.

Markedly decreased acid secretion is known to decrease vitamin B~2 absorption. However, it is controversial whether prolonged treatment with potent gastric antisecretory drugs will caused decreased serum vitamin Btz levels (Bt2 levels). This could be a potentially important problem in conditions such as GERD or ZES, requiring continuous long-term treatment. In a previous study we reported that B~z levels, but not serum folate levels, determined at one time correlated inversely with the length of omeprazole treatment in patients with ZES. In the present study to provide insights into the possible effects of long-term acid suppression on B~2 levels in a given patient, we have analyzed sequential results from 68 patients with ZES who were followed for at least 5 years. Patients had yearly B~ levels and determinations of acid secretory control taken one hour before the next dose of antisecretory drug. The mean age of the patients was 55 ± 1 yrs, there were 22 females and 46 males, and the total duration of gastric antisecretory treatment was 14 _+0.5 yrs. Fifty-two patients were being treated with omeprazole (mean time ± 1SEM=5 ± 1 yrs) and 17 patients with histamine Hz inhibitors. The mean initial B~2 level was 439 ± 21 pg/ml (normal=165-1000 pg/ml) and the last Ba2 level, a mean of 6.3 ± 1.2 yrs later, was 427 ± 21 pg/ml, was not significantly different. The patients had a mean basal acid output of 25 ± 2 mEq/h and M An of 54-+ 4 mEq/h. The patients' acid secretory rate on antisecretory drug for each of the last 5 years was reviewed and 21/68 (30%) had complete achlorhydria defined as no basal acid secretion during each of the last 3 years. The B~ levels over the 6.3 ± 1.1 yrs from the first to the last Bl~ level in the achlorhydric patients showed a highly significant (p=0.001) decrease from 419 _+ 38 to 305 ± 24 pg/ml. In contrast, for the 47 patients without complete achlorhydria over a 6.3 ± 1.2 year period of antisecretory drug treatment, the B~2 levels did not change significantly (447 ± 26 vs 480 ± 35 pg/ml). A significantly higher proportion (p=0.002) [18/21 (86%)] of patients with complete achlorhydria had a decrease in their B~2 levels over this time period compared to the patients without achlorhydria [22/47 (47%)]. These results demonstrate that profound acid inhibition, which occurs in 32% of patients with ZES, lead to a highly significant decrease in serum vitamin levels over a 6-year period. In other studies > 80% of patients with GERD treated long-term with potent antisecretory drugs also have such acid hyposecretion that hypergastrinemia develops. These results suggest that in patients with such conditions as ZES or GERD undergoing prolonged daily treatment with potent gastric acid suppressants such as omeprazole or lansoprazole, routine monitoring of B~2 levels should be considered.