Ever-increasing diversity of drug-induced pancreatitis

With over 100000 hospital admissions per annum,acute pancreatitis remains the leading gastrointestinal cause of hospitalization in the United States and has farreaching impact well beyond.It has become increasingly recognized that druginduced pancreatitis(DIP),despite accounting for less than 3%of all cases,represents an important and growing though often inconspicuous cause of acute pancreatitis.Nevertheless,knowledge of DIP is often curtailed by the limited availability of evidence needed to implicate given agents,especially for nonprescription medications.Indeed,the majority of available data is derived from case reports,case series,or case control studies.Furthermore,the mechanism of injury and causality for many of these drugs remain elusive as a definitive correlation is generally not established(<10%of cases).Several classification systems have been proposed,but no single system has been widely adopted,and periodic updates are required in light of ongoing pharmacologic expansion.Moreover,infrequently prescribed medications or those available over-thecounter(including herbal and other alternative remedies)are often overlooked as a potential culprit of acute pancreatitis.Herein,we review the ever-increasing diversity of DIP and the potential mechanisms of injury with the goal of raising awareness regarding the nature and magnitude of this entity.We believe this manuscript will aid in increasing both primary and secondary prevention of DIP,thus ultimately facilitating more expedient diagnosis and a decrease in DIPrelated morbidity.

Advances in hepatocellular carcinoma: Nonalcoholic steatohepatitis-related hepatocellular carcinoma

An increase in the prevalence of obesity and diabetes mellitus has been associated with the rise in non-alcoholic fatty liver disease(NAFLD). Two-thirds of the obese and diabetic populations are estimated to develop NAFLD. Currently, NAFLD is the most common etiology for chronic liver disease globally. The clinical spectrum of NAFLD ranges from simple steatosis, an accumulation of fat greater than 5% of liver weight, to nonalcoholic steatohepatitis(NASH), a more aggressive form with necroinflammation and fibrosis. Among the patients who develop NASH, up to 20% may advance to cirrhosis and are at risk for complications of end-stage liver disease. One of the major complications observed in patients with NASH-related cirrhosis is hepatocellular carcinoma(HCC), which has emerged as the sixth most common cancer and second leading etiology of cancer-related deaths worldwide. The incidence of HCC in the United States alone has tripled over the last three decades. In addition, emerging data are suggesting that a small proportion of patients with NAFLD may be at higher risk for HCC in the absence of cirrhosis - implicating obesity and diabetes mellitus as potential risk factors for HCC.

Advances in alcoholic liver disease:An update on alcoholic hepatitis

Alcoholic hepatitis is a pro-inflammatory chronic liver disease that is associated with high short-term morbidity and mortality(25%-35% in one month) in the setting of chronic alcohol use. Histopathology is notable for micro- and macrovesicular steatosis, acute inflammation with neutrophil infiltration, hepatocellular necrosis, perivenular and perisinusoidal fibrosis, and Mallory hyaline bodies found in ballooned hepatocytes. Other findings include the characteristic eosinophilic fibrillar material(Mallory's hyaline bodies) found in ballooned hepatocytes. The presence of focal intense lobular infiltration of neutrophils is what typically distinguishes alcoholic hepatitis from other forms of hepatitis, in which the inflammatory infiltrate is primarily composed of mononuclear cells. Management consists of a multidisciplinary approach including alcohol cessation, fluid and electrolyte correction, treatment of alcohol withdrawal, and pharmacological therapy based on the severity of the disease. Pharmacological treatment for severe alcoholic hepatitis, as defined by Maddrey's discriminant factor ≥ 32, consists of either prednisolone or pentoxifylline for a period of four weeks. The body of evidence for corticosteroids has been greater than pentoxifylline, although there are higher risks of complications. Recently head-to-head trials between corticosteroids and pentoxifylline have been performed, which again suggests that corticosteroids should strongly be considered over pentoxifylline.

Pathogenesis of hepatocarcinogenesis in non-cirrhotic nonalcoholic fatty liver disease:Potential mechanistic pathways

Although hepatocellular carcinoma(HCC) primarily arises in the background of liver cirrhosis,the development of HCC in nonalcoholic fatty liver disease(NAFLD) without cirrhosis is increasingly recognized. The pathogenesis of NAFLD associated non-cirrhotic HCC is distinct from that of cirrhotic HCC because the metabolic syndrome(MS) along with obesity and insulin resistance(IR) underlie several unique mechanisms that promote tumorigenesis. IR associated with MS,NAFLD,and type 2 diabetes mellitus lead to the release of multiple pro-inflammatory cytokines,including tumor necrosis factor alpha,interleukin-6,leptin and resistin,as well as decreased amounts of adiponectin. These processes favor the development of hepatic steatosis and inflammation within the liver,which precede HCC development. Nevertheless,further investigation is necessary to elucidate the determinants for development of HCC in patients with NAFLD in the absence of cirrhosis.

Advances in cirrhosis: Optimizing the management of hepatic encephalopathy

Hepatic encephalopathy(HE) is a major complication of cirrhosis resulting in significant socioeconomic burden, morbidity, and mortality. HE can be further subdivided into covert HE(CHE) and overt HE(OHE). CHE is a subclinical, less severe manifestation of HE and requires psychometric testing for diagnosis. Due to the time consuming screening process and lack of standardized diagnostic criteria, CHE is frequently underdiagnosed despite its recognized role as a precursor to OHE. Screening for CHE with the availability of the Stroop test has provided a pragmatic method to promptly diagnose CHE. Management of acute OHE involves institution of lactulose, the preferred first-line therapy. In addition, prompt recognition and treatment of precipitating factors is critical as it may result in complete resolution of acute episodes of OHE. Treatment goals include improvement of daily functioning, evaluation for liver transplantation, and prevention of OHE recurrence. For secondary prophylaxis, intolerance to indefinite lactulose therapy may lead to non-adherence and has been identified as a precipitating factor for recurrent OHE. Rifaximin is an effective add-on therapy to lactulose for treatment and prevention of recurrent OHE. Recent studies have demonstrated comparable efficacy of probiotic therapy to lactulose use in both primary prophylaxis and secondary prophylaxis.

Hepatitis E virus infection in the liver transplant recipients:Clinical presentation and management

Hepatitis E virus(HEV) is an emerging pathogen and an increasingly recognized cause of graft hepatitis, especially in the post-orthotopic liver transplantation immunocompromised population. The exact incidence and prevalence of HEV infection in this population remains unclear but is certainly greater than historical estimates. Identifying acute HEV infection in this population is imperative for choosing the right course of management as it is very difficult to distinguish histologically from acute rejection on liver biopsy. Current suggested approach to manage acute HEV involves modifying immunosuppression, especially discontinuing calcineurin inhibitors which are the preferred immunosuppressive agents post-orthotopic liver transplantation. The addition of ribavirin monotherapy has shown promising success rates in clearing HEV infection and is used commonly in reported cases.

Treatment strategies for chronic hepatitis C prior to andfollowing liver transplantation

Hepatitis C virus(HCV)-related liver disease is the leading indication for liver transplantation(LT) worldwide. However, HCV is an independent predictor of lower survival following LT, and recurrence of HCV postLT is virtually universal. The historic standard of care during the interferon era of HCV therapy was expectant management-initiation of antiviral therapy in the setting of documented disease progression following LT. With the advent of new direct acting antiviral(DAA) therapies for HCV, the paradigm of expectant treatment for recurrent HCV infection post-LT is shifting. The safety, tolerability, and efficacy of DAAs, even among the sickest patients with advanced liver disease, enables treatment of HCV in the pre-transplant setting among LT waitlist registrants. Finally, emerging data are supportive of preemptive therapy with DAAs in liver transplant recipients as the preferred approach. Expectant management of HCV following LT can rarely be justified in the modern era of HCV therapy.

Update on hepatitis C: Direct-acting antivirals

Hepatitis C virus(HCV) was discovered 26 years ago. For decades, interferon-based therapy has been the mainstay of treatment for HCV. Recently, several direct-acting antivirals(DAAs) have been approved for treatment of HCV-infected patients and to help combat the virus. These drugs have revolutionized the management of HCV as all-oral regimens with favorable side effect profiles and superior rates of sustained virological response. Emerging real-world data are demonstrating results comparable to registration trials for DAA agents. Suddenly, the potential for eradicating HCV is on the horizon.