Review Articles in 2010

Clostridium difficileis as an important health-care-associated pathogen and is linked to significant morbidity, economic burden, and even mortality. A dramatic rise in the incidence ofC. difficileinfections has occurred over the past decade and new at-risk populations are emerging. This Review discusses recent changes in the epidemiology of CDI and its risk factors, examines the evidence behind various treatment regimens and management strategies and suggests measures for infection control.

Nonalcoholic fatty liver disease (NAFLD) and/or nonalcoholic steatohepatits can take decades to evolve and progress, which limits the quality of longitudinal data. Researchers have, therefore, turned their attention to the development of suitable animal models to test the role of molecules and molecular pathways in the progression of fatty liver formation. This Review discusses the benchmark animal models that recapitulate the pathology and metabolic dysfunction associated with NALFD.

Epiploic appendagitis is a very rare condition that results from inflammation of an epiploic appendage in the colon. Gastroenterologists and all medical personnel should be aware of this condition, which mimics many other intra-abdominal acute and subacute conditions. In this Review article, Schnedl and colleagues discuss the clinical findings epiploic appendagitis, its pathophysiology, diagnosis, and treatment.

Pancreatic cancer is a highly aggressive malignancy, which is partly attributable to drug resistance. This Review summarizes the current knowledge of the biological significance of the epithelial–mesenchymal transition, cancer stem cells and microRNAs in the context of drug resistance in patients with pancreatic cancer and describes how this knowledge could be applied to overcoming chemoresistance in pancreatic cancer.

The latest genome-wide association studies in large cohorts of patients with a range of liver diseases have provided new insights into the pathophysiology of these illnesses. This Review outlines the role of genetic testing in monogenic liver diseases, compiles the results of genome-wide association studies in hepatology and discusses new concepts in the genetics of liver diseases in general.

The gut microbiota is implicated in the etiology of nonalcoholic fatty liver disease (NAFLD) as well as progression to the more severe nonalcoholic steatohepatitis. Evidence supporting this role is mainly from animal models, although data from human studies are also emerging. In this Review, the authors provide an overview of the gut–liver interactions that contribute to the pathogenesis of NAFLD and propose that modification of the gut microbiota by prebiotics or probiotics could be a potentially important therapeutic strategy.

Organ allocation policies have evolved over the past 20 years, particularly with the adoption of mathematical models into clinical practice. There are three possible policies for prioritization for liver transplantation: medical urgency, utility and transplant benefit. The transplant community has still not devised the optimal allocation system for liver transplantation—this Review summarizes the advantages and limitations of the current systems.

Chemokines regulate the migration of immune cells into the liver in response to acute and chronic injuries and also have roles in stellate cell activation, hepatocyte proliferation and angiogenesis. In this Review, the authors describe experimental liver disease models in which chemokines and chemokine receptors have been studied, and highlight agents that are currently under clinical investigation for use in human diseases.

Helicobacter pylorihas an essential role in the development of various gastroduodenal diseases, but only a small proportion of people infected withH. pylori develop these diseases. In this Review, Yoshio Yamaoka discusses current knowledge of the H. pylorivirulence factors CagA, VacA, OipA and DupA. In particular, he considers how these virulence factors contribute to differing geographic gastric cancer disease patterns and to the development of both gastric cancer and duodenal ulcer.

Primary sclerosing cholangitis (PSC) is a progressive inflammatory and fibrosing condition, which can lead to chronic cholestasis and biliary cirrhosis. The pathogenesis of PSC is not clearly understood; therapies that impact disease progression are currently limited—liver transplantation is the only curative treatment modality. This Review provides an update on the current understanding and management of this condition and its associated complications.

Anemia is the most prevalent extraintestinal complication of IBD—it affects both quality of life and ability to work. Although the causes of anemia in IBD are multifactorial, iron deficiency anemia is the most common. In this Review, the authors provide an overview of iron homeostasis in health before discussing diagnostic and therapeutic strategies for iron deficiency anemia in patients with IBD.

The histopathological diagnosis of gastrointestinal cancers is usually unambiguous, but it does have its limitations. In the era of personalized medicine, molecular biomarkers are increasingly being explored, not only as viable diagnostic tools but also for predicting therapeutic response. In this Review, the authors discuss the most common clinically available biomarkers for cancers of the stomach, pancreas and colon, and the most promising molecular biomarkers for esophageal neoplasms.

IBS is a common gastrointestinal condition characterized by abdominal pain associated with altered bowel habits. Limited and judicious use of diagnostic testing is recommended, particularly in patients with typical symptoms without alarm signs and symptoms. Management of IBS is multifaceted and is often driven by illness severity, predominant symptoms and patient and practitioner preferences. Sarah Khan and Lin Chang discuss the current evidence-based recommendations for the diagnosis and management of IBS.

Tuberculosis is one of the most important infectious diseases worldwide. Hepatotoxic effects are a serious problem in patients who are undergoing treatment for tuberculosis, as they can cause morbidity and mortality as well interrupt their therapy and limit the efficacy of the antitubercular regimen. In this Review, Senousy and colleagues discuss the hepatotoxic effects of antituberculosis drugs and the management of these effects.

Bowel cleansing is necessary before a colonoscopy or colonic radiological examination, but the procedure is not without risks. This Review describes the safety issues related to the three major osmotically acting cathartics currently in use for bowel cleansing: sodium-phosphate-based products, polyethylene glycol and electrolyte lavage solutions, and magnesium-citrate-based agents. This Review also includes recommendations for the safe use of these agents in bowel cleansing, and discusses which patients are at risk of serious adverse events.

The etiology of acute biliary pancreatitis is complex and, as outlined in this Review, involves multiple factors including anatomy, genetics, gallstones, bile and pancreatic juice exclusion and ampullary obstruction. In this article, the authors also discuss the importance of establishing a biliary origin in acute pancreatitis and how both serum biochemistry and imaging investigations are vital to confirm a diagnosis of acute biliary pancreatitis.

Hepatic encephalopathy is an important neuropsychiatric complication of liver disease that in severe cases can lead to coma and death. This Review describes the pathogenesis of hepatic encephalopathy including the role of ammonia, inflammation, neurosteroids and manganese in the development of this disorder. The authors also discuss how best to clinically manage patients with hepatic encephalopathy by highlighting the clinical scales and tests used to grade the disorder and the different treatment strategies available.

The use of probiotics is increasing in popularity for both the prevention and treatment of a variety of diseases; however, the specific immune and physiological effects of probiotics in health and disease have not been fully elucidated. This Review considers recent advances in clinical trials of probiotics for intestinal disorders. An overview ofin vitro and in vivoresearch related to potential mechanisms of action of various probiotic formulations is also considered.

Chronic infection with HCV is a major cause of liver-related death worldwide and can be treated with interferon α therapy. This Review focuses on pegylated interferons and will discuss the mechanisms of action, structure, and pharmacokinetics of two different pegylated interferons—PEG-IFN-α2a and PEG-IFN-α2b. Alessio Aghemo and colleagues analyze all available data on these two pegylated interferons and discuss and directly compare the efficacy and safety of these drugs.

Hepatocellular carcinoma is a global health problem, although developing countries are disproportionally affected. About three-quarters of hepatocellular carcinomas are attributed to chronic HBV and HCV infections. This Review provides an overview of the global variation in hepatocellular carcinoma incidence and etiology, as well as the prevention, screening, diagnosis and treatment of this cancer.