Review Articles in 2015

Mathematical modelling of the viral kinetics of hepatitis C infection can help inform clinicians of the optimal treatment regimens to achieve a sustained virologic response. In this Review, Perelson and Guedj describe the mathematical models and concepts used to understand hepatitis C infection, its response to antiviral treatment and whether HCV RNA is a reliable biomarker of viral kinetics.

Individuals are increasingly self-reporting gluten sensitivity and placing themselves on a gluten-free diet without diagnosis of coeliac disease or IgE-mediated allergy. This new clinical entity has been termed noncoeliac gluten sensitivity (NCGS). In this Review, the authors provide an overview of NCGS, including immunopathogenesis, clinical features, diagnosis and management, as well as the controversies associated with this condition.

Secretory diarrhoeas are a major cause of mortality and morbidity globally, especially in vulnerable populations such as children and the elderly. Diarrhoea has many environmental causes such as infection with bacteria or viruses, but it can also be a result of genetic defects. In this Review the authors describe the pathogenic mechanisms of secretory diarrhoea and discuss the available therapies and experimental therapies that are being developed.

Gluten-related disorders are increasingly being diagnosed in children. In this Review, Vriezinga and colleagues provide an overview of the most common gluten-related disorders in children: coeliac disease, wheat allergy and noncoeliac gluten sensitivity. Pathogenesis, diagnosis and management of each condition are described.

Emerging evidence indicates that the gut microbiota might have a role in the development of coeliac disease. In this Review, Verdu and colleagues describe how alterations in the composition and function of the gut microbiota might influence coeliac disease pathogenesis, presenting the latest data from human and experimental studies.

In liver diseases, inflammasome activation is a major contributor to hepatocyte damage, immune cell activation and amplification of inflammation. This Review provides a detailed account of the different types of inflammasomes that are involved, their activation and biological functions in the context of liver injury and disease progression.

Peroral endoscopic myotomy (POEM) is a novel treatment for achalasia and other spastic oesophageal motility disorders. Although technically demanding, this technique compares favourably with other therapeutic approaches such as laparoscopic Heller myotomy and pneumatic dilation. In this Review the authors describe the technique, the indications and contraindications, safety and efficacy of POEM.

Biliary atresia is a severe cholangiopathy with a poorly defined pathogenesis and treatment strategy that leads to end-stage cirrhosis in most children. The authors of this Review bring together the most up-to-date understanding of the pathogenesis of biliary atresia, how environmental and genetic factors create various clinical phenotypes and provide insights into future clinical trial design.

Eosinophilic oesophagitis (EoE) is a chronic, immune or antigen-mediated disease. Distinguishing GERD from EoE can be challenging. Controversy exists regarding the clinical interpretation of PPI-responsive oesophageal eosinophilia. This Review describes the current understanding on the complex interplay between GERD and EoE.

Colorectal cancer (CRC) arises from precursor lesions that, contrary to a long-standing belief, are not always adenomas. In particular, the serrated neoplasia pathway is attracting more and more attention as an alternative route to CRC development. This Review provides a current perspective on the serrated neoplasia pathway, combining detailed descriptions of its characteristics and biological mechanisms with clinical observations.

Neural pathways regulate key functions of the gastrointestinal tract, including motility and inflammation. Here, the authors discuss how neural reflex pathways regulate intestinal inflammation, providing insights into the basic underlying mechanisms and the therapeutic potential of interventions that manipulate this system.

A novel family of innate lymphocytes called innate lymphoid cells (ILCs) have been found to accumulate in mucosal tissue and produce cytokines relevant to IBD. This Review describes the subsets of ILCs, how they are involved in IBD pathogenesis and ways in which they reveal new therapeutic targets for IBD treatment.

Interferon-free therapies have widely increased the treatment options for patients with chronic hepatitis C, especially individuals who were deemed 'difficult-to-treat', including those with advanced cirrhosis, end stage renal failure or undergoing liver transplantation. In this Review, Peter Ferenci discusses the best therapeutic options for these 'difficult-to-treat' patients in light of new and on-going trials in this field.

This Review highlightsthe progress that is being made in understanding the pathophysiology, prevalence and potential complications of both oropharyngeal dysphagia and oesophageal dysphagia, particularly in association with impaired physiology. The authors discuss the advances that are paving the way for a transdisciplinary field of deglutology.

Patients with oesophageal dysphagia caused by oesophageal motility disorders can be categorized according to the Chicago Classification.This Review provides an overview of the literature concerning treatment options for patients with dysphagia associated with achalasia, hypercontractile disorders and hypocontractility disorders of the oesophagus.

HCV mixed infection and reinfection occur commonly in people who inject drugs (PWID). The authors review the epidemiology, natural history and methods used to detect mixed HCV infection in PWID. The potential effect of mixed infection and reinfection on treatment outcomes is discussed, as well as how future studies should be designed in the era of direct acting antiviral treatment of HCV.

Congenital diarrhoeal disorders (CDDs) represent an evolving web of rare chronic enteropathies, with a typical onset early in life. The number of well-characterized disorders attributed to CDDs has gradually increased over the past few years and this Review highlights new CDD entities and advances understanding of functionally related genes that are opening new diagnostic and therapeutic perspectives.

Alcoholic liver disease is characterized by a complex spectrum of histological lesions, ranging from steatosis to cirrhosis. This Review discusses the main pathways associated with the progression of liver disease, as well as potential therapeutic strategies targeting these pathways. The need to adapt the design of future studies to the histological lesions of the disease is also highlighted.

The use of nanoscale systems could result in considerable improvements in health care. For example, nanomedicines can be delivered directly to the site of action, thereby reducing the incidence of adverse effects. This Review will discuss the diverse nanomaterials currently available and the first specific uses for select gastroenterological and hepatological pathologies.

The incidence and prevalence of IBD is changing, in both established and emerging populations. Here, the epidemiological trends of IBD are described, as are the risk factors (such as genetics, microbiota and lifestyle) that might contribute to disease development. How these risk factors, particularly the environmental ones, can be modified as a means of intervention for disease management are also discussed.