Review Articles in 2011

Numerous diseases that involve the gastrointestinal tract reveal the presence of granulomas on histological analysis. In this Review, the pathogenesis and etiologies of granulomas of the gastrointestinal tract and liver are discussed, as are the available diagnostic tools to help differentiate their various underlying etiologies. The role of granulomas in harboring latent tuberculosis is also discussed, as are the effects of tumor necrosis factor antagonists and interferon-α on granuloma development.

Cholangiocarcinoma is the most common primary malignancy of the biliary tract. Currently, this cancer is classified into the following types according to its anatomic location along the biliary tree: intrahepatic, perihilar or distal extrahepatic. These cholangiocarcinoma types differ in their biological behavior and management. Blechacz et al. discuss the emerging diagnostic criteria as well as the different staging systems for cholangiocarcinoma, and provide a critical appraisal regarding these advances in biliary tract malignancies.

Constipation is a common functional gastrointestinal disorder in children, characterized by withholding of stools, infrequent and painful passage of hard stools, and episodes of fecal incontinence. In this Review, the authors describe the prevalence and pathophysiology of childhood constipation as well as discuss the latest available knowledge on the diagnosis, treatment and follow-up of these pediatric patients.

Gastroparesis is a prevalent condition that produces symptoms of delayed gastric emptying in the absence of physical blockage. Over the past 5 years, considerable advances have been made in understanding gastroparesis, and the number of treatment options has expanded. William Hasler thus provides a timely Review of the pathogenesis, diagnosis and management of this condition.

The aim of sedation in endoscopic procedures is to increase the patient's comfort and to improve endoscopic performance, especially in therapeutic procedures. This Review focuses on standard and new methods of procedural sedation and their complications. It provides an approach to choose the best sedation strategy for each patient, tailored according to the clinical risk assessment and the anxiety level of the patient, as well as to the type of planned endoscopic procedure.

Bariatric surgery is emerging as an important and broadly available treatment for people with severe and complex obesity that has not responded adequately to other therapy. Gastroenterologists need to be aware of the risks and benefits of current and emerging procedures as they are likely to be increasingly involved in the integrated care of patients. This Review summarizes the evidence for the safety, efficacy and cost-effectiveness of bariatric surgery, as well as discussing mechanisms of action and future directions for surgery.

The early identification of patients with ulcerative colitis who have an increased risk of colorectal cancer would be useful for clinicians. In this Review, the authors discuss the most promising preneoplastic biomarkers, including p53 mutations, chromosomal instability and senescence, in ulcerative colitis. They also present the available knowledge regarding the pathogenesis of ulcerative colitis-associated colorectal cancer.

Despite some advances, the search for effective treatment modalities for advanced gastric and gastro-esophageal junction cancer (GEJC) is far from over. However, using biologic agents to target key molecular pathways, such as those regulated by human epidermal growth factor receptor (HER) family members, may be an effective approach. This Review briefly describes HER biology, summarizes available data regarding the clinical activity of anti-HER agents and their use in gastric cancer and GEJC, and provides insight into treatment personalization strategies.

Aspirin is one of the most prescribed drugs worldwide, as it can prevent cardiovascular morbidity and mortality. However, aspirin can cause gastrointestinal complications. In this Review, Angel Lanas and Carlos Sostres discuss the gastrointestinal effects of aspirin and suggest that physicians need to consider the advantages and risks for individual patients to maximize the benefits of aspirin.

Obesity is associated with an increased risk of the intimately related esophageal disorders GERD, Barrett esophagus and esophageal adenocarcinoma. In this Review, Jesper Lagergren evaluates the effect of BMI and body fat distribution on the risk of these esophageal conditions and discusses the potential underlying mechanisms.

A subset of patients with IBS have visceral hypersensitivity and/or somatic hypersensitivity. This Review discusses the mechanisms that could underlie hypersensitivity in these patients, including impulse input from the colon in the induction and maintenance of hypersensitivity, increased intestinal permeability and alterations in microRNA expression.

Exocrine pancreatic disease is thought to be uncommon; however, several conditions are associated with exocrine pancreatic insufficiency and it perhaps occurs more frequently than is conventionally expected. A reliable, patient-friendly, cheap and easy to use test for exocrine pancreatic disease is yet to be established. This Review examines the role of fecal-elastase 1 testing in detecting exocrine pancreatic insufficiency in a number of conditions and determines the value of pancreatic enzyme supplementation in these settings.

Managing patients with decompensated cirrhosis related to hepatitis B or hepatitis C is challenging, and liver transplantation is often seen as the only viable option. However, the authors of this Review discuss other treatment options that are available. Treatment should focus on controlling the complications of cirrhosis, surveillance for hepatocellular carcinoma and, if applicable, preparation for liver transplantation.

Autoimmune hepatitis (AIH) is a progressive inflammatory disorder that mainly affects females. It is a relatively rare but devastating disease that progresses rapidly unless immunosuppressive treatment is started promptly. The Review provides an overview of the epidemiology, diagnosis, pathogenesis and treatment of AIH.

Controversy exists with regard to the optimal treatment for achalasia and whether surveillance for early recognition of late complications is indicated. Providing a critical analysis of hot topics within the field, this Review article is an essential update on all aspects of the diagnosis, treatment and management of this rare primary motility disorder. The authors also discuss current and future developments including the value of exciting new endoscopic, radiologic and surgical treatments.

The incidence ofClostridium difficileinfection (CDI) has increased in the past decade, with greater numbers of patients with refractory and recurrent CDI being seen. In this Review, the authors discuss the role of medical therapy (including antibiotics, immune approaches and fecal microbiota transplant) in the treatment of refractory and recurrent disease as well as that of surgery for refractory CDI.

Over 170 million individuals are chronically infected with HCV. The current standard of care for these patients is 24–48 weeks of PEG-IFN-α and ribavirin; however, many patients do not respond to this treatment. This article summarizes the findings from phase III clinical trials on the introduction of telaprevir and boceprevir to this standard therapy.

Cholangiocarcinomas are often difficult to diagnose, their pathogenesis is poorly understood, and their dismal prognosis has resulted in a nihilistic approach to their management. This Review outlines some of the current challenges, discusses the types of cholangiocarcinoma and offers recommendations for the management of patients with cholangiocarcinomas.

The asymptomatic nature of acute HCV infection and difficulties in identifying and following those at risk of acquiring infection has hampered our knowledge regarding treatment for this condition. This Review highlights current knowledge of the epidemiology, diagnosis, natural history and treatment of acute HCV infection, and includes proposed recommendations for the assessment and treatment of this infection.

Substantial progress had been made in the treatment of hepatitis B in the past decade; many safe and effective drugs are now available. However, these drugs suppress but do not eradicate HBV. In addition, these agents may be associated with drug resistance and adverse effects. Hellan Kwon and Anna Lok address important questions regarding the optimization of treatment in patients with hepatitis B.