Review Articles

The pathogenesis of gastroparesis is complicated and poorly understood: this lack of understanding has impeded the development of effective therapies for gastroparesis. In this Review, the authors examine the data available on the pathogenesis of gastroparesis, discussing both animal and human studies, and the role of nerves, interstitial cells of Cajal and smooth muscle.

Nutritional support is an established and routine part of patient management. Conventionally, enteral nutrition is preferred to parenteral nutrition, because studies have indicated that enteral nutrition causes fewer complications. In this Review, the author critically analyzes the available data that compare these administration routes, and suggests that the effect of hyperglycemia, energy intake and obesity are perhaps more important than the route of nutrition in determining outcome.

The authors of this Review discuss the increased risk of morbidity and mortality associated with surgery in patients with underlying liver disease, and describe the essential role that preoperative assessment has in these patients. The nature and severity of the underlying liver disease and the type of surgery being undertaken are all considered and guidelines for preoperative assessment provided.

Although the introduction of parenteral nutrition revolutionized the care of premature babies, long-term parenteral nutrition incurs the risk of life-threatening hepatic complications. The authors of this Review discuss the fundamentals of parenteral nutrition associated cholestasis, animal models of the disease, transporters crucial for bile acid homeostasis, and the molecular pathogenesis of this life-threatening condition.

In the past decade, there have been significant advances in the three techniques classically used for liver imaging—ultrasonography, CT and MRI. In this Review, the authors highlight the advances in these techniques that apply to the assessment of focal and diffuse liver disease, including the development of hardware, software, processing algorithms, and procedural innovations.

The authors of this Review discuss current indications for treatment in patients with autoimmune hepatitis, conventional management regimens, therapeutic end points and treatment outcomes. Factors that influence the treatment response, empiric salvage therapies, and promising pharmacological and molecular interventions are also considered.

MRI, and magnetic resonance cholangiopancreatography in particular, is completely noninvasive and allows imaging of the pancreas, as well as the biliary and pancreatic ducts. Technical advances, including the administration of secretin, have improved the quality of the pancreas and pancreatic duct images obtained. The authors of this Review assess the current status of MRI for the evaluation of benign pancreatic disease.

In this Review, the authors examine the most recent clinical evidence for the use of sulfasalazine and mesalazine for the treatment of ulcerative colitis and Crohn's disease. Evidence for the role of mesalazine as a chemoprophylactic agent that protects against the development of colorectal cancer is also discussed.

Bariatric surgery is an effective long-term treatment for morbid obesity. This Review discusses the indications for bariatric surgery and the early and late complications associated with the two most commonly performed bariatric procedures–laparoscopic gastric bypass and laparoscopic adjustable silicone gastric banding. Laparoscopic biliopancreatic diversion and laparoscopic sleeve gastrectomy are also briefly discussed.

It has been suggested that genetic factors are likely to have a major role in the manifestation of functional gastrointestinal disorders. In this Review, the authors consider the evidence available for such a role. They discuss the results of family and twin studies and studies of individual genes thought to be involved in the manifestation of functional gastrointestinal disorders.

Severe ulcerative colitis is considered a medical emergency, the management of which requires close collaboration between gastroenterologists and surgeons. The authors of this Review discuss the identification of prognostic factors and intensive medical treatment for both uncomplicated and complicated ulcerative colitis, as well as the timing of surgery.

The efficacy of biologic therapies is proven and their use is growing worldwide; however, there is concern about their long-term safety, including the risk of developing cancer. In this Review, data available on the association of anti-tumor necrosis factor therapies and the anti-α4 integrin monoclonal antibody natalizumab with cancer in patients with IBD are discussed.

Dyspepsia is remarkably common. Of those individuals with dyspepsia who present for care, perhaps 10% are referred because their symptoms remain refractory and troublesome. Many gastroenterologists seem to feel somewhat at a loss in this situation; however, there are sensible management options to consider. This Review considers the testing and treatment alternatives, and discusses what can be done for the difficult-to treat dyspeptic patient.

Chronic consumption of alcohol can cause a spectrum of liver abnormalities, ranging from simple steatosis to steatohepatitis, cirrhosis and hepatocellular carcinoma. Alcoholic liver disease is still the most common cause of liver cirrhosis in the Western world. This Review focuses on the current management of patients with alcoholic liver disease, with emphasis on alcoholic steatohepatitis and cirrhosis.

The main physiologic function of albumin is to maintain colloid osmotic pressure. The recognition of many other physiologic functions, however, means that the clinical application of albumin has expanded. This Review discusses the physiologic actions of albumin, the clinical settings in which albumin has been used in patients with cirrhosis, and the potential benefits and pitfalls associated with the use of albumin.

In this Review, the authors consider the most common severe complication of endoscopic retrograde cholangiopancreatography (ERCP)—post-ERCP pancreatitis—for which there is no definitive means of prevention. The risk factors for post-ERCP pancreatitis and pharmacologic and procedural ways of reducing its incidence are discussed, including proper patient selection, minimally traumatic cannulation techniques and pancreatic duct stenting.

Vitamin D deficiency is common in patients with cirrhosis and is associated with bone density changes. It is generally recommended that patients with cirrhosis and low bone density receive calcium and vitamin D supplementation, despite a lack of evidence for a role of vitamin D in the pathogenesis or treatment of osteoporosis in cirrhotic patients. This Review revisits the controversy surrounding the role of vitamin D in hepatic bone disease and discusses vitamin D therapy in this setting.

In the US, up to 30% of colon cancers exhibit familial clustering and 3–5% are associated with high-risk, inherited colon cancer syndromes. The authors of this Review discuss the clinical presentation and genetics of the major inherited colon cancer syndromes. Particular attention is paid to genetic testing, including when it is indicated, methods used and potential pitfalls. The role of the genetic counselor is also explored.

This Review considers the bacterial virulence factors and host inflammatory responses involved in the development of gastric cancer afterHelicobacter pylori infection, as well as the signaling pathways affected and possible molecular targets for intervention. The effect of H. pylori eradication and the modification of environmental conditions on the progression of the gastric carcinogenic process triggered by H. pyloriare also discussed.

Advances in our understanding of the molecular events underlying the activation of the immune system have led to the development of a new generation of small molecules with immunosuppressive properties and that serve as immunomodulators. In this Review, the authors report on the progress that has been made in the development of small molecules in the field of gastroenterology.