Seminars in gastrointestinal disease最新文献

Cholestatic jaundice defined as conjugated hyperbilirubinemia is a typical feature of neonatal liver disease. Biliary atresia is the most common disorder producing cholestasis during the first 2 months of life. Syndromic and non-syndromic paucity of the intralobular bile ducts and choledochal cysts can also present with cholestasis during early life. Liver dysfunction from obstruction of the biliary tree must be differentiated from numerous disorders affecting hepatocytes such as congenital infection and inborn errors of metabolism. Early recognition and a stepwise diagnostic evaluation of the cholestatic infant are essential in successfully treating many metabolic and infectious liver diseases of the infant as well as surgically relieving obstruction in patients with biliary atresia.

Acute acalculous cholecystitis is characterized by acute inflammation of the gallbladder in the absence of stones, usually occurring in elderly and critically ill patients with atherosclerosis, recent surgery or trauma, or hemodynamic instability. Patients may present with only unexplained fever, leukocytosis, and hyperamylasemia without right upper quadrant tenderness. If untreated, rapid progression to gangrene and perforation occurs. Surgical cholecystectomy and cholecystostomy provide the most definitive treatment although recent studies indicate success with percutaneous or endoscopic cholecystostomy. Cholesterolosis and adenomyomatosis of the gallbladder are usually clinically silent and incidental findings at the time of cholecystectomy. Cholesterolosis is characterized by mucosal villous hyperplasia with excessive accumulation of cholesterol esters within epithelial macrophages. Usually clinically silent, the condition rarely is associated with biliary symptoms or idiopathic pancreatitis and cannot reliably be detected by ultrasonography. Adenomyomatosis describes an acquired, hyperplastic lesion of the gallbladder characterized by excessive proliferation of surface epithelium with invaginations into a thickened muscularis propria. Ultrasonography may reveal a thickened gallbladder wall with intramural diverticula. Adenomyomatosis may portend a higher risk of gallbladder malignancy. Most cases of cholesterolosis and adenomyomatosis identified by imaging require no specific treatment. Gallbladder polyps include all mucosal projections into the gallbladder lumen and include cholesterol polyps, adenomyomas, inflammatory polyps, adenomas, and other miscellaneous polyps. Most polyps are nonneoplastic and rarely cause symptoms. Cholecystectomy is advocated for polyps greater than 10 mm in size because of increased risk of adenomatous or carcinomatous features.

Therapeutic biliary and pancreatic endoscopy has evolved over the last 30 years to a level where it represents the primarily mode of therapy for many frequently encountered diseases of the bile ducts liver and pancreas. The complication rates are expected to be low and the expectations of our colleagues are high. The endoscopist is expected to understand the origin and natural history of these diseases and the consequences of the various management options. The training of the endoscopist has taken on a very formal character, as has the emphasis on competency and quality improvement. The appearance of minimally invasive surgery and advanced imaging does not represent a threat to the biliary endoscopist but rather is complimentary and assists us so that unnecessary potentially morbid procedures are not done unnecessarily. The appearance of a new specialty: the minimally invasive biliary interventionalist, who would receive training by gastroenterologists, interventional radiologist and biliary-pancreatic surgeons, is the logical next step!

Muscle fibers in the biliary tree, and therefore the potential for dysmotility, are located in the gallbladder and the sphincter of Oddi. Dysmotility at either site is a potential cause of biliary pain in the absence of stones, although significant controversy persists. Diminished gallbladder emptying measured by biliary scintigraphy is an indication for cholecystectomy, although studies are contradictory regarding clinical benefit. It is likely that careful selection of patients for cholescintigraphic testing, many of whom have had missed stones or sludge, will identify patients who benefit from cholecystectomy. However, given the increased incidence of gallbladder stasis in functional gastrointestinal disorders, wide use of this study in patients with abdominal symptoms leads to a frequent failure to respond to cholecystectomy. Sphincter of Oddi dysfunction (SOD) has been best studied in patients with biliary type pain who have had prior cholecystectomy. Much less understood is the association of SOD with idiopathic recurrent acute pancreatitis and chronic pancreatitis. The least-studied clinical association for SOD is in patients with biliary pain and intact gallbladders. Elevated basal sphincter of Oddi pressure is predictive of clinical response to sphincterotomy in patients with postcholecystectomy pain in two randomized sham-controlled studies. However, patients with suspected SOD have the highest complication rate from endoscopic retrograde cholangiogram and sphincterotomy, and, therefore, careful patient selection is mandatory.

Neoplasms arising in the gallbladder, bile ducts, and ampulla of Vater pose a significant clinical challenge. Although benign neoplasms may be encountered, the majority of these tumors are malignant. There are a number of similarities among tumors at these sites including their clinical presentation which may include biliary obstruction. Furthermore, these tumors are often asymptomatic early in their course and frequently present at an advanced stage of disease, precluding potentially curative resection. This article focuses on the diagnosis, staging, and operative management of gallbladder, bile duct, and ampullary tumors, with a specific focus on malignant disease.

Gallstone disease is one of the most common disorders of the gastrointestinal tract, and more cholecystectomies are performed each year in the United States than any other elective abdominal operation. As such, clinicians need a fundamental knowledge of gallstone disease and the common complications that are associated with this disease. Overall, the prevalence of gallstones in the United States is approximately 10% to 15%, of which, approximately 80% are without symptoms. Symptoms will occur in approximately 20% of those with gallstones, and this subgroup is at the highest risk for developing serious complications from their gallstone disease. These complications can range from simple recurrent biliary colic to severe, life-threatening ascending cholangitis and/or pancreatitis. This review will outline the basis for gallstone formation, the underlying mechanisms that result in gallstone-induced symptoms and a rational approach to individuals who present with symptoms consistent with gallstone disease. Current diagnostic and treatment modalities will be discussed, with a particular emphasis on acute cholecystitis and acute biliary pancreatitis.

Primary sclerosing cholangitis (PSC) is an idiopathic, chronic cholestatic liver disease of uncertain etiopathogenesis commonly associated with inflammatory bowel disease (IBD) and is characterized by patchy inflammation of the biliary tree progressing to fibrosis and strictures. The natural history of PSC is highly variable but characteristically follows a progressive clinical course leading to biliary tree strictures, cholestasis, and choledocholithiasis. The course of the disease may be complicated by cholangitis, secondary biliary cirrhosis, liver failure, and cholangiocarcinoma. The diagnosis of PSC is based on typical cholangiographic findings, supported by nonspecific clinical signs and symptoms, cholestatic liver biochemical tests, and liver biopsy. Uncommon and usually clinically obvious secondary causes of sclerosing cholangitis are excluded before establishing the diagnosis of PSC. Therapeutic approaches that show promise include endoscopic therapy and ursodeoxycholic acid. The only accepted therapy for end-stage PSC that can improve long-term outcome is liver transplantation. The diagnosis of cholangiocarcinoma--often difficult and elusive--usually precludes liver transplantation because its prognosis is very poor.

Symptomatic gallstone disease is one of the most common illnesses requiring surgical therapy. In the United States, an estimated 700,000 people will undergo cholecystectomy for gallstones this year. The average patient has an uncomplicated postoperative course and is satisfied with the results of treatment. However, complications do occur and the prudent clinician should have a clear understanding of their causes, prevention, recognition, and the management strategies for their successful resolution. These issues are reviewed in the this article.

The incidence of esophageal adenocarcinoma has risen rapidly over the past 3 decades. This increase had been most dramatic among white men. It has supplanted squamous cell carcinoma as the predominant histologic type of esophageal cancer in the United States. The reasons underlying this phenomenon are not readily apparent. Improvements in diagnostic techniques and changes in cancer classification may explain some of the rise in reported incidence rates, but detection bias and misclassification bias do not appear adequate to explain the increase entirely. Risk factors for esophageal adenocarcinoma are reviewed, with particular emphasis on their role in underlying the rising cancer incidence. The etiologic factors most likely to explain the current epidemic of esophageal adenocarcinoma are the parallel epidemic of obesity, rising use of lower esophageal sphincter-relaxing medications, decreasing Helicobacter pylori infection, changes in the Western diet, and distant smoking habits.

Barrett's esophagus is most often seen in white men with chronic heartburn who are generally older than 50 years of age. The prevalence of Barrett's esophagus is 10% to 15% in patients who are undergoing endosocopy for gastroesophageal reflux disease and 1% to 2% in asymptomatic American adults. Barrett's esophagus represents metaplastic columnar tissue with specialized intestinal metaplasia, and this condition carries an increased risk of esophageal adenocarcinoma. Patients with Barrett's esophagus have a risk of esophageal adenocarcinoma 30 to 60 times that of the general population with an incidence rate of over 100 times that of the general population. Esophageal adenocarcinoma has increased dramatically over the past few decades with specialized intestinal metaplasia being the most important risk factor for the development of dysplasia and cancer. Barrett's esophagus develops in the presence of persistent gastroesophageal reflux, which is an independent risk factor for adenocarcinoma. Other risk factors for adenocarcinoma in patients with Barrett's esophagus include length of Barrett's epithelium, low-grade dysplasia, and high-grade dysplasia. New data concerning the pathophysiology and biology of Barrett's epithelium may provide answers to prevent or treat esophageal cancer. This article briefly reviews Barrett's esophagus and focuses on the risk factors associated with its progression to adenocarcinoma.