Current Gastroenterology Reports

Colon polyps are a common finding in pediatrics and can present with rectal bleeding, abdominal pain, or polyp prolapse from the rectum. Histologically classified as hamartomas, these isolated pediatric polyps lack epithelial dysplasia and have no cancer risk. However, when polyps are present in greater numbers, or are associated with a family history of polyps or colon or other cancers, a polyposis or hereditary colorectal cancer syndrome should be considered. Using a casebased format, this article reviews the clinical features and provides updates on the three most common hamartomatous polyp syndromes of childhood: juvenile polyposis syndrome, Peutz-Jeghers syndrome, and the PTEN hamartoma tumor syndrome. Each syndrome has distinctive intestinal and extra-intestinal findings that, when present, can guide genetic counseling and testing. Lifelong cancer surveillance is crucial to disease prevention and the long-term health of these patients and their families.

Acute cholecystitis can develop without gallstones in critically ill or injured patients. However, the development of acute acalculous cholecystitis is not limited to surgical or injured patients, or even to the intensive care unit. Diabetes, malignant disease, abdominal vasculitis, congestive heart failure, cholesterol embolization, and shock or cardiac arrest have been associated with acute acalculous cholecystitis. Children may also be affected, especially after a viral illness. The pathogenesis of acute acalculous cholecystitis is a paradigm of complexity. Ischemia and reperfusion injury, or the effects of eicosanoid proinflammatory mediators, appear to be the central mechanisms, but bile stasis, opioid therapy, positive-pressure ventilation, and total parenteral nutrition have all been implicated. Ultrasound of the gallbladder is the most accurate diagnostic modality in the critically ill patient, with gallbladder wall thickness of 3.5 mm or greater and pericholecystic fluid being the two most reliable criteria. The historical treatment of choice for acute acalculous cholecystitis has been cholecystectomy, but percutaneous cholecystostomy is now the mainstay of therapy, controlling the disease in about 85% of patients. Rapid improvement can be expected when the procedure is performed properly. The mortality rates (historically about 30%) for percutaneous and open cholecystostomy appear to be similar, reflecting the severity of illness, but improved resuscitation and critical care may portend a decreased risk of death. Interval cholecystectomy is usually not indicated after acute acalculous cholecystitis in survivors; if the absence of gallstones is confirmed and the precipitating disorder has been controlled, the cholecystostomy tube can be pulled out after the patient has recovered.

Pancreatic cystic lesions are being increasingly identified with the widespread use of state-of-the-art imaging. These lesions are categorized into a broad range of neoplastic cysts and inflammatory pseudocysts. Identification of a pancreatic cyst requires the clinician to focus on the main clinical challenge of the benign or malignant nature of the cyst. Neoplastic cysts range the spectrum from benign, to premalignant, to frank malignancy. The management of these lesions is difficult, and the decision to resect or observe a lesion is hampered by limitations in current imaging and tissue sampling techniques that prevent the accurate characterization of all lesions. This article reviews current guidelines for the evaluation of pancreatic cystic lesions, underscores the challenges posed by these lesions, and discusses current and future studies that will aid in patient management.

Cancer chemoprevention is defined as the pharmacologic intervention, by drugs or nutrient-components, with the process of carcinogenesis, in order to prevent the development of invasive malignant neoplasms [1]. This preventive attempt is particularly challenging in cancer types, which have a long subclinical developmental phase, because of their low cellular proliferation rate and their slow pre-clinical evolution, until they become clinically detectable and therapeutically as well as prognostically relevant. Therefore, only certain specific cancer types are presently in the focus of clinical chemoprevention. Among the GI tract cancer, colorectal (CRC) as well as esophageal cancer have raised the most attention over the past decades, as they both share a long precancerous stage (the adenoma in CRC and Barrett's esophagus in the case of esophageal adenocarcinoma) which provides a window of opportunity to intervene and prevent development of cancer. In this review, we will focus on both CRC as well as esophageal adenocarcinoma (EAC).

Acute pancreatitis is a common cause for hospitalization that carries a substantial burden of disease in the United States and worldwide. Recent reports have encompassed a wide array of topics including new insights into the acinar cell pH microenvironment, signal pathways for acinar cell fate, and the innate immune response. Clinical researchers have reported new methods to assess disease severity, innovative techniques for management of local complications, the importance of early recognition of pancreatic or extrapancreatic infection, and prevention of disease recurrence. Recent data also suggest that specialized centers may be of benefit for the management of severe acute pancreatitis. This review summarizes a number of recent advances in basic and clinical science with an emphasis on findings that are relevant to clinicians who manage patients with acute pancreatitis.

Herpes simplex virus (HSV) infection is well known as a sexually transmitted disease. However, relatively little has been published concerning the presentations and treatment of HSV infection within the gastrointestinal tract, where HSV most commonly affects the esophagus in both immunocompromised and immunocompetent patients. HSV proctitis is not uncommon and occurs primarily in males having sex with males. In patients with normal immune systems, gastrointestinal HSV infections are generally self-limited and rarely require antiviral therapy. Treatment of infection is suggested for immunocompromised patients, though no large randomized controlled trials have been performed. This article reviews the manifestations of HSV infection within the luminal gastrointestinal tract and options for diagnosis and treatment.

Autoimmune pancreatitis (AIP) is the pancreatic manifestation of a systemic fibroinflammatory disease (IgG4-related systemic disease) in which affected organs demonstrate dense lymphoplasmacytic infiltration with abundant IgG4-positive cells. The diagnosis of AIP and its differentiation from pancreatic cancer, its main differential diagnosis, remains a clinical challenge. The five cardinal features of AIP are characteristic histology, imaging, and serology; other organ involvement; and response to steroid therapy. Recent advances in our understanding of these features have resulted in enhanced recognition and diagnosis of this benign disease. This in turn has resulted in the avoidance of unnecessary surgical procedures for suspected malignancy. This article reviews recent updates in the diagnosis and treatment of autoimmune pancreatitis.