Yersinia Laura W. Lamps, MD Key Facts Etiology/Pathogenesis Common food- and water-born gastrointestinal infection Image Findings May mimic acute appendicitis or Crohn disease May show nonspecific features of enterocolic inflammation…

Pouchitis Joel K. Greenson, MD Key Facts Clinical Issues Acute pouchitis may be due to bacterial overgrowth and respond to antibiotics Chronic relapsing pouchitis that does not respond to antibiotics…

Autoimmune Enterocolitis Joel K. Greenson, MD Key Facts Terminology Rare form of intractable diarrhea secondary to enteropathy associated with autoantibodies Clinical Issues Anti-enterocyte antibodies: Indirect immunofluorescence using patients’ serum against…

Primary Lymphangiectasia Joel K. Greenson, MD Key Facts Clinical Issues Presentation is often within 1st 3 years of life, although some patients present later Decreased serum albumin, protein, and gammaglobulins…

Necrotizing Enterocolitis Joel K. Greenson, MD Key Facts Etiology/Pathogenesis Hyperosmolar feedings increase risk of disease Bacterial colonization also seems to play a role Clinical Issues Death secondary to sepsis from…

Large Cell Lymphoma Scott R. Owens, MD Key Facts Terminology “Large”: Cells with nucleus ≥ macrophage nucleus or > 2x normal lymphocyte nucleus Etiology/Pathogenesis Secondary DLBCL arises from preexisting low-grade…

Malt Lymphoma Scott R. Owens, MD Key Facts Etiology/Pathogenesis Most gastric MALT lymphomas associated with gastritis caused by Helicobacter pylori infection Clinical Issues 85% of all GI MALT lymphomas in…

Carcinoid Tumor, Stomach Gregory Y. Lauwers, MD Key Facts Clinical Issues Gastric carcinoids represent 5% of all gastrointestinal carcinoids Most carcinoids (type 1, 2, and 4) are fundic Type 3…

Adenoma, Stomach Gregory Y. Lauwers, MD Key Facts Terminology Polypoid gastric dysplasia Unequivocal, noninvasive, polypoid, dysplastic gastric epithelium Etiology/Pathogenesis Secondary to Helicobacter pylori gastritis with intestinal metaplasia Fundic gland polyps…

Fundic Gland Polyp Gregory Y. Lauwers, MD Key Facts Terminology Benign cystic and polypoid transformation of oxyntic mucosa Etiology/Pathogenesis Sporadic Familial adenomatous polyposis Proton pump inhibitor Zollinger-Ellison syndrome Clinical Issues…