Small Intestinal Lesions Resembling Graft Versus Host Disease Changes similar to those found in GVHD sometimes occur in immunosuppressed or immunodeficient patients, without transplants or transfusions. The lesion affects any…
Immunodeficiency Diseases Patients with immunodeficiency syndromes often present with chronic diarrhea, malabsorption, and other intestinal abnormalities, as well as with the effects of the immunodeficiency, particularly infections. The immunodeficiency syndromes…
Graft Versus Host Disease GVHD is an immunologic disorder that results in severe gastrointestinal damage. It represents the response of immunocompetent donor cells to the histocompatibility antigens of the recipient….
Systemic Mastocytosis Systemic mastocytosis is characterized by mast cell proliferation in skin, bones, lymph nodes, and parenchymal organs. Patients usually present with classic dermatologic findings of urticaria pigmentosa. Typical symptoms…
Nutritional Disorders Severe nutritional deficiency can produce marked small intestinal abnormalities. The classic example is kwashiorkor. Malnutrition of this severity seldom occurs in developed countries, but less severe forms may…
Eosinophilic Diseases Food Allergies Up to 45% of the population report adverse reactions to food (572). Various enteric antigens play a role in the pathogenesis of conditions loosely termed food…
Granulomatous and Histiocytic Inflammatory Conditions Small intestinal granulomas form in many disorders (Table 6.15). The nature of the granulomas varies significantly from small macrophage collections that may or may not…
Interpretation of Ileal Biopsies Ileal biopsies are commonly taken when patients undergo colonoscopy. As a result, pathologists often have the opportunity to examine changes that may be present in the…
The Neoplastic Stomach Gastric neoplasms constitute a heterogeneous group of tumors; most are adenocarcinomas. Less common gastric cancers, such as lymphomas, neuroendocrine tumors, and stromal tumors, are discussed in Chapters…
Lipid Malabsorption The three major forms of lipid malabsorption are abetalipoproteinemia, familial hypobetalipoproteinemia (565), and diabetes. Several other related syndromes result in lipid accumulations in enterocytes producing histologic patterns indistinguishable…
