Numerous systemic diseases have GI and hepatic manifestations, but only common diseases and those with recent developments will be discussed in this chapter. Involvement can occur via changes in GI/hepatic structure, function, or both and may relate directly to the…
Transplantation of a solid organ is an immunologic mirror of the transplantation of allogeneic hematopoietic cells. Thus solid organs can be rejected by the patient in whom they are placed, whereas allogeneic hematopoietic cells can damage or “reject” the organs…
In 1981, the first cases of what we now recognize as AIDS were described. Subsequently, the world witnessed an explosion of cases typically manifested by opportunistic infections (OIs) such as Pneumocystis jiroveci pneumonia and neoplasms such as Kaposi sarcoma, which…
Neuroendocrine tumors (NET) originate from the diffuse neuroendocrine system discussed in Chapter 4 . Gastroenteropancreatic NETs (GEP-NETs) can originate in the GI tract (GI-NETs, also known as carcinoid tumors) and pancreas (pNETs). GEP-NETs are characterized by a propensity to produce…
GISTs comprise 1% to 3% of all malignant GI tumors; they are the most common mesenchymal tumor of the GI tract. More than 20 years ago, a seminal discovery was made that began elucidating the pathogenesis of most GISTs at…
Lymphomas are solid malignancies of the lymphoid system and are subdivided into Hodgkin and non-Hodgkin lymphomas (NHLs). It was estimated that in 2017 there would be 8260 and 72,240 new diagnoses of Hodgkin and NHL, respectively, in the US. The…
Definition and Normal Physiology Protein-losing gastroenteropathy describes a diverse group of disorders associated with excessive loss of serum proteins into the GI tract. This excess serum protein loss can result in hypoproteinemia and may be manifested by edema, ascites, and…
Eosinophilic GI disorders (EGIDs) are defined by selective eosinophil-rich inflammation along the GI tract in the absence of known causes for eosinophilia (e.g., drug reactions, parasitic infections, malignancy) and in association with GI-related symptoms. EGIDs include a spectrum of conditions,…
Abdominal Abscess An intra-abdominal abscess (IAA) is a localized abdominal infection arising in the background of infectious peritonitis. Primary peritonitis (spontaneous bacterial peritonitis, discussed in Chapter 93 ) is not usually associated with development of abscesses, whereas secondary peritonitis ,…
Gastrointestinal foreign bodies (GIFBs) are composed of food bolus impactions and intentionally and unintentionally ingested or inserted foreign objects. Bezoars are ingested materials (food or other materials) that accumulate in a normal or abnormal stomach. Caustic ingestions present following ingestion…