Skip to Main Content

++

The main purpose of the gastrointestinal tract is the transport of food and the absorption of nutrients. Many pathologic conditions of the gastrointestinal tract impair either or both of these functions. The gastrointestinal tract, and especially the colon, is a common site of malignancy. The two main symptoms related to pathology of the gastrointestinal tract are abdominal pain and gastrointestinal hemorrhage.

++

The differential diagnosis for abdominal pain can be classified as either acute or chronic, based upon the length of time of the pain (Table 14-1). The four categories of the causes of acute abdominal pain are (1) inflammation, including appendicitis, cholecystitis, pancreatitis, and diverticulitis; (2) perforation; (3) obstruction; and (4) vascular disease, including acute ischemia and ruptured abdominal aortic aneurysm. The five categories of causes of chronic abdominal pain are (1) inflammation, including peptic ulcer disease, esophagitis, inflammatory bowel disease, and chronic pancreatitis; (2) vascular disease, including chronic ischemia; (3) metabolic disease, including porphyria; (4) abdominal wall pain; and (5) functional causes, including irritable bowel syndrome. The most frequent causes of chronic abdominal pain are functional.

++
Table Graphic Jump Location
Table 14-1. Causes of Abdominal Pain
++

The second main symptom of gastrointestinal pathology is bleeding (Table 14-2). The character of the blood can help identify the source: hematemesis (i.e., vomiting of bright red blood), if the source is gastrointestinal, is most likely due to a source proximal to the ligament of Treitz. Melena (i.e., black, tarry stool) is most often due to upper gastrointestinal bleeding. Hematochezia (i.e., bright red blood per rectum) usually indicates a lower gastrointestinal bleed (or very rapid upper gastrointestinal bleed). The differential diagnosis of upper gastrointestinal bleeding includes gastritis, esophageal varices, and peptic ulcer disease (as a result of erosion into a blood vessel). The diagnosis of the source of an upper gastrointestinal bleed is often made by endoscopy. The differential diagnosis of lower gastrointestinal bleeding includes a rapid upper gastrointestinal bleed, diverticulosis, infections (e.g., Salmonella, Shigella), cancer, inflammatory bowel disease, and anal fissures or hemorrhoids. The diagnosis of a lower gastrointestinal bleed is often determined by flexible sigmoidoscopy or colonoscopy.

++
Table Graphic Jump Location
Table 14-2. Causes of Gastrointestinal Bleeding
++

This chapter will discuss pediatric gastrointestinal disorders, pathology of the oral ...

Want remote access to your institution's subscription?

Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessMedicine Full Site: One-Year Subscription

Connect to the full suite of AccessMedicine content and resources including more than 250 examination and procedural videos, patient safety modules, an extensive drug database, Q&A, Case Files, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessMedicine

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.