Term
|
Definition
| organism produces an enterotoxin that causes massive secretion of water and sodium in small intestine and interferes with the ability of the large intestine to absorb water. |
|
|
Term
| general features of Cholera |
|
Definition
| Clinically the patient has profuse watery diarrhea. As a result they experience acute dehydration, hypovolemic shock, and metabolic acidosis. |
|
|
Term
| pathogensis of salmonella |
|
Definition
| Organism tends to involve Peyer patches (diffuse lymphatic nodules located in the terminal ileum). Bacteria invade mucosal surface and elaborate a toxin which causes diarrhea. |
|
|
Term
| general features of salmonella |
|
Definition
| : bloody diarrhea (more frequently involves large bowel) - often caused by salmonella-shigella organisms - "bacillary dysentery." Surface mucosa ulcerated and hemorrhagic |
|
|
Term
| pathogensis of tuberculosis of the bowel |
|
Definition
| can affect the terminal ileum (organism prefers Peyer's patches). Can result in peritoneal adhesions, perforation. |
|
|
Term
| general features of tuberculosis of the bowel |
|
Definition
| Pain, weight loss, night sweats, obstruction, GI bleeding |
|
|
Term
| pathogenesis of Giardiasis |
|
Definition
| flagellated protozoan that prefers the small intestine. Elaborates local irritant that produces diarrhea. |
|
|
Term
| general features of Giardiasis |
|
Definition
| Malabsorptive diarrhea from mucosal injury, Small intestinal biopsy may be normal or show blunting of villi with mixed inflammatory infiltrate |
|
|
Term
| pathogenesis of Strongyloidiasis |
|
Definition
| Infective filariform larvae penetrate skin or buccal mucosa, enter vessels, and reach the lungs, where they undergo some maturation. They pass into the alveoli, travel through the bronchi and trachea, and then enter the gastrointestinal tract (are coughed up and swallowed). The female worm deposits eggs in the crypts of the small intestine. The eggs hatch, producing rhabditiform larvae which are passed in the stool or can transform to filariform larvae in the colon; can penetrate the colonic mucosa, and cause reinfection. |
|
|
Term
| general features of Strongyloidiasis |
|
Definition
| important infection in immunosuppressed. Infection is by soil contaminated with fecal material. |
|
|
Term
| pathogenesis of Cryptosporidiosis |
|
Definition
| extracellular parasite transmitted by fecal-oral route |
|
|
Term
| general features of Cryptosporidiosis |
|
Definition
| Profuse diarrhea and malabsortion that may be life-threatening in immunosuppressed patients |
|
|
Term
| pathogenesis of Schistosomiasis |
|
Definition
| Cercariae can penetrate human skin coming into contact with the infected water. Larvae will penetrate the venules or lymphatics of the dermis, are carried through the bloodstream. Important lesions that develop are caused by the deposition of eggs in the liver, the walls of the bowel and urinary bladder, as well as other tissues. |
|
|
Term
| general features of Schistosomiasis |
|
Definition
| snail as intermediate host |
|
|
Term
| pathogenesis of Entamoebiasis |
|
Definition
| Invades surface of large intestine, causing ulcers. May penetrate vessels, travel to the liver, producing amebic abscesses. |
|
|
Term
| general features of Entamoebiasis |
|
Definition
| protozoan that primarily affects the colon |
|
|
Term
| pathogenesis of pseudomembranous colitis |
|
Definition
| The normally minor Commensal organisms of the bowel, classically Clostridium difficile, are able to proliferate and produce a necrotizing enterotoxin that causes an ulcerative inflammation on the surface of the bowel |
|
|
Term
| general features of pseudomembranous colitis |
|
Definition
| related to administration of broad-spectrum antibiotics |
|
|
Term
|
Definition
| regional enteritis that affects terminal ileum or colon |
|
|
Term
| morphology of Crohn Disease |
|
Definition
| skip lesions, transmural inflammation, noncaseating granulomas, fissures with fistulas and anal involvement |
|
|
Term
| clinical course of Crohn Disease |
|
Definition
| extraitestional complications (arthritis, uveitis), variable and unpredictable presentation, diarrhea, crampy pain and fever, risk of carcinoma is less than with ulcerative colitis |
|
|
Term
| Ulcerative colitis definition |
|
Definition
| - recurrent acute and chronic ulceroinflammatory disorder affecting principally rectum and left colon, but sometimes the entire large bowel. |
|
|
Term
| morphology of Ulcerative colitis |
|
Definition
| nongranulomatous, continuous involvement (no skip lesions), psudopolyps, little fibrosis |
|
|
Term
| clinical course of Ulcerative colitis |
|
Definition
| arthritis, greater risk for carcinoma |
|
|
Term
| similarities between Crohn disease and Ulcerative colitis |
|
Definition
| accompanied by extraitestional complications, like arthritis, both peak incidence at 20-30 |
|
|
Term
| differences between Crohn disease and Ulcerative colitis |
|
Definition
| Crohn is less prevalent, Crohn has a decreased risk of carcinoma, and Crohn has skip lesions, ulcerative colitis has continuous involvement, Crohn has noncaseating granulomas, ulcerative colitis is nongranulomatous, ulcerative colitis is limited to the colon, and Crohn can involve any part of the GI tract |
|
|
Term
incidence of diverticular
disease |
|
Definition
| : rare in persons younger than 30, prevalence approaches 50% in western adult population after age 60, less common in Japan |
|
|
Term
etiology of diverticular
disease |
|
Definition
| low fiber diet, straining at stool with back pressure, increased luminal pressure, exaggerated peristaltic contractions, spasmodic sequestration of bowel segments, reduce stool bulk |
|
|
Term
pathogenesis of diverticular
disease |
|
Definition
| numerous outpunching of the colon, particularly in the rectosigmoid area (outpunching occur between the teniae coli). Developed after conditions of elevated luminal pressure in the sigmoid colon, muscle layer is discontinuous |
|
|
Term
clinical course of diverticular
disease |
|
Definition
| asymptomatic, intermittent cramping, continuous lower abdominal discomfort, constipation and diarrhea. When complicated by fecoliths and inflammation - diverticulitis. "Left sided appendicitis.", perforation, abscess and bleeding |
|
|
Term
| diverticulosis definition |
|
Definition
| condition in which acquired diverticular outpouchings occur on the colonic mucosa and submucosa |
|
|
Term
| diverticulitis definition |
|
Definition
| inflammation of the diverticula |
|
|
Term
|
Definition
| dilated anal and perianal collateral vessels that connect the portal and caval venous systems to relieve elevated venous pressure within the hemorrhoid plexus |
|
|
Term
|
Definition
| : related to low fiber, low residue diet, elevated venous pressure. With dehydration of fecal material in the large intestine a hard stool is formed, making straining at time of defecation necessary. The increased abdominal pressure forces hemorrhoidal veins to become dilated |
|
|
Term
| clinical significance of hemorrhoids |
|
Definition
| Hemorrhoids are also frequently related to pregnancy, especially at the time of delivery |
|
|
Term
| causes of bowel obstruction |
|
Definition
| may be related to some previous abdominal injury such as inflammation, surgery, endometriosis, conditions which all result in formation of adhesions (fibrous scars which contract). Other causes - hernia, intussusception, and volvulus. Constipation and invasion by tumor can also cause obstruction (these affect the large bowel more frequently). |
|
|
Term
| significance of bowel obstruction |
|
Definition
| painful and life threatening |
|
|
Term
| general incidence of tumors of small intestine |
|
Definition
| carcinoma (90-95%), lymphoma (4%), carcinoid (3%) and GIST (2%) |
|
|
Term
| the most common benign tumors of the small intestine |
|
Definition
|
|
Term
| the most common malignant tumors of the small intestine |
|
Definition
|
|
Term
| most common site of development of adenocarcinoma of the small intestine |
|
Definition
| tend to arise around ampulla of Vater (where pancreatic and bile ducts empty into duodenum). |
|
|
Term
| clinical symptoms of adenocarcinoma of the small intestine |
|
Definition
| Presenting signs - jaundice, pancreatitis - due to blockage of ampulla |
|
|
Term
| carcinoid tumor definition |
|
Definition
|
|
Term
| common sites involved by carcinoid tumor |
|
Definition
| Appendix most common site of gut carcinoid; then ileum, stomach and colon |
|
|
Term
| clinical course of carcinoid tumor |
|
Definition
| Once tumor has metastasized to the liver, detoxification is not possible before the serotonin escapes into the circulation and causes the characteristic syndrome of episodic flushing of the skin, intestinal hypermotility (diarrhea, vomiting), bronchoconstrictive attacks resembling asthma, heart failure, edema. |
|
|
Term
|
Definition
| rare, can be non-neoplastic growth or neoplastic (adenoma) |
|
|
Term
| incidence of hyperplastic polyps of the colon |
|
Definition
|
|
Term
| gross features of hyperplastic polyps of the colon |
|
Definition
| left colon, less than 5mm in diameter, smooth, nodular protrusions of the mucosa, on the crests of musical folds, occur singly or in multiples (sigmoid colon and rectum), mature globet cells, absorptive cells, delayed shedding leads to crowding --> serrated surface architecture (hallmark) |
|
|
Term
| clinical significance of hyperplastic polyps of the colon |
|
Definition
| must be distinguished from sessile serrated adenomas, no malignant potential |
|
|
Term
| incidence of adenomatous polyps of the colon |
|
Definition
| most common neoplastic polyp |
|
|
Term
| gross features of adenomatous polyps of the colon |
|
Definition
| presence of epithelial dysplasia, 0.3-10 cm in diameters, pedunculated or sessile, nuclear hypochromasia, elongation, and stratification |
|
|
Term
| clinical significance of adenomatous polyps of the colon |
|
Definition
| give rise to a majority of colorectal adenocarcinomas |
|
|
Term
| relationship of adenomatous polyps of the colon to carcinoma |
|
Definition
| The extent of the neoplasm is the most important prognostic factor in patients with colon carcinoma. Most neoplasms are histologically well-differentiated. The larger the adenomatous growth and the more villous (finger-like) the growth pattern, the greater the chance it has carcinoma in it |
|
|
Term
| relationship of familial polyposis to carcinoma of the colon |
|
Definition
| 100% risk of developing colon carcinoma |
|
|
Term
| incidence of colon carcinoma |
|
Definition
| common, 102,480 new cases in 2013 colon |
|
|
Term
| etiology of colon carcinoma |
|
Definition
| low fiber, high carbohydrate, high fat, decreased Vitamins A,C,E, Iron deficiency anemia in elderly highly worrisome for colorectal carcinoma |
|
|
Term
| pathogenesis of colon carcinoma |
|
Definition
| Carcinoma develops from adenomas through series of mutations leading ultimately to malignant transformation |
|
|
Term
| clinical course of colon carcinoma |
|
Definition
| Symptoms develop insidiously: bleeding, change in stool, pain, weakness, fatigue |
|
|
Term
| Difference in gross morphology between carcinoma of the left colon and carcinoma of the right colon |
|
Definition
| Left sided morphology is annular/endophytic with napkin ring constriction, right sided morphology is polypoid exophytic |
|
|
Term
| difference in symptoms between carcinoma of the left colon and carcinoma of the right colon |
|
Definition
| symptoms of left sided carcinoma bleeding, change in stool and pain or discomfort, symptoms of right sided carcinoma fatigue, weakness and IDA |
|
|
Term
| After a summertime camping trip in the Cascade mountains of Washington state, a 29-year-old man developed a mild watery diarrhea for a week. While on the trip he drank water from the mountain streams. A physical examination showed no abdominal pain or masses. He didn't have a fever. Bowel sounds were present. His stool was negative for occult blood. The diarrhea abated after 3 weeks. His two children are similarly affected by the organism shown in the image. What is this organism? |
|
Definition
|
|
Term
| Which organism is a flagellated protozoan that causes diarrhea and usually infects man as a contaminant of drinking water? |
|
Definition
|
|
Term
| This inflammatory bowel disease (IBD) is characterized by granulomatous inflammation involving all layers of the bowel wall. What is this IBD? |
|
Definition
|
|
Term
| Which term includes all the others? |
|
Definition
| inflammatory bowel disease |
|
|
Term
| In which part of the gastrointestinal tract are neoplastic polyps MOST commonly seen? |
|
Definition
|
|
Term
| A 20-year-old man was healthy but has a family history of colon cancer at a young age. There were no abnormal physical exam findings. He underwent a colonoscopy and similar to the image shown, there were over 200 tubular adenomas ranging in size from 0.2 to 1 cm on gross inspection and microscopic examination of biopsies. Which of the following genetic diseases is he most likely to have? |
|
Definition
| Hereditary non-polyposis colon carcinoma syndrome |
|
|
