CC Jan 2016 H. pylori and gastric cancer

echoecho's version from 2016-02-01 13:40


Question Answer
Describe the H. pylori bacterium?1) gram negative 2) spiral-shaped 3) flagellated bacteria 4) oxidase positive 5) urease positive 6) catalase positive
Unlike other bacteria, what does it metabolize, allowing it to thrive within the highly acidic stomach with a neutral environment?it metabolizes urea to ammoniaa
About _____% of the world's population is infected by H. pylori (although the percentage of symptomatic patients is much smaller?50
The best-known association with H. pylori infection is what disease?PUD
Eradication of H. pylori is associated with what 2 outcomes in PUD?1) improvement of symptoms 2) decreased rate of recurrence
What GI cancers have been linked with H. pylori infection?1) noncardiac gastric adenocarcinoma (about 1-3 % of infected patients) 2) mucosa-associated lymphoid tissue (MALT) lymphoma (< 0.1% of infected patients)
There is a inverse relationship between H. pylori and what carcinomas?1) cardia gastric CA 2) esophageal CA
Why is the relationship of H. pylori and other carcinomas (colon, gallbladder, pancreas) unclear?study results are inconsistent
Gastric CA affects about ____ million patients worldwide?one
Gastric CA is much more common in what country (with rates almost 10 times those seen in the US)?Japan
List symptoms of gastric cancer?1) vague 2) nonspecific
When does gastric cancer develope? after invasion of the muscular layer of the stomach
What is the 5 year survival rate of gastric cancer?< 15%
Why do strains of H. pylori differ in their virulence?probablyh related to various genomic factors and individual susceptibility variants
H. pylori has been shown to invade gastric epithelium cells and interact with the immune cells of the lamina propria leading to what?1) a humoral and cellular immune response 2) alterations in cell tight junctions 3) derangements of cell turnover 4) apoptosis
In patients infected with H. pylori, high dietary of _____ and _____ use both independently increase the risk of a patient developing gastric cancer?1) salt 2) tobacco use
Since H. pylori infection is so common but gastric CA is so uncommon, studies have attempted to identify what strategies to see which patients would benefit from screening and treatment?risk stratification
What is the risk stratification regarding the above question currently?none has been identified
Perhaps what will eventually allow for development of an effective screening and treatment strategy?1) identification of high-risk H. pylori strains 2) host factors that increase risk (exposures, genetic polymorphisms, host responses)
What are 2 reasons for screening patients with PUD for H. pylori?1) to improve the symptoms and recurrence rates 2) reduce the risk of developing gastric CA
True or false? Studies have not shown that infected patients who underwent eradication strategies for PUD had a lower incidence of gastric cancer then those who did not?False (infected patients who underwent eradication strategies for PUD HAD a lower incidence of gastric cancer than those who did not)
Eradication also reduced the number of ______ lesions present?premalignant
*** A Cochrane review concluded that there was limited, moderate-quality evidence that searching for and eradicating H. pylori REDUCES the incidence of gastric cancer in healthy, asymptomatic, infected Asian individuals, but the data was insufficient to extrapolate this to what populations?other
*** SUMMARY = H. pylori infects about _____% of world's population?50
*** SUMMARY = List the 2 cancers that are associated with H. pylori infection?1) gastric cancer (noncardia) 2) mucosa-associated lymphoid tissue (MALT) lymphoma
*** SUMMARY = Eradication of H. pylori reduces the risk of what in those with PUD?gastric cancer