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33 Cards in this Set
- Front
- Back
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Characteristics of Campylobacteria & heliocbacter
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spiral
gram negative low G/C content unable to ferm/oxidize carbs impt pathogens (diarrhea, gastric ulcers, cancer) |
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General characteristics of campylobacter
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GI pathogens
grossly bloody stools GI distress 24 hr |
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Guilliane Barre syndrome is and is associated with what bacteria?
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demyelinating illness
2-3 wks after diarrhea cympylobacter |
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What is the resevoir for campylobacter?
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c. jejuin in supermarket chicken
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Characteristics of human pathogens c. jejuni and c. coli of campylobacter?
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gram negative
curved rod - comma shaped able to grow at inc temps non-fermentative motile w single flagella serologically diverse |
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What is the incubation period of campylobacter?
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1-7 days with a median onset at 2-4 days
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Where do campylobacter replicate?
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both small and large intestines
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How is campylobacteria similar to ulcerative colitis?
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similar inflammatory response
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What is the epidemiology of campylobacter?
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more frequent than salmonella, shigella or e. coli
highest in summer |
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Toxin of campylobacter is?
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CDT - cytolethal distending
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What does CDT do?
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toxin of campylobacter
inerupts cell cycle progression |
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Where else can you find CDT besides campylobacter?
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shigella dysenteriae adn e. coli
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How do you diagnois and tx campylobacter?
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darting motility in fresh stool and PCR
fluid replacement and electrolyte balance |
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What drugs can you use to treat campylobacter?
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erythromycin
fluoroquinolone tetracyline |
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What is the clinical importance of H. pylori?
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associated w. chronic superficial gastritis
50% of ppl infected peptic ulcer disease gastric carcinoma |
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What are the general characteristics of h. pylori?
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gram negative
curved rod multi-polar flagella urease production colonizes mucus layer overlaying gastric mucosa |
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Population genetics and diversity of h. pylori?
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aquired in childhood
familys have same strain mixed infections are uncommon |
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What is BabA?
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in H. pylori
binds to lewis b blood group Ag expressed on gastric epithelium |
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What is the significance of the LPS of h. pylori?
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contains structure identical to fuscocylated lewis x & y blood group Ag
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Why is it important that h. pylori are motile?
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ability to swim below the lumen to a higher pH
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What is urease?
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an enzyme in h. pylori that converts urea to NH3 and CO2 to inc pH of immediate area
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What are the histological findings of pathogenesis of h. pylori
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inflammatory infiltrates with PMNs
lymphocytes eosinophils |
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What is NAP?
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H. pylori
neutrophil activating factor |
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What is VacA?
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h. pylori
interfers w intracellular vesicle trafficking vacuole formation maybe resposible for gastric erosin |
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What is CagA
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h. pylori
cytotoxin VacA assoiciated gene |
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What is Cag locus?
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h. pylori
pathogenicity island encoding for type IV secretion |
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Cag + strains of h. pylori are strongly associated with what?
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peptic ulcers and cancer
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What is the first step in h. pylori infections?
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urease neurtralizes amonia allowing survival in acid and swim to adhere to the lewis b blood group stuff (BabA and LPS)
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After binding the lewis b blood group BabA h. pylori does what?
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type IV secretion apparatus via CagA translocation
IL-8 - inflammation activates protonocgene c-fos to get serum response element trans-activation |
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After Cag A gets into the cell what happens?
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tryosine P
alters cytoskeleton - pedestal induces IL8 release - inflam |
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After CagA causes modification what is the last step in h. pylori infection?
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VacA is bound and internalized
this is a multifxn toxin |
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What are the functions of VacA toxin in h. pylori?
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forms anion-specific channel
forms large vacuoles alters tight junctions induces gastric epithelial erosion |
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How do you diagnose helicobater?
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phase contrast
urea breath test!!! antibodies enzyme immunoassay |
