Term
| Acidic, spicy foods, smoking - causal or associated with gastric ulcers? |
|
Definition
| Associated. H. pylori is the cause |
|
|
Term
| Helicobacter microbiological features |
|
Definition
| Gram Negative helical/curved rod, has a tuft of several polar flagella |
|
|
Term
| H. pylori epidemioogy (transmission, incidence of carriage) |
|
Definition
| Fecal-oral or oral-oral. High rate of carriage but low % of disease |
|
|
Term
| Factors which let H. pylori survive acidic conditions |
|
Definition
| Urease (produces NH3, raising local pH and damaging cells in the process), Flagella (gets to higher pH mucin layer more quickly) |
|
|
Term
| H. pylori mucinase, phospholipases |
|
Definition
| Liquifies mucin so it can get through |
|
|
Term
| H. pylori adhesins (BabA, SabA, HpaA) |
|
Definition
| Allows bacteria to resist high flow rate in stomach |
|
|
Term
| H. pylori LPS and flagellin |
|
Definition
| Non-toxic (Flagella poorly recognized by TLR5) |
|
|
Term
| H. pylori - Catalase, arginase, superoxide dismutase |
|
Definition
|
|
Term
|
Definition
| Inhibits T cell proliferation, B cell antigen presentation. Also triggers cation influx to KILL GASTRIC CELLS, and loosens junctions |
|
|
Term
|
Definition
| Neutrophil activation protein - stimulates immune cells to produce ROS (chronic inflammation) |
|
|
Term
|
Definition
| Promotes NF-kB activation and IL-8 production (chronic inflammation). Associated with cancer |
|
|
Term
| H. pylori - fates of chronic superficial gastritis (chronic inflammation) |
|
Definition
| 1) Peptic ulcer disease, 2) Lymphoproliferative disease (B cell MALT Lymphoma), 3) Chronic atrophic gastritis (Gastric adenocarcinoma = cancer!) |
|
|
Term
|
Definition
|
|
Term
|
Definition
| Use antibiotic + protein pump inhibitor since many antibiotics don't work at low pH |
|
|
Term
| Campylobacter microbiology |
|
Definition
| Gram-, spiral shape (like Helico) |
|
|
Term
| C. jeujuni - clinical features |
|
Definition
| 2-5d incubation, fever, abdominal pain, bloody diarrhea for 1 wk |
|
|
Term
| C. jeujuni - epidemiology |
|
Definition
| #1 cause of bacterial gastroenteritis (along with Salmonella). Very low infectious dose; mostly transmitted by chicken |
|
|
Term
|
Definition
| Damages intestinal mucosa --> ulcerated/bloody --> Cryptic abcesses in epithelial glands --> Neutrophil, monocyte, eosinophil infiltrate into lamina propria |
|
|
Term
|
Definition
| Cytolethal distending toxin (CDT) - delivers DNAse (CdtB) to host cell, which blocks mitosis and may trigger apoptosis |
|
|
Term
| Guillain-Barre Syndrome features |
|
Definition
| Paralysis for weeks due to autoimmune demyelination. Treat with respiratory, plasma exchange, corticosteroids |
|
|
Term
| C. jejuni and Guillain-Barre Syndrome Relationship |
|
Definition
| C. jejuni LOS closely resembles myelin, so once immune system mounts response to the LOS, it also targets self myelin |
|
|
Term
| Other bacteria which can cause Guillain-Barre |
|
Definition
| Haemophilus influenzae, Mycoplasma pneumoniae, some viruses |
|
|
Term
|
Definition
| ELISA for Campy common antigen; Gram-stain; culture in selective medium, with low O2, at 42C |
|
|
Term
| Key distinguishing features between helicobacter and campylobacter |
|
Definition
| Urease (H: +, C: -), Flagella (H: Several, C: 0-1), Optimum temperature (H: 37, C: 42), only Campylobacter is invasive (dystentery) |
|
|
Term
| Vibrio diseases and source of transmission |
|
Definition
| V. cholerae (cholera) - rice-water diarrhea, severe fluid/electrolyte loss. V. parahemolyticus - explosive watery diarrhea, seafood-caused. V. vulnificus - necrotizing fascitis if infects wound. All can come from contaminated water or shellfish |
|
|
Term
| V. cholerae - clinical presentation |
|
Definition
| Abrupt onset of watery diarrhea, vomiting, rice-water stool (w/ mucus), metabolic acidosis, hypokalemia, hypovolemic shock, cardiac arrhythmia, kidney failure |
|
|
Term
| V. cholerae - epidemiology |
|
Definition
| Contaminated water or food (much larger inoculum needed if in water). Mortality 60% if not treated in hours |
|
|
Term
| V. cholerae - cholera toxin (Ctx) |
|
Definition
| Cholera Toxin - Expressed by ctxAB genes, O1 and O139 serotype. Binary toxin: B binds GM1, A does ADP-ribosylation of Gsalpha protein |
|
|
Term
|
Definition
| Regulates cAMP levels; modification by Cholera Toxin causes it to stay on --> hypersecretion of water/electrolytes |
|
|
Term
| V. cholerae - Cholera toxin is related to enterotoxin of which other enteropathogenic disease |
|
Definition
|
|
Term
| V. cholerae - Ctx-negative strains, virulence mechanism |
|
Definition
| Zot and Ace toxins - increase intestinal permeability and fluid secretion, respectively. Ctx negative strands are milder forms |
|
|
Term
| V. cholerae - general pathology |
|
Definition
| Ingestion, rapid mvt through stomach (flagellum), adhesins, making Ctx, Zot, Ace toxins, fluid & ion loss |
|
|
Term
|
Definition
| Rehydration; antibiotics not necessary but may shorten the course |
|
|
Term
| Cholera & campylobacter diarrhea types |
|
Definition
| Cholera - secretory (watery) diarrhea; Campylobacter - dysentery (low volume, blood, mucus with WBCs) |
|
|
Term
| V. parahaemolyticus epidem/clin features |
|
Definition
| Explosive watery diarrhea, self-limiting, #1 cause of seafood-associated gastroenteritis |
|
|
Term
| V. parahaemolyticus virulence - hemolysin, capsule |
|
Definition
| Hemolysin - enterotoxin inducing chloride secretion, tissue damage. Capsule is antiphagocytic |
|
|
Term
| V. vulnificus - clin/epidem |
|
Definition
| Diarrhea, nausea, etc. Worse in immunocompromised patients (bacteremia, septic shock). Can cause necrotizing fascitis if enters wounds. #1 cuase of seafood-related US deaths (50% mortality) |
|
|
Term
| V. vulnificus - virulence factors |
|
Definition
| Main one is capsule - antiphagocytic and resists compliment |
|
|
