Gill lecture 1 Flashcards
T or F: Many virulent proteins associated with G pos bacteriaa are associated with virulence.
TRUE
What does lipid A make?
Endotoxin
What lab tests looks for o-side chains in G neg bacteria?
Serotyping
What is the significance of porins on G neg bacteria?
They are susceptible to certain drugs that can go through this pore that will not affect G pos bacteria (no pore).
T or F: Gram pos bacteria make endotoxin.
False. Gram neg only
What are the gram + rod genuses that we need to know?
Clostridium
What are the Gram + cocci genuses that we need to know?
Staphylococcus, streptococcus, enterococcus
T or F: Up to 30% of people care staphylococcus aureus in our noses.
TRUE
Where does staphylococcus like to hang out?
Anterior nare and perineum
T or F: Different strains of staph have varying amounts of virulence.
TRUE
What are the most common diseases can staph cause?
Cutaneous (localized abscess/boil), toxogenic infections (food poisoning), pneumonia (high mortality)
What drugs are staph resistant to?
Penicillin, methicillin, emerging vancomycin
What does staph use to adhere to tissue?
Fibronectin-binding protein
What toxin does staph aureus produce?
Alpha-toxin - damages tissues and interferes with phagocytosis.
What does staph use to impair phagocytosis?
Coagulase and fibrinogen (wall off the cell from pathogens), protein A (bind antibody backwards to surface of cell)
T or F: Staph infections are often associated with foreign bodies (splinter, suture, piercing).
TRUE
What is scalded skin syndrome?
Caused by staph aureus secreted toxin (serine protease) that cleaves desmosomes and results in desquamation. Systemic in infants and more localized in adults.
T or F: Scalded skin syndrome is cause by hot water burns.
False. Caused by staph aureus desquamation
What is toxic shock syndrome?
Caused by staph aureus. Local release of toxin (superantigen) that results in system effects. High fever, shock, vomiting, muscle pain, finally resulting in renal and hepatic injury
What two things must be fulfilled to get toxic shock syndrome?
The right strain (with TSST gene) and right environment (oxygen, neutral pH, high protein)
What is a superantigen?
An antigen that is so potent it can cause non-specific activation of T cells. Results in toxic shock syndrome in staph aureus infection.
T or F: Staph epidermidis produces coagulase.
False.
T or F: Staph epidermidis produces slime.
True. Allow biofilm formation
T or F: The big problem with Staph epidermidis is that it binds to foreign bodies (heart valves, prostheses).
TRUE
What is the importance of biofilms in S. epidermidis?
Protects them from antibiotics
T or F: Streptococcus pneumonia produces coagulase.
FALSE
T or F: Streptococcus pneumonia is the most common cause of community acquired pneumonia.
TRUE
How does strep pneumonia evade host defenses?
Antiphagocytic capsule (91 antigenic types)
How does your immune system fight strep pneumonia?
Make antibody to strep capsule
T or F: Strep pneumonia part of normal flora in up to 40% of the population.
TRUE
What are the predisposing factors for pneumonia infection?
Being young or old, alcoholism (interferes with mucociliary action in lungs), respiratory viral infection
Why do the young struggling with pneumococcal disease?
Young children are not good at mounting an immune response to polysaccaride antigens.
What are the invasive forms of pneumococcal bacteria?
Menigitis and bacteremia
T or F: The pneumonia vaccine always protects against pneumonia.
False. Protects against the invasive form of strep.
If young children can?t make vaccines to polysaccharide, how can we make a vaccine to strep for them?
We conjugate the polysaccharide to protein.
How many serotypes are in the strep vaccine for adults? children?
23; 7 and 13.
T or F: You should not find enterococci in an healthy adult.
False. Pretty much everyone has them in their intestines.
Where are the most common sites of infection for enteroccocus?
Urinary tract, surgical wound, biliary tract.
T or F: Enterococci are very easy to kill with antibiotic.
False. Tend to be very antibiotic resistance.
T or F: Enterococci are common culprits in nosocomial infections.
TRUE
T or F: Most Gram pos rods are a staph.
False. Most are clostridium
T or F: Clostridia can form spores.
TRUE
T or F: Clostridia are aerobes.
False. Strick anaerobes
What are the major diseases caused by clostridium?
Tetanus, botulism, gangrene, other tissue infections
Which form of clostridium is typically seen in the hospital?
C. difficile
T or F: C. difficile is found in the gut of up to 10% of the population.
TRUE
T or F: C. diff spores can be killed with alcohol-based hand sanitizers.
False.
T or F: C. diff is very antibiotics.
TRUE
