Infection Biology and Diagnosis Flashcards
This is defined as a measure of a microbe’s ability to cause disease.
VIRULENCE
Defined as the number of organisms required to cause disease in 50% of the population.
ID50
These are inanimate objects that can harbor pathogens
FOMITES
What do you call the surface proteins which mediate binding to endothelium and to extracellular proteins such as fibronectin which is presnt in SALMONELLA and E. coli?
CURLI proteins
This enzyme is also known as “spreading factor”.
HYALURONIDASE
Which 4 bacteria has IgA protease?
Strep pneumoniae, H. influenzae, Neisseria meningitidis and gonorrhoeae (these organisms live in a mucus-rich environement in the lungs and genitourinary tract where IgA is ABUNDANT so they logically need to have a protease)
What do you call the substance produced by Staph aureus which destroys both neutrophils and macrophages?
Panton-Valentine Leukocidin
Bacterial capsule prevents which host defense mechanism?
PHAGOCYTOSIS
This cell wall protein of Staphylococcus aureus prevents complement activation.
Protein A
All EXOTOXINS are HEAT-LABILE except?
Staphylococcal enterotoxin (classic example of why reheating salad would not prevent food poisoning)
Which is the toxic comnponent of LPS which induces the overproduction of cytokines such as TNF and IL-1?
Lipid A
Endotoxins can be assayed usinh which test?
Limulus Test
The alpha toxin of Clostridium perfringens is called?
LECITHINASE
This agar distinguishes lactose fermenters from non-lactose fermenters and H2S producers from non-producers.
Triple Sugar Iron (TSI)
Which bacteria grow in TELLURITE agar?
Corynebacterium
Thayer Martin Agar is used for selective growth of N. gonorrhea from NONSTERILE SITES. It is composed of which 3 antibiotics ?
Vancomycin (for Gram +); Colistin (for Gram -); Nystatin (for FUNGI)
Which bacteria grow in Chocolate + Factors X and V
H. influenza
Cetrimide agar is used to isolate which bacteria?
Pseudomonas
Thiosulfate Citrate Bile salts (TCBS) grow which bacteria?
Vibrio cholerae (Think TCVS instead)
Which bacteria grow in Eaton? XLD? Charcoal yeast? Skirrows? BSK? Bordet-Gengou/Regan Lowe?
Eaton = Mycoplasma pneumoniae; XLD = Salmonella’ Shigella; Charcoal yeast = Legionella; Skirrows = Campylobacter, Helicobacter; BSK = Borrelia burgdorferi; Bordet-Gengou = Bordetella
Fletcher’s agar or EMJH grow which organism?
Leptospira interrogans
Which gene confers resistance to methicillin?
mec gene found in MRSA
