MIP: Gram Positive Pathogenic Bacteria Flashcards
What TLR detects peptidoglycan and lipoproteins in Gram + bacterial cell walls?
2
What TLR detects flagella?
5
What are the major subdivisions of the Gram Positive Cocci?
Staphylococcus, Streptococcus, and Enterococcus facalis
Why can’t acid-fast organisms be Gram stained?
They have lipoarabinomannan (LAM) in their cell walls
Why are acid-fast bacteria difficult to treat?
They have a very slow doubling time and they have a high mutation rate and LAM
Where is Staph aureus found?
It is part of normal and transient flora in humans and is foudn in moist pllaces (skin, armpit, nasopharynx, nares, groin)
Why is S. aureus an apt name?
Many strains produce the anti-oxidative gold pigment, staphoxanthin
What hemolysis pattern is seen with S. aureus?
Beta-hemolysis
What is the action of coagulase?
Converts fibrinogen to fibrin and coagulates plasma
True or False: Coagulase is found in all Staphylococcus bacteria.
False- not in epidermis or saprophyticus
What is the selectivity and differential capacity of a mannitol agar plate? How will S. aureus streak?
The selective component is salt, and the differential components are mannitol and phenol red; S. aureus turns the plate from red to yellow
What is the spectrum of disease that is caused by S. aureus?
Boils, furnicules, styes, impetigo, osteomyelitis, cellulitis, mastitis, UTIs, acute endocarditis, meningitis, TSS, food poisoning, scaleded skin syndrome, pneumonia, empyema, septic arthritis
What host factors increase susceptibility to Staph aureus infection?
Breaches in the skin, immunological defects, foreign bodies, close quarters coupled with poor hygiene, previous damage to tissues
How does S. aureus’s Protein A work?
It binds to the Fc portion of IgG and prevents its binding to phagocyte and facilitating of phagocytosis
What is an abscess?
Collection of pus (caused by neutrophil degranulation)
What is a furuncle? A carbuncle?
A furuncle is an abscess into subcutaneous tissue and a carbuncle is multiple contagious abscesses
How do you treat abscesses, furuncles, and carbuncles?
Incising the wound, draining it, and antibiotic therapy
What S. aureus toxin causes hemolysis and necrosis of the skin?
Alpha toxin