Gram positive Bugs Flashcards
1
Q
Define the bug that is
- Novobiocin resistant
- Novobiocin sensitive
A
- Stapholococci Saprophyticus
- Stapholococci Epidermidis
2
Q
Define the bug that is
- Optochin resistant
- Optochin sensitive
- Bacitracin resistant
- Bacitracin sensitive
A
- Streptococcus viridans
- Streptococcus pneumoniae
- Streptococcus group B
- Streptococcus pyogenes (group A)
3
Q
- what is the term for organisms that form green ring around colognies on blood agar?
- What forms a green ring around colonies on blood agar?
- provide 2 distinguishing features
A
- Alpha-hemolytic organisms
-
Streptococcus pneumoniae
- Catalase neg
- Optochin sensitive
-
Streptococcus Viridians
- Catalase neg
- Optochin resistant
4
Q
- What is the term for organisms that form clear area of hemolysis on blood agar?
- Name the 4 organisms that form clear area of hemolysis on blood agar
- give 2 distingusihing characterisitics
A
- Beta hemolytic bacteria
-
Staphylococcus aures
- Catalase +, coagulase +
-
Streptococcus pyogenes group A
- Catalase -, Bacitracin sensitive
-
Streptococcus agalactiae group B
- Catalse -, Bacitracin resistant
-
Listeria monocytogenes
- Tumbling motility, meningitis in newborns, unpasteurized milk.
5
Q
Presentation
Gram positive cocci in clusters, Protein A (virulance factor) bings to Fc IgG inhibiting complement activation and phagocytosis. Commonly colonizes the nose.
- Define organism
- Causes
A
- Staphylococcus aureus
- Causes
- Inflammatory disease
- skin infections, organ absecesses , pneumoniae (often after influenza virus infection), endocarditis, and osteomyelitis
- Toxin-mediated disease
- toxic shock syndrome (TSST-1), scalded skin syndrome (exofoliative toxin), rapid onset food poisoning (enterotoxins)
- MRSA (methicillin resistant S. aureus infection)
- important cause of serious nosocomial and community acquired infections, resistant to methicillin and nafcillin b/c of altered penicillin-binding protein.
- Inflammatory disease
6
Q
Toxin mediated disease
- TSST is a superantigen that bings to what 2 receptors and results in what?
- Presents as fever, vomiting, rash, desquamation, shock, end-organ failure
- Use of what predisposes to toxic shock syndrome
A
-
2 receptors: MHC II and TCR receptor
- results in: polyclonal T-cell activation
- Vaginal and nasal tampons
7
Q
Define the organisms that:
- infects prosthetic devies and IV catheters (by producing adherent biofilms)
- Component of normal skin flora
- contaminates blood cultures
- Novobiocin sensitive
A
Staphylococcus epidermidis
8
Q
Food poisioning
- S. aures food posioning due to ingestion of what?
- What is the incubation time?
- Enterotoxin heat stable or liable
- Is it destroyed by cooking?
- How does it form abscess?
A
**Food poisioning **
- S. aures food posioning due to ingestion of what? pre-formed toxins
- what is the incubation time? 2-6 hrs (short time)
- Enterotoxin heat stable or liable
- is it destroyed by cooking? No
- How does it form abscess? Forms a fibrin clot aronud self
9
Q
Define the organism that:
- is the second most common cause of uncomplicated UTI in young women (first is E. coli)
- Novobiocin resistant
A
Staphylococcus saprophyticus
10
Q
Define the organism that
- Most common cause of
- Meningitis
- Otitis media
- Pneuomia
- Sinusitis
- Lancet shaped, gram+ diplococci, encapsulated IgA protease.
- Optochin sensitive
- **Pneumococcus: **
- Assocaited with rusty sputum, sepsis in sickle cell anemia, and splenectomy
- No virulence w/o capsule
A
Streptococcus pneumoniae
11
Q
Define the organism that
- Is alpha hemotylic and optochin resistant
- Which organism is found in the normal flora of the orpharynx and cause dental caries
- Which organism cause bacterial endocartidits at damaged valves
- what is its MOA
A
- Viridans group streptococci
- Streptococcus mutans
-
Streptococcus sanguis
- *sanguis= *blood
- MOA: makes dextrans, which bind to fibrin platelet aggregates on damaged heart valves.
12
Q
Define the organism that:
- Causes
- pyogenic: pharyngitis, cellulitis, impetigio
- toxigenic: scarlet fever, toxic shock like syndrome, necrotizing fasciitis
- immunologic: rheumatic fever, acute glomerulnephritis
- Bacitracin sensitive
- Antibodies to M protein enhance host defenses against _ _ but can give rise to rheumatic fever
- ASO titer detects recent infection of this organism
A
Streptococcus pyogenes
(Group A streptococci)
13
Q
Define
- Jones critieria
- Pharyngitis can result in what 2 things?
- Impetigo more commonly precedes what?
- Scarlet fever
A
- Jones critieria
- Joints (polyarthritis), heart (carditis), Nodules (subcutaneous), Erythemia marginatum (pink rings on trunk), Sydenham chorea (rapid uncoordinated movements)
- Pharyngitis–> fever and glomerulonephritis
- Impetigo: precedes glomerulonephritis than pharyngitis
- **Scarlet fever: **scarlet rash with sandpaper like texture, strawberry tongue, circumoral pallor
14
Q
Define the organism
- Bacitracin resistant, B-hemolytic colonise vagina, cause pneumonia, meningitis, & sepsis: mainly in BABIES!
- hippurate test +
- Produces CAMP factor
- define
- When do you screen pt and what do you give them?
A
- Streptococcus aglacteria (group B strep)
- CAMP factor: enlarges the area of hemolysis formed by S. aureus.
- Screen: 35-37 weeks
- Patients with + culture receive intrapartum penicillin prophylaxis.
15
Q
Define the organism that:
- is a normal colonic flora that is penicillin G resistant and cause UTI, biliary tract infections, and subacute endocarditis (following GI/GU procedures).
- what is Lancefield grouping based off of?
- what is included in this group?
- VRE (vancomycin resistant enterococci) are an important cause of nosocomial infection.
A
- Enterococci (group D streptococci)
- _Lancefield group: _based on differences in the C carbohydrate on the bacterial cell wall, variable hemolysis.
- Enterococci and the non enterococcal group D streptococci
