9-2 Staph/Strep/Enterococci Flashcards
[T or F]
Micrococci are NOT associated with disease
TRUE
Defects in _______ and _________ can predispose an individual to [Staph Aureus] Infection.
Name the 6 Dz that can cause Leukocyte Chemotaxis
Defects in [Leukocyte Chemotaxis] and [Ab Opsonization] can predispose an individual to Staph Aureus.
Name the 4 Dz that can cause Leukocyte Chemotaxis
“A [DJ from DR] can ruin ur [Leukocyte Chemotaxis]”
- Down Syndrome
- Job’s Syndrome
- DM
- Rheumatoid Arthritis
Name the 6 usual sites of infection for [Staph Aureus]
Staph Aureus typically infects areas in which it is Normal Flora
1) Skin
2) Anterior Nares
3) Throat
4) GI
5) Vagina
6) Urethra
Carbuncle
B: Two places they’re mostly found
an Abscess larger than a boil with 1 or more opening draining pus onto the skin
B:
- Back
- Nape of the Neck
3 Toxin-Mediated Infections associated with [Staph Aureus]
- Scalded Skin Syndrome (neonates and children under 4)
- Toxic-Shock syndrome
- Food Poisoning
Panton-Valentine Leukocidin (PVL)
[Staph Aureus] enzyme that alters leukocyte permeability to allow cations to pass—> Leukocyte Destruction
STAPH AUREUS VIRULENCE FACTOR :
a-hemolysin (3)
- Lyses RBC of several animals
- Dermonecrotic on SubQ injection
- Leukocyte toxicity
STAPH AUREUS VIRULENCE FACTOR :
B-hemolysin (2)
ºSphingomyelinase –> varying hemolysis of RBC due to differences in membrane sphingomyelin content
ºProduces HOT-COLD lysis in which hemolysis is ENHANCED at COLD temperatures after 35ºC incubation
STAPH AUREUS VIRULENCE FACTOR :
DELTA-hemolysin (3)
- Produced by 97% [Staph Aureus]
- acts as surfactant to disrupt cell membrane and form channels that increase over time—> leakage
- Some [coag-NEG Staph] can use this to cause NEC in neonates
STAPH AUREUS VIRULENCE FACTOR :
Hyaluronidase
Hydrolyzes intercellular matrix of acid mucopolysaccharides in tissue –> allows [S.Aureus] to spread to adjacent tissue
STAPH AUREUS VIRULENCE FACTOR :
Phospholipase C
A: 2 types of pt its found in
B: Function
STAPH AUREUS VIRULENCE FACTOR
A: Found in pt with ARDS & DIC
B: Causes tissues to become more susceptible to damage by [bioactive complement components]
A: List the 3 Superantigen Toxins of [S.Aureus]
B: Name the 2 Biologic Characteristics they all display
A: [PYROGENIC TOXIN SUPERANTIGENS]
1) Toxic Shock Syndrome Toxin -1 (TSST1)
2) Strep Pyrogenic Exotoxins (SPE)
3) [Strep superantigens]
B: •All of these induce Polyclonal T-cell proliferation
•Enhance lethal effects of small amounts of endotoxin
A: Which bacteria is the 2nd most common cause of uncomplicated cystitis in [women in college/child-bearing age]?
B: What’s the FIRST most common cause?
C: The bacteria in (A) is RESISTANT TO ______ but susceptible to ______
A: 2nd most common cause= Staph Saprophyticus
B: E.Coli is 1st
C: [Staph Saprophyticus] is [RESISTANT TO NOVOBIOCIN] but [susceptible to Furozolidone]
A: What is special about [Staph Lugdunensis]?
B: Where does this bacteria typically colonize?
A: Only species that is both [PYR AND Ornithine Positive]!
B: Human Inguinal Area
A: What is [SCCmec]
B: What does the mecA gene do?
A: The [SCCmec] is a [Staph Aureus] mobile chromosome that encodes for mecA
B: mecA is a gene that alters [Penicillin Binding Protein] —> [PBP2a] which allows [Staph Aureus] to become [Methicillin/B-lactam Abx RESISTANT]
3 Substances that can GENERATE ERRORS during a [PCR MRSA nasal test] for pts?
- Whole Blood
- Mucus
- Nasal Spray
Which bacteria is associated with [Skin and Soft Tissue Infection]
MRSA
Streptococci prefers [______ atmosphere] and require ______ media to grow
Streptococci prefers [Anaerobic/CO2 atmosphere] and require COMPLEX media to grow
A: Why does [Strep Pyogenes] reoccur?
B: How is it transmitted?
A: [Strep pyogenes] reoccurs due to the lack of an Antibody to the M-protein
B: [Strep Pyogenes] is transmitted by Respiratory Droplets
A: What bacteria is Scarlet Fever associated with?
B: What toxin causes this?
C: Explain the symptom manifestation
D: When does it appear exactly?
E: What key characteristic sign should it display?
F: When does it resolve?
A: Scarlet Fever is associated with [Strep Pyogenes - Group A]
B: Caused by Erythrogenic exotoxin
C:
1st starts as Rash w/tiny red bumps on chest, abdomen and behind ears BUT SPARES THE FACE
D: Appears 12-48 hours after the fever
E: Fine, red and rough-textured BLANCHES on pressure
F: Rash resolves 3-4 days after onset and then DesQuamation begins
What’s the difference between [Staph Aureus Toxic Shock] and [Strep Pyogenes Group A Toxic Shock]
Unlike pt with [Staph Aureus Toxic Shock], [STREP Pyogenes Group A Toxic Shock] will result in a Positive Culture
A: Puerperal Sepsis
B: Who is this typically seen in?
A: [Strep Pyogenes] colonizing the genital tract or from Ob/Gyn Doc invade upper genital tract —>
[Strep Pyogenes Group A Toxic Shock] / [necrotizing fasciitis] /lymphangitis
B: Seen in women post delivery or post abortion
A: List the 2 Main sx of [Post-Streptococcal Sequelae]
B: Which strep is this associated with?
- Rheumatic Fever
- Glomerular Nephritis
B: [Strep Pyogenes Group A]
A: Rheumatic Fever Description
B: When does this reoccur?
C: List 4 symptoms
D: This is 1 of the 2 symptoms for what syndrome?
A: Nonsuppurative inflammation occurring 1-5 weeks after [Strep pharyngitis]
B: Attacks reoccur into adulthood
C:
- Fever
- [SubQ Nodules]
- Chorea
- [Characteristic Cardiac lesions - Aschoff bodies and mitral valve damage]
D: Syndrome: [Post-Streptococcal Sequelae]
A: Acute Glomerulonephritis 2º to [Post-Streptococcal Sequelae] occurs when? Etiology?
B: Name 4 sx
C: Which bacteria causes this?
D: Why does this reoccur consistently?
A: Occurs AFTER a skin/respiratory infection. [Antigen + Ab + C] all deposit in the glomeruli
B:
a) edema
b) HTN
c) hematuria
d) proteinuria
C: [Strep Pyogenes Group A]
D: [Strep Pyogenes] has different [M Proteins] which allows for it to evade the immune system upon reoccurrence and some [M proteins] will illicit a more nephropathogenic etiology
A: Compare Virulence Factors [Streptolysin S vs. Streptolysin O] in ______ bacteria
B: What are 3 other [Virulence factor enzymes] for this bacteria?
C: What 2 enzymes allow this bacteria to spread into other tissues?
[Strep Pyogenes]
A: [Streptolysin S]= O2 stable / non-antigenic
vs.
B: [C5a peptidase] / Hyaluronidase / Streptokinase
C: Streptolysin and Streptokinase allow [Strep Pyogenes] to spread into other tissues
A: [M Protein] binds to ______ cells and allows bacterial ______. It’s Antiphagocytic because it DEGRADES ______.
B: How is the bacteria eradicated? (4)
A: [M Protein] binds to epidermal cells and allows bacterial survival. It’s Antiphagocytic because it DEGRADES [COMPLEMENT C3b].
B:
1) Antibodies to [M protein] activate complement and then kill the bacteria
2) Penicillin/Ampicillin/Amoxicillin = NO RESISTANCE WORLDWIDE
3) Cephalosporins
4) Erythromycin (Use in Penicillin allergic pt)
A: [Strep Agalactiae GBS - (Group B Strep)] is normal flora in what 3 areas?
B: What sx does it cause in Adults?
C: Early Onset Neonatal Sx
D: Late Onset Neonatal Sx
E: How does Sialic Acid play a role?
A:
- Throat
- Vagina
- [GI tract]
B: Skin and wound infections (Diabetic Adults)
C: Early Onset Neonatal (1st week of life) = [Bacteremia/ Meningitis/ PNA]
D: LATE Onset Neonatal (1 week-3 mo.)= Bacteremia w/Meningitis
E: Sialic Acid on Polysaccharide Capsule inhibits Complement –> allows GBS to multiply
Other Beta-Hemolytic Strep:
Group C (3)
- Veterinary Infections
- College Pt Pharyngitis
- Sepsis
Other Beta-Hemolytic Strep:
Group F
Associated with Abscesses
Other Beta-Hemolytic Strep:
Group G (2)
- Pharyngitis
2. Sepsis in neonates and Elderly
A: Where is [Strep Viridans] the normal flora of? What MAJOR Dz does is cause?
B: List 2 more rare Diseases for this bacteria
C: What important components does this bacteria LACK? (2)
A: Normal Flora of Upper Respiratory Tract and MAJOR cause of [Dental Caries]
B:
- Important cause of Endocarditis
- [sepsis in a neutropenic CA pt]
C: Lacks Hemolysins and [Beta Strep toxins]
A: The BOVIS Group from [Strep ______] consist of non-enterococcal group __ strep that includes:
S. bovis 1 = from (3)
S.bovis 2= from ______
S.bovis 3= from (2)
B: What is the clinical significance of the BOVIS group? (2)
A: The BOVIS Group from [Strep Viridans] consist of non-enterococcal group D strep that includes:
S. bovis 1 = from humans/cattle/[koala bears]
S.bovis 2= from Humans
S.bovis 3= from Human and Bovine
B:
- BOVIS is strongly associated with presence of [COLON CARCINOMA].
- It can cause bacteremia and [native or prosthetic valve-endocardidits]
A: [Strep Milleri] includes what 3 bacteria? What’s unique about the culture of this on agar?
B: Where is it normal flora?
C: Sx
A: [Strep Milleri] includes CAI [Constellatus/Anginosus/Intermedius] and has a butterscotch odor when cultured on agar plates
b: normally colonizes mouth/GI/vagina
C: Can cause DEEP-SEATED Pyogenic cardiac and CNS infections and often isolated from brain abscesses
What are the 2 Nutritionally Deficient Strep Bacteria?
- Abiotrophia
2. Granulicatella
List 4 Common ENTEROCOCCAL Infections
- [Mixed bacterial wound infections and decubiti]
- UTI
- Sepsis
- Endocarditis
“ENTEROCOCCAL Infections will lead to a [MUSE] “
What color colonies does [Enterococcal Casseliflavus] produce?
[Enterococcus casseliflavus] produces YELLOW colonies
A: What 3 Abx is [Enterococcal] bacteria INTRINSICALLY resistant to?
B: [Enterococcal] is the 2nd most cause of what type of pathogen?
Intrinsically resistant to all
(x) cephalosporins
(x) aminoglycosides
(x) trimethoprim-sulfa
” [Enterococcal] is intrinsically resistant to the CAT”
B: Nosocomial Pathogen (Hospital-Acquired Dz)
Name the 3 Recommended Tx for [Strep Pneumoniae]
- Penicillin if susceptible
- [Cefotaxime or ceftriaxone] if susceptible
- Alternative agents: Macrolides
