Mod3: Staph, ecoli, candida

Question 1

Pathological effects/properties streptoccal bacteria

Answer 1

hemolyze RBCs (alpha-incomplete,beta-comp, gamma-non)
gram positive

Question 2

Group A Beta-hemolytic streptococci
s/s
phagocytosis resistant d/t
Virulence

Answer 2

strep, post strep golmerular nephritis
scarlet/rheumatic fever
hyaluronic acid capsule=phagocytosis resistant
most virulent, rapid spreading thru tissue, lymph, blood

Question 3

Group A Beta-hemolytic streptococci virulence factors

3

Answer 3

M protein: protects from phagocytosis=^virulent
Streptolysin O: protein destroys rbc/wbc
(antistreptolysin=antibody
streptokinase:enzyme activates plasmin (dissolves clots so bacteria can escape)
Extoxin: streptococcal TSS, scarlet fever

Question 4

Group B Beta-hemolytic Streptococcal bacteria
found in 
cause infections in
risk factors
causes 4 types of infections

Answer 4

vaginal, lower GI~neonatal meningitis
cause infections in elderly/immunocompromised
dm, ca, old, cirrhosis, corticosteroids, HIV
bacteremia, skin/soft tissue, respiratory, GU

Question 5

Enterococci streptococci bacteria:
Faecalis & Enterococcus faecium
cause infections where
contain what
requires \_\_ & \_\_ for treatment

Answer 5

normal flora, cause nosocomial infections in urinary/biliary tract, wounds, blood
contains penicillinase (resistant to PCN)
requires ampicillin & aminoglycoside

Question 6

VRE vanc resistant enterococci
cause
what makes it resistant
risk factors

Answer 6

cause nosocomial infections
different phenotypes make it resistant to vanc, can be life threatening
use of cephalosporin/fluoroquinolones, critically ill

Question 7

Staphylococcus Aureus

Answer 7

gram positive
nosocomial and skin/soft tissue infections
normal flora found in nares/skin

Question 8

Staphylococcus Aureus produces what to help it

4

Answer 8

surface proteins: attach to endothelium/tissues
protein A: binds to IgG antibody, masks bacteria from it
coagulase: produces clotting on exterior bacteria to hide from immune system
produce others to protect from complement mediated lysis

Question 9

MRSA
methicillin resistant staphylococcus aureus
resistant d/t
risk factors:

Answer 9

B-Lactamase

use cephalosporins/fluoroquinolones, hosptilization, nursing home, invasive medical devices, dialysis

Question 10

Ecoli can cause

enteropathogenic ecoli can cause
enterotoxigenic
shiga toxin producing ecoli

Answer 10

diarrhea, hemolytic uremic syndrome, uti
gram negative rod that is normal flora in gut, leading cause of meningitis in infants
developing countries infant diarrhea
travelers diarrhea, diarrhea in developed countries infants
hemorrhagic colitis

Question 11

Candida

Answer 11

most common fungal infection
normal flora, opportunistic, on skin, mucous membranes, GI
infections in catheters, iv, PD caths
has adhesion factors to bind to devices, skin, leukoctyes~ tissue invasion

Question 12

Candida complications

Answer 12

kidney, brain, liver abscess

shock, DIC, death