Micro- Diebel

Question 1

Describe the difference between alpha, beta, and gamma hemolysis

Answer 1

gamma= no hemolysis
Beta = will completely destroy RBCs
alpha = partial damages them

Question 2

What organisms have B-hemolysis?

Answer 2

Staph

Strep pyogenes

Question 3

What organism has alpha hemolysis?

Answer 3

Step viridans

Question 4

How would you distinguish between the different kinds of strep?

Answer 4

ALL: Gram +, cooci, catalse -

S.mutans= alpha hemolytic, bacitracin resistant

S. pyogenes = B-hemolytic, bacitracin sensitive

Question 5

Which of the strep species is bacitracin sensitive?

Answer 5

S. pyogenes

Question 6

What virulence factor is CAR proteins associated with? what do they do?

Answer 6

Pericarditis
Myocarditis
Binding proteins (attachment)

Question 7

What is the triad for RMSF?

Answer 7

Fever
Rash (hands and soles)
Headache

Will also see muscles aches, malasie

Question 8

What organism causes RMSF?

Answer 8

Rickettsia Rickettsia

Question 9

What is unique about rickettsia rickettsia?

Answer 9

Obligate intracellular parasite.
Needs to use host ATP
(Only other organism like this is clamydia)

Question 10

What organism produces dextran inorder to make a glycocalyx?

Answer 10

Strep viridans

Question 11

FimA

Gsp B

Answer 11

Strep vidirdans

Question 12

FnbpA

Answer 12

Staph

Question 13

M proteins

Answer 13

Found in strep pyogenes
Used to resist phagocytosis

Abs cross react w/meromyosin on heart and cause rheumatic heart disease

Question 14

What kind of hypersensitivity is Abs cross reacting with M protein and meromyosin?

Answer 14

TYPE II HYPERSENSITIVITY

Question 15

What does streptolysin O do?

Answer 15

Destroys RBCs

Question 16

What does streptolysin S do?

Answer 16

Destroys WBCs

Question 17

What does streptokinase do?

Answer 17

Converts plasminogen to plasmin

Question 18

What does hyalouronidase do?

Answer 18

Breaks down connective tissue

Question 19

What are the virulence factors for rickettsia rickettsia?

Answer 19

OmpA & OmpB - attachment

T4SS - host cell entry

Question 20

What is the age range for acute rheumatic fever?

Answer 20

5-14 years old

Question 21

What type of hypersensitivity is osler’s nodes and roth spots?

Answer 21

Type III hypersensitivity

Question 22

What is the most common cause of Community-Acquired Native Valve Endocarditis?

Answer 22

Streptococci

Question 23

Most common cause of nosocomial native valve endocarditis?

Answer 23

Staph aureus

Question 24

Which staph species is coagulase negative?

Answer 24

Staph Epidermidis

Question 25

What disease is this? "chest pain which becomes worse when patient is swallowing or supine is the most common symptom."

Answer 25

Pericarditis

Question 26

How does bacterial pericarditis differ from viral pericarditis?

Answer 26

more acute, severe and has fever and tachypnea

Question 27

Besides Coxsackie A, B, and echoviruses, what other organisms can cause Pericarditis? (5 more)

Answer 27

``` Staph aureus strep pneumo Haemophilus influenzae Neisseria meningitidis Influenza virus ```

Question 28

Most likely causative agent of IV catheter-related infections?

Answer 28

staph aureus

Question 29

What is the predominant infectious agent during the initial year following prosthetic valve surgery?

Answer 29

Staph epidermidis

Question 30

What is the most likely organism to infect a prosthetic valve more than 1 year after the surgery?

Answer 30

Strep viridans

Question 31

What do you see clinically in a patient with valvular infection?

Answer 31

Fever as part of an associated endocarditis | Heart murmur

Question 32

After implantation of a pacemaker of defibrillator, what is the most common infection within 2 weeks of the implantation?

Answer 32

Staph aureus

Question 33

After pacemaker/defibrillator implantation, what is the most common infection 2 weeks-1 year after implantation?

Answer 33

Staph epidermidis

Question 34

One year after pacemaker/defibrillator implantation-what bug predominates infection?

Answer 34

Strep Viridans

Question 35

Besides staph aureus, staph epidermidis, and strep viridans, what other bug can cause infection after defibrillator or pacemaker implantation?

Answer 35

Enterococci species

Question 36

How long does it take the clinical signs of RMSF to appear after infection?

Answer 36

1-2 weeks

Question 37

In RMSF, what causes the petechial rash?

Answer 37

Rickettsia attach and are engulfed into epithelial cells-->multiply and spread to nearby cells-->replication casues RBC leakage