Staph & Strep

Question 1

What does the catalase test detect the presence of?

Answer 1

Catalase enzyme in aerobic organisms

Question 2

What can the catalase test differentiate?

Answer 2

Staphylococci from streptococci and helps to confirm gram stain observations

Question 3

What are the two recognised stphylococci used of medical importance?

Answer 3

Staphylococcus aureus
Staphylococcus epidermidis

Question 4

Are staphylococci pathogenic?

Answer 4

Not always they are a normal part of the flora of URTI and skin

Question 5

how to differentiate the two staphylococci?

Answer 5

A diagnosis on manitol salts agar
S.aureus ferments mannitol, creating acid, changing pH, changes from yellow to red

Question 6

How is S. aureus disease transmitted?

Answer 6

Touch from an infected but asymptomatic person to a susceptible individual
Also from contaminated food

Question 7

What is S. aureus caused by?

Answer 7

Acne, boils, pimples, pneumonia, carditic, meningitis

Question 8

Are most staphylococcal infections pus forming?

Answer 8

Yes

Question 9

Is alpha toxin hemolysin from S. aureus pore forming?

Answer 9

Yes

Question 10

What does hemolysin do when infected?

Answer 10

Lyses red blood cells by inserting into their membrane and forming a hole
Host cell contents leak

Question 11

What does S. aureus produce?

Answer 11

Coagulase, a tissue destroying enzyme

Question 12

What is the coagulase test?

Answer 12

Test to see if an organism converts fibrin to fibrinogen

Question 13

What is S. aureus leucocidin?

Answer 13

Another toxin that seperates the components that cats together to damage membranes

Question 14

What does S. aureus leucocidin target?

Answer 14

White bloods cells
Attcking against the immune system

Question 15

What is toxic shock syndrome?

Answer 15

A complication of S . aureus infection

Question 16

What are the symptoms of toxic shock?

Answer 16

High fever
Rash
Vomiting
Diarroea
Death

Question 17

What is the cause of toxic shock?

Answer 17

The use of highly absobant tampons

Question 18

What is a treatment of S. aureus?

Answer 18

Penicillin and cephalosporin

Question 19

How do the treatments work?

Answer 19

Inhibit bacterial cell wall biosynthesis and prevent cross-linking in the peptidoglycan layer

Question 20

What is beta-lactamases?

Answer 20

Enzymes produced by bacteria
(mechanism of resistance)

Question 21

What does MRSA stand for?

Answer 21

Methicillin resistant staphylococcus aureus

Question 22

What is MRSA?

Answer 22

Infections that are resistant to many drugs

Question 23

How to prevent S. aureus infection?

Answer 23

Imposible to prevent
People carry it without knowing
Good hygiene
Avoiding contact
Keeping wounds covered

Question 24

What distance is the best fro pathogens to trnasmit?

Answer 24

Short distances

Question 25

Does stretococci and staphylococcus areus have a thin ot thick cell and does it dry easily?

Answer 25

They have thich cell walls and are more resistant to drying

Question 26

What are the symptoms of URTI?

Answer 26

Common cold Annoying but not life threatning

Question 27

What are the symptoms of LRTI?

Answer 27

problematic Bacterial / pneumonia Big issue for the immunocompromised or elderly

Question 28

What does URTI stand for?

Answer 28

Upper respiratory tract infection

Question 29

Is URTI streptococci gram positive and what is the shape?

Answer 29

Gram positive and spherical bacteria in chains not clusters

Question 30

What does streptococci commonly cause?

Answer 30

Strep throat

Question 31

How can streptococcus be differentiated from staphylococcus?

Answer 31

Gram stain arrangement Catalase test Blood agar homolysis

Question 32

What can stretococci also produce?

Answer 32

Homolysins

Question 33

What are homolysins?

Answer 33

Lysis of red blood cells

Question 34

What are the types of hemolysis?

Answer 34

Alpha Beta Gamma

Question 35

What is alpha haemolysis?

Answer 35

Partial or green haemolysis

Question 36

What is beta haemolysis?

Answer 36

Complete lysis of red blood cells

Question 37

What is gamma haemolysis?

Answer 37

Not showing typical alpha or beta haemolysis

Question 38

What is strep throat?

Answer 38

A bacterial infection of the throat, inflammation and pain, severe sore throat

Question 39

What do S. pyogenes produce in strep throat?

Answer 39

Hemolysin Lyses red blood cells which cause beta-hemolysis on blood agr pkates

Question 40

What are the symptoms of strep throat?

Answer 40

Enlarged tonsils Red spots on the palate Mild fever Generally feeling unwell Tender lymph nodes

Question 41

What are some treatments of strep throat?

Answer 41

Antibiotics

Question 42

How to diagnose strep throat?

Answer 42

Rapid antigen detection systems Culture in a blood agar plate

Question 43

What is scarlet fever?

Answer 43

Exotoxins from streptococcus acts as superantigens, causing host inflammation and tissue destruction

Question 44

What are the symptoms of scarlet fever?

Answer 44

A body wide infection Severe sore throat Fever Characteristic rash

Question 45

How is scarlet fever treated?

Answer 45

Antibiotics or can get better on its own

Question 46

What are the complications to strep throat?

Answer 46

Rheumatic fever

Question 47

Why is rheumatic fever bad?

Answer 47

The immune response to streptococcus infection can generate antibodies that cross react with human cells

Question 48

What are the symptoms of rheumatic fever?

Answer 48

Fever Painful and tender joints Red, hot or swollen joints Small, painess bumps beneath the skin Chest pain Heart murmur Fatigue Outbursts of unusual behaviour

Question 49

What is streptococcus pneumoniae?

Answer 49

An invasive lung disease

Question 50

What does streptococcus pneumoniae do?

Answer 50

When the aveoli, an inflammatory response is stimulated causing plasma, blood and white blood cells to fill the alveoli