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Flashcards in Classification of Pathogenic Bacteria Deck (79)
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1

How do bacteria reproduce

Mainly by binary fission

2

Is cocci rod shaped or circular

Circular

3

Is bacilli rod shaped or circular

Rod shaped

4

Is staphylococci in clusters or chains

Clusters

5

Is streptococci in clusters or chains

Chains

6

What does a positive coagulase test mean

Staphylococcus aureus is present which may indidicate MSSA or MRSA

7

What is Staphylococcus aureus

A major human pathogen carried in the nose, axilla and perineum

8

What can Staphlyococcus aureus cause

Wide range of diseases
Boils/abscesses
Soft tissue infections
Septicaemia
Osteomyelitis

9

What is Staphylococcus aureus commonly resistant to and why

Penicillin
Due to the production of penicillinase however using a different mechanism can produce strains which are methicillin resistant

10

What does a negative coagulase test indicate

Many different species such as:
S. epidemidis
S. haemolyticus
S. saprophyticus
S. lugdunenis

11

What are the categories of Streptococcus

α-haemolytic (partial haemolysis) which turns blood agar green
β-haemolytic (complete haemolysis) which turns blood agar clear
non haemolytic

12

Give an example of an α-haemolytic streptococci and what it can cause

Streptococcus pneumoniae which causes pneumonia, meningitis and septicaemia

13

How can β-haemolytic streptococci be further identified

Through carbohydrate surface antigens which are split into groups A-G

The clinically most important groups are A, B, F and D

14

How are gram positive bacilli able to grow

Aerobically
Anaerobically

15

Give an example of a group A streptococci

Streptococcus pyogenes which is a major pathogen causing pharyngitis, cellulitis and necrotising fasciitis (‘flesh eating bug’)

16

What is an important cause of diarrhoea that is which is associated with toxin production and can be potentially fatal

Clostridium difficile which is difficult to culture and asymptomatic when carried in the gut of healthly people

17

What increases the risk of obtaining Clostridium difficile

Antibiotics
Anything which disrupts the normal gut flora

18

How can Clostridium difficile spread

Spores

19

How is Clostridium difficile detected

Using its antigens and toxins in stool samples by ELISA.

20

Name 2 Gram negative cocci

Neisseriac spp.
Moraxella spp.

21

What is meningitis

Inflammation of the meninges and septicaemia

22

What does Neisseria meningitidis cause and how can it be identified

Meningitis which is the inflammation of the meninges and septicaemia.

PCR can be used on EDTA blood

23

What does Neisseria gonorrhoeae cause and how is it spread

Urethritis in men
Pelvic inflammation disease in women
Sexual contact

24

What does Moraxella catarrhalis act as the causative agent for

Respiratory tract infections especially in those with underlying lung pathology.

25

What are coliforms

Organisms which are in the Enterobacteriaceae family

26

Where are coliforms mainly found

Human large intestine

27

What is a useful test to identify Gram negative bacteria

Lactose fermentation is useful as a preliminary test

28

What are the virulance factors for E. coli

Pili
Capsule
Endotoxin
Exotoxins

29

Where can E. coli be found

Human and animal reservoirs

30

What does E. coli ferment

Lactose