Classification of pathogenic bacteria - Gram positive

Question 1

Cocci

Answer 1

Staphylococci and streptococci

Question 2

Staphylococci

Answer 2

Clusters

Question 3

Streptococci

Answer 3

Chains

Question 4

Coagulase test positive

Answer 4

Staphylococcus aureus - MSSA MRSA

Question 5

Coagulase test negative

Answer 5

Skin commensals which can be pathogenic in contact with foreign body/ prostheses

Question 6

Staphylococcus Aureus

Answer 6

Commensal carried in nose
Septicaemia, boils
Penicillin resistant ( beta lactamase production)

Question 7

Alpha haemolytic

Answer 7

Partial haemolysis
Blood agar green
Streptococcus pneumonia
Veridans streptococci - oral flora cause endocarditis

Question 8

Beta haemolytic

Answer 8

Groups A-G identified using Lancefield grouping but A,B + D most scientifically important
Tur blood agar clear and are completely haemolytic

Question 9

Group A

Answer 9

Streptococcus pyogenes - necrotising fasciitis and cellulitis

Question 10

Group B

Answer 10

Streptococcus agalactiae - neonatal sepsis, genital tract carriage

Question 11

Group D

Answer 11

Enterococci and are non haemolytic - UTI

Question 12

Clostridium difficile

Answer 12

• Increased risk with antibiotic use and spreads through spores
• detected using antigen detection in stool with ELISA
• pseudomembranous collitis

Question 13

Clostridium perfingens

Answer 13

Found in soil and responsible for gas gangrene

Question 14

Clostridium tetani

Answer 14

Toxins cause tetanus

Question 15

Clostridium botulinum

Answer 15

Botox

Question 16

Bacilus Anthracis

Answer 16

Cause anthrax