Gram Negative Bacteria

Question 1

List 2 types of gram negative cocci.

What structure do they have?

Answer 1

Neisseria
Moraxella

Diplococci

Question 2

List 2 types of neisseria.

Which diseases do they cause?

Answer 2

N. meningitides (meningitis, bacteraemia)

N. gonorrhoea (gonorrhoea)

Question 3

Which 5 conditions can N. gonorrhoea cause? Consider conditions in men, women and neonates.

Answer 3

Urethritis (men)
PID (women)
Septic arthritis
Bacteraemia
Ophthalmia neonatorum

Question 4

Describe the virulence factors of N. meningitides. (3)

Answer 4

1. Have a capsule containing different serotypes (A, B, C)
2. Expresses endotoxins, causing vascular necrosis and haemorrhage into the skin
   - Causes classic non-blanching rash
3. Contains IgA1 protease

Question 5

List 5 types of gram negative bacilli.

Answer 5

Coliforms
Pseudomonas
Coccobacilli
Curved bacilli
Spirochetes

Question 6

What are the 2 categories of coliform bacteria?

List some examples of each.

Answer 6

LACTOSE FERMENTING COLIFORMS:
E. coli
Enterobacter
Klebsiella

NON-LACTOSE FERMENTING COLIFORMS:
Proteus
Serratia
Shigella
Salmonella

Question 7

Which 5 conditions can E. coli cause?

Answer 7

UTIs
Pneumonia
Intra-abdominal infection
Bacteraemia
Meningitis

Question 8

List 3 types of E. coli, and state which disease they cause.

Answer 8

Enterotoxigenic E. coli (cholera-like illness)

Enteropathogenic E. coli (infantile gastroenteritis)

Verocytotoxin producing E. coli (VTEC) (haemolytic uraemic syndrome, thrombotic thrombocytopenic purpura)

Question 9

Which 3 conditions can be caused by enterobacter, klebsiella or serratia?

Answer 9

Pneumonia
UTIs
Wound infections

Question 10

Which condition can proteus cause?

What does this suggest about disease severity?

Answer 10

UTIs

Rarely severe

Question 11

List 4 examples of shigella bacteria.

Answer 11

S. sonnei
S. boydii
S. dysenteriae
S. flexneri

Question 12

Which condition does shigella cause? List 3 clinical features.

Answer 12

Gastroenteritis

Fever
Cramps
Diarrhoea (blood and mucous)

Question 13

List 2 examples of salmonella. State which diseases they cause.

Answer 13

S. typhi (typhoid)

S. paratyphi (typhoid)

Question 14

Which 3 conditions can be caused by salmonella?

Answer 14

Diarrhoea
Typhoid
Osteomyelitis

Question 15

Which 2 conditions can pseudomonas aeruginosa cause?

In which patient groups does this happen?

Answer 15

Colonisation in other sites, e.g. leg ulcers
Infection in specific patient groups

Burns patients
CF
Bronchiectasis
UTIs

Question 16

List 3 types of bacteria commonly associated with pseudomonas.

Answer 16

Burkolderia cepacia
Stenotrophomonas maltophilia
Acinetobacter

Question 17

List 2 examples of small coccobacilli.

Answer 17

Haemophilus influenzae

Legionella pneumophilia

Question 18

Which 4 conditions can haemophilus influenzae cause?

Answer 18

Epiglottitis
Meningitis
Lower respiratory tract infections
Otitis media

Question 19

List 3 examples of curved gram negative bacteria. State which diseases they cause.

Answer 19

Campylobacter (abdominal pain, bloody diarrhoea)

Helicobacter (PUD)

Vibrio cholera (watery diarrhoea)

Question 20

List 3 examples of spirochetes. State which diseases they cause.

Answer 20

Treponema pallidum (syphilis)

Borrelia burgdorferi (Lyme disease)

Leptospira (leptospirosis)