Specific bacterial infections

Question 1

What usually accompanies meningococcal septicaemia?

Answer 1

Purpuric rash which may start anywhere on body and then spread.

(characteristic lesion = non-blanching, irregular in size and outline and have necrotic centre.)

Question 2

Where is strep. pneumoniae often found?

Answer 2

In nasopharynx of healthy children

Question 3

What diseases can pneumococcal infection cause?

Answer 3

• Pharyngitis
• Otitis media
• Conjunctivitis
• Sinusitis
• Invasive disease (Pneumonia, sepsis, meningitis)

Question 4

What has decreased the incidence of invasive disease caused by pneumococcal infection?

Answer 4

13-valent pneumococcal vaccine included in standard immunisations.

Question 5

Who should be given prophylactic penicillin to prevent pneumococcal infection?

Answer 5

Children at increased risk of infection - immunosuppressed or Hyposplenism

Question 6

What important causes of systemic infection has decreased due to immunisations?

Answer 6

Haemophilus influenzae b

Pneumococcal infection

Question 7

What organisms can cause disease using ‘superantigen’ and how does this happen?

Answer 7

Staphylococci and group A strep.

Release toxins which act as ‘superantigen’ - bind to part of T-cell receptor shared by many T cells - stimulates massive T cell proliferation and cytokine release.

Question 8

What type of bacteria is neisseria meningitidis?

Answer 8

Gram negative diplococcus

Question 9

What type of bacteria is strep pneumoniae?

Answer 9

Grame positive, alpha-haemolytic, anaerobic, lancet-shaped diplococci.

Question 10

What type of bacteria is h. influenzae?

Answer 10

Gram negative coccobacillus (between cocci and bacilli)

Question 11

What type of bacteria is staphylococcus?

Answer 11

Gram positive cocci (form clusters)