2.5

Question 1

strep pneumoniae morphology

Answer 1

• Diplococci with pointed ends

Question 2

strep pneumoniae commensals of

Answer 2

• Commensals of the oropharynx in some individuals

Question 3

strep pneumoniae virulence factor

Answer 3

• Polysaccharide capsule - virulence factor
  ○ Provides bacteria with protection against phagocytosis by cells of the human immune system
  ○ Immunogenic feature

Question 4

serotypes of strep pneumoniae

Answer 4

• 60-80% of invasive pneumococcal; infections caused by a small number of serotypes: 6, 14, 18, 19, 23
  ○ Serotypes causing disease will differ between geographical areas, age groups and risk factors
  ○ Typing antisera
  § Monoclonal antibodies raised in rabbits, directed against individual capsular types

Question 5

vaccines for strep pneumoniae

Answer 5

• Vaccines
  ○ Immunological protection against particular high risk pneumococcal strains
  § 10, 13 and 23 valent vaccine
  ○ Recommended for those members of the community recognised as having risk factors for invasive pneumococcal disease

Question 6

strep pneumonie invasive disease clinical features

Answer 6

§ Bacteraemia
□ Most common form of invasive disease
□ May occur alone or with pneumonia or meningitis
§ Septicaemia
§ haematogenous spread
§ Meningitis
□ S pneumoniae is the most common cause of bacterial meningitis
□ In the developed world, most likely cause is Neisseria meningitidis
□ High mortality and high incidence of neurological deficits in survivors
§ Endocarditis

Question 7

strep pneumoniae non invasive disease clinical futures

Answer 7

direct spread from oropharynx 
			§ Conjunctivitis 
			§ Otitis media 
			§ Sinusitis 
			§ Pneumonia
				□ S pneumoniae is the most common cause of community acquired pneumonia worldwide 
			§ bronchitis

Question 8

2 species of enterococcus

Answer 8

• Two species of clinical importance
  ○ Enterococcus faecalis
  ○ Enterococcus faecium

Question 9

enterococcus commensal of

Answer 9

• May be found in the bowel as part of commensal flora

Question 10

enterococcus types with

Answer 10

group D

Question 11

clinical features of enterococcus infection

Answer 11

nosocomial infections in debilitated hosts, bacteraemia, UTI, endocarditis,
○ Other enterococcal infections include
§ Intra-abdominal infections
§ Pelvic infections
§ Wound infections
§ Meningitis

Question 12

enterococcus clinical features of nosocomial infections

Answer 12

○ Nosocomial infections in debilitated hosts

§ F faecalis more commonly encountered than E faecium

Question 13

enterococcus bacteraemia clinical features

Answer 13

○ Bacteraemia

§ Particularly nosocomial, associated with infected intravascular catheters

Question 14

resistance to enterocci

Answer 14

• Resistance
  ○ More of an issue with E faecium than E faecalis
  ○ E faecium becoming resistant to vancomycin which used to be a last line of defence
  § Called VRE - Vancomycin Resistant Enterococci

Question 15

enterococci resistant to vancomycin

Answer 15

§ Called VRE - Vancomycin Resistant Enterococci