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Flashcards in Gram negative cocci Deck (28):
1

what are the gram negative cocci?

  • Neisseria
  • Moraxella
  • Acinetobacter

2

Nisseria

3

what are the medical imp. Species of nisseria?

  • Neisseria meningitidis
  • Neisseria gonorrhoeae

4

what is the biology of Neisseria meningitidis?

  • Encapsulated gram negative diplococcus *
  • Oxidase + , catalase + *
  • Breaks down maltose & glucose (MeningoCoccos) *

5

where can we find neisseria meningitidis?

Human nasopharynx

6

how does neisseria meningitidis spread?

INHALATION respiratory droplets

7

neisseria meningitidis is the most common cause of  meningitis in what  in age group?

 

 2 – 18 yrs *

8

what are the virulence factors for Meningococcal meningitis?

  1. Polysaccharide capsule 
  2. IgA protease
  3. Endotoxin
  4. Risk factors for severe infection: 

9

what is another name for neisseria meningitidis?

Meningococcal meningitis

10

what is the virulence factor that acts as Antiphagocytic, antigenic?

Polysaccharide capsule 

 

11

what is the virulence factor that Promotes colonization of oropharynx?

IgA protease

 

12

give an example of an endotoxin in meningococcus?

Lipooligosaccharide (LOS) 

13

what does Lipooligosaccharide (LOS) cause?

 Endotoxic shock (septic shock)

14

what are the Risk factors for severe infection with meningococcus?

  • complement deficiency (C5-C8)
  • Asplenia

15

what are the  predisposing factors for meningococcus?

  • Recent antecedent viral resp. tract infection
  • Smoking (active/passive)

16

what Age groups affected* with meningococcus?

 

- Adolescents/young adults (Outbreaks in institutions, schools, military barracks, dormitories *)

- In USA – infants less than 1 yr (highest incidence)

 

17

what will meningococcus cause?

meningitis

18

what symptoms are seen in meningitis with meningococcal infection?

  • High fever (rapid onset)
  • Nuchal rigidity (stiff neck)
  •  Photophobia (sensitivity to light), confusion, headache, vomitting
  • Petechia (purpural rash) *
  • Rapidly fatal 

19

how do you call infection of meningococcus in the blood?

Meningococcemia

20

what symptoms are seen in meningococcemia?

  • Thrombosis
  • Disseminated intravascular coagulation
  • Petechiae (small hemorrhages under the skin)*
  • Septic shock

21

what is Waterhouse-Friderichsen syndrome *?

Bilateral adrenal hemorrhage & acute adrenal gland insufficiency *

 

22

what symptoms are seen in Waterhouse-Friderichsen syndrome *?

  • Ecchymoses (large purple skin haemorrhages)
  • DIC (disseminated intravascular coagulation)
  • Hypotension & Shock
  • Uncommon condition but fatal

23

how do you diagnose N. meningitidis?

  • Gram stain CSF *  (Numerous PMNs & GN diplococci *)
  • culture in Blood agar with 5-10% CO2 (capnophilic) *
  • Sugar utilization: Maltose & Glucose (MeninGococcus) * (increased protein, decreased sugar *)
  • CSF Bacterial Antigen detection *
  • Detects capsular antigen, rapid test 

 

24

how do you treat N. meningitidis?

Ampicillin/Penicillin G

 

25

what if there is drug resistance to ampicillin/penicillin G?

Ceftriaxone

26

All close contacts with N. meningitidis should be given what?

prophylaxis – rifampin or ciprofloxacin

 

27

what is the vaccine against N. meningitidis?

what does the vaccine use?

Conjugate meningococcal vaccine (MCV4) *

capsular polysaccharides

28

the CDC recommends to be vaccinated at what age?

a booster dose should be given at what age?

 

11-12 year olds

booster = 16 y/o*