Gram negative cocci

Question 1

what are the gram negative cocci?

Answer 1

• Neisseria
• Moraxella
• Acinetobacter

Question 2

Nisseria

Question 3

what are the medical imp. Species of nisseria?

Answer 3

• Neisseria meningitidis
• Neisseria gonorrhoeae

Question 4

what is the biology of Neisseria meningitidis?

Answer 4

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

Question 5

where can we find neisseria meningitidis?

Answer 5

Human nasopharynx

Question 6

how does neisseria meningitidis spread?

Answer 6

INHALATION respiratory droplets

Question 7

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

Answer 7

2 – 18 yrs *

Question 8

what are the virulence factors for Meningococcal meningitis?

Answer 8

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

Question 9

what is another name for neisseria meningitidis?

Answer 9

Meningococcal meningitis

Question 10

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

Answer 10

Polysaccharide capsule

Question 11

what is the virulence factor that Promotes colonization of oropharynx?

Answer 11

IgA protease

Question 12

give an example of an endotoxin in meningococcus?

Answer 12

Lipooligosaccharide (LOS)

Question 13

what does Lipooligosaccharide (LOS) cause?

Answer 13

Endotoxic shock (septic shock)

Question 14

what are the Risk factors for severe infection with meningococcus?

Answer 14

• complement deficiency (C5-C8)
• Asplenia

Question 15

what are the predisposing factors for meningococcus?

Answer 15

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

Question 16

what Age groups affected* with meningococcus?

Answer 16

• Adolescents/young adults (Outbreaks in institutions, schools, military barracks, dormitories *)
• In USA – infants less than 1 yr (highest incidence)

Question 17

what will meningococcus cause?

Answer 17

meningitis

Question 18

what symptoms are seen in meningitis with meningococcal infection?

Answer 18

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

Question 19

how do you call infection of meningococcus in the blood?

Answer 19

Meningococcemia

Question 20

what symptoms are seen in meningococcemia?

Answer 20

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

Question 21

what is Waterhouse-Friderichsen syndrome *?

Answer 21

Bilateral adrenal hemorrhage & acute adrenal gland insufficiency *

Question 22

what symptoms are seen in Waterhouse-Friderichsen syndrome *?

Answer 22

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

Question 23

how do you diagnose N. meningitidis?

Answer 23

• 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

Question 24

how do you treat N. meningitidis?

Answer 24

Ampicillin/Penicillin G

Question 25

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

Answer 25

Ceftriaxone

Question 26

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

Answer 26

prophylaxis – rifampin or ciprofloxacin

Question 27

what is the vaccine against N. meningitidis?

what does the vaccine use?

Answer 27

Conjugate meningococcal vaccine (MCV4) *

capsular polysaccharides

Question 28

the CDC recommends to be vaccinated at what age?

a booster dose should be given at what age?

Answer 28

11-12 year olds

booster = 16 y/o*