Gram Negative Cocci - Neisseria Species (Meningitidis, Gonorrhea)

Question 1

Characterize (4): Neisseria spp.

Answer 1

1. Gram - DIplococci
2. Oxidase +
3. Fimbriae
4. IgA protease

(Also catalase +)

Question 2

Name 2 culture mediums used for Neisseria spp.

Answer 2

1. Chocolate Agar

2. Thayer Martin

Question 3

What antibiotics is Thayer-Martin agar enriched with?

Answer 3

1. Vancomycin
2. Polymyxin
3. Nystatin

Question 4

Name an immunodeficiency which is associated with increased susceptibility to Neisseria spp.

Answer 4

C5-C9 deficiency

Unable to form MAC complex

Question 5

Why is Neisseria spp. so effective at evading the immune system?

Answer 5

Antigenic variation 
(Of the pili. Also IgA protease)

Question 6

Name 2 organisms with IgA proteases

Answer 6

1. Neisseria spp.

2. Strep. Pneumoniae

Question 7

Which species of Neisseria ferments maltose?

Answer 7

N. Meningitidis

Question 8

What is the first place N. Meningitidis colonizes ?

Answer 8

Nasopharynx

Question 9

Which strain of N. Meningitidis most commonly causes meningitis?

Answer 9

Type B

Question 10

Differentiate between the vaccine for H. Influenzae and N. Meningitidis in regards to the contained capsular antigen

Answer 10

1. H. Influenzae: contains Type B capsular antigen

2. N. meningitidis: does not contain type B capsular antigen

Question 11

Name 2 genetic defects which increase your risk for N. Meningitidis

Answer 11

1. C5-C9 deficiencies

2. Sickle cell and Asplenia patients

Question 12

What organism has LOS instead of LPS?

Answer 12

N. Meningitidis

LOS envelope proteins cause inflammatory response

Question 13

Describe the pathogenesis of Waterhouse-Friderichsen syndrome

Answer 13

LOS induced inflammation 
—> increased vascular permeability 
—> increased exudation 
—> decreased perfusion 
—> Reflexive vasoconstriction 
—> ischemic adrenals

Question 14

What organism is most associated with meningitis with petechial rash?

Answer 14

N. Meningitidis

Question 15

What is Waterhouse-Friderichsen syndrome?

Answer 15

Sepsis —> hemorrhage of adrenals

Question 16

Treatment : N. Meningitidis

Answer 16

Ceftriaxone

Question 17

Prophylaxis: N. Meningitidis

Answer 17

Rifampin

For close contact - someone who spent more than 8 hours with patient in 7 days prior to the onset of symptoms

Question 18

Which Neisseria species is facilitating intracellular ?

Answer 18

N. Gonorrhea

In PMN’s

Question 19

Which Neisseria Species is encapsulated

Answer 19

N. Meningitidis

Polysaccharide capsule inhibits phagocytosis

Question 20

Name 4 possible séqueles of untreated gonorrhea

Answer 20

Women:

1. Pelvic inflammatory disease
2. Fits-Hugh Curtis syndrome
3. Transmission to newborn

In men and women:
4. Asymmetric arthritis

Question 21

Describe the discharge of Gonorrhea

Answer 21

“White purulent discharge”

Question 22

What buzz word is associated with Fitz-Hugh-Curtis Syndrome?

Answer 22

“Violin string” adhesions

Question 23

What joint is most commonly affected by gonococcal septic arthritis?

Answer 23

Knee

Question 24

How can you differentiate neonatal conjuntivitis due to gonorrhea from chlamydia?

Answer 24

1. Gonorrhea: early onset

2. Chlamydia: Later onset

Question 25

Treatment: N. gonorrhea

Answer 25

Ceftriaxone + Azithromycin/Doxycicline