Gram negative Diplococci and Coccoid Rods

Question 1

What two bacteria are gram negative diplocci?

Answer 1

Neisseria meningococci and gonococci. Both ferment glucose, both produce IgA protease.

Question 2

How can they be differentiated?

Answer 2

Meningo = maltose fermenter.

Question 3

Which neisseria is often intracellular, within neutrophils?

Answer 3

Gonorrhea.

Question 4

Which neisseria has a polysaccharide capsule?

Answer 4

Meningococci.

Question 5

Which neisseria can be vaccinated against?

Answer 5

Meningococci.

Question 6

Why can’t one of the neisseria be vaccinated against?

Answer 6

Pilus proteins have high level of antigenic variation.

Question 7

How is N. gono transmitted?

Answer 7

sexually or perinatally

Question 8

How is N. meningo transmitted?

Answer 8

Respiratory/oral secretions.

Question 9

What is the disease presentation associated with N. gono?

Answer 9

Gonorrhea, septic arthritis, PID, Fitz-Hugh Curtis

Neonatal conjunctivitis

Question 10

What is the disease presentation associated with N. meningo?

Answer 10

Meningococcemia and meningitis

Waterhouse-Friderichsen syndrome (adrenal hemorrhage).

Question 11

What prevents N. gono disease?

Answer 11

Condoms decrease sexual transmission.

Erythromycin ointment prevents neonatal transmission.

Question 12

What prevents N. meningo disease?

Answer 12

Rifampin, cipro, or ceftriaxone prophylaxis in close contacts

Question 13

What is the treatment for N. gono disease?

Answer 13

Ceftriaxone (+ azithro or doxy for chlam coinfection)

Question 14

What is the treatment for N. meningo disease?

Answer 14

Ceftriaxone, penicillin G.

Question 15

Which bacteria are gram negative coccobaccilary organisms?

Answer 15

H. influenza
Bordatella
Pasteurella
Brucella

Question 16

How is H. influenza transmitted?

Answer 16

Aerosol transmission.

Question 17

What does the H. influenza b. vaccine contain?

Answer 17

Type B capsular polysaccharide (polyribosyribitol phosphate) conjugated to diptheria toxoid or other protein. .

Question 18

when is Hib vaccine given?

Answer 18

Between 2 and 18 mos.

Question 19

Why didn’t the Hib cure all H. influenza infections?

Answer 19

Most infections caused by non-typeable strains.

Question 20

What special culture is H. flu grown on?

Answer 20

Chocolate agar, which contains factor V (NAD+) and X (hematin).

Question 21

How else can H. flu be grown?

Answer 21

With staph aureus, which provides factor V through hemolysis of RBCs.

Question 22

What disease does H. influenza cause?

Answer 22

haEMOPhilus.
E: epiglottitis
M: meningitis
O: otitis media
P: Pneumonia

Question 23

How are mucosal H. influenza infections treated?

Answer 23

Amoxicillin +/- clav.

Question 24

How is H. influenza meningitis treated?

Answer 24

Ceftriaxone, rifampin ppx for close contacts.

Question 25

What is the difference between H. influenza that cause meningitis, epiglottis, and those that cause otitis media and sinusitis?

Answer 25

Otitis media and sinusitis ones are not encapsulated.

Question 26

How is bordatella pertussis transmitted?

Answer 26

Respiratory route

Question 27

What virulence factors does bordatella have?

Answer 27

``` Capsule, betalactamase Filamentous hemagglutin (FHA), pili rod that enables bac to bind to ciliated epithelial cells of bronchi ```

Question 28

How does pertussis toxin work?

Answer 28

1. Activates G proteins that increase cAMP - inc histamine sens, insulin release, lymphs 2. Extracytoplasmic adenylate cyclase - weaks neuts, lymphos 3. FHA for attachment. 4. Tracheal cytotoxin kills ciliated cells

Question 29

What are the three stags of Whooping cough?

Answer 29

1. Catarrhal phase 2. Paroxysmal phase 3. Convalescent stage

Question 30

What characterizes the catarrhal phase of whooping cough?

Answer 30

1-2 weeks, pt highly contagious Low grade fever, runny nose, mild cough Abx susceptible

Question 31

What characterizes the paroxysmal phase of whooping cough?

Answer 31

2-10 weeks Whooping non-productive cough Increased # of lymphos Abx ineffective

Question 32

What is the vaccine for bordatella?

Answer 32

DaPT: diphtheria, acellular Pertusssis, and Tetanus. Given at 2,4,6,15 mos, and between 4-6 yrs.

Question 33

What abx is useful in the catarrhal phase of bordatella?

Answer 33

erythromycin

Question 34

What special medium does bordatella grow in?

Answer 34

Bordet-Gangou: potatoes, blood, and glycerol + PCN.

Question 35

What two gram neg coccoids are also zoonotics?

Answer 35

Pasteurella (cat and dog bites) and brucella (unpasteurized dairy)

Question 36

What are the sx of pasteurella?

Answer 36

Cellulitis, osteomyelitis.

Question 37

What are the sx of brucellosis?

Answer 37

Undulant fever.