Bordetella pertussis

Question 1

Characteristics of B. pertussis?

Answer 1

• extremely small
• Gram (-)
• Coccobacilli
• Obligate aerobes
• non motile

Question 2

What is the medium required for isolation from direct cough plates or nasopharyngeal cultures for B. pertussis

Answer 2

Regan Lowe Media (charcoal added)

Question 3

What is the major manifestation of B. pertussis?

Answer 3

Whooping Cough

Question 4

What is the mechanism of action of Pertussis toxin (PXT)?

Answer 4

Over activates adenylate cyclase by disabling Gi. and leads to excessive mucous production

Question 5

What is the manifestation of Whooping cough?

Answer 5

Child coughs on expiration and “whoops” on inspiration

Question 6

B. pertussis can cause the following clinical diseases?

Answer 6

• Subconjunctival hemorrhage
• Facial & truncal petechiae
• Hernias

Question 7

What stage of B. pertussis lasts 2-4 weeks and has repetitive coughs with whoops and vomiting?

Answer 7

Paroxysmal stage

Question 8

What are the VF’s B. pertussis uses for attachment?

Answer 8

• FHA (fhaB)
• Fimbriae (fimD)
• Pertactin

Question 9

What are the toxins B. pertussis releases?

Answer 9

• Tracheal CytoToxin (TCT)
• Pertussis Toxin (PTX)
• Adenylate cyclase toxin (ACT)

Question 10

how does tracheal cytotoxin work?

Answer 10

its an exotoxin that inhibits DNA synthesis in epithelial cells

Question 11

How does Adenylate cyclase toxin (ACT) work?

Answer 11

Binds to Adenylate cyclase, leads to unresponsive IL-8 receptor and C5a receptor and leads to lymphocytosis

Question 12

What kind of colonies does B. pertussis produce on a blood agar?

Answer 12

Small, shiny, mercury like colonies

Question 13

What are the 3 stages of B. pertussis?

Answer 13

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

Question 14

What vaccine can you use to prevent B. pertussis?

Answer 14

DTaP
(diphtheria, tetanus, Pertussis)
- includes strains of pertactin, FHA and fimbriae

Question 15

What is the treatment of choice for Bordetella?

Answer 15

Macrolides OR AUGMENTIN (amoxicillin + clavulanate)