lecture 31

Question 1

most common cause of laryngitis, tracheitis and epiglottitis

Answer 1

• viral

- larynx and trachea have non expandable rings so when theres inflammation =could cause asphyxiation

Question 2

Haemophilus influenza
type of bacteria 
what does it require for growth
how many capsular serotypes
capsule called

Answer 2

• gram negative, coccobacili
• requires hemin (Haem-ophilus) and NAD
• serotypes A-F -B being the most virulent
• capsule = PRP =used as vaccine target (remember PRP as in blood- haem)

Question 3

Haemophilus influenza type B

Answer 3

• worst one
• has PRP capsule
• causes conjunctivitis, sinusitis, otitis media, pneumonia, meningitis, purpuric fever, bacteriemia

Question 4

what are the three virulence factors in hemophilus influenza type B

Answer 4

• PRP capsule
• LPS
• IgA protease

Question 5

how is serotype B diagnosed? treated? mortality in untreated? prevention?

Answer 5

• gram staining
• serious- broad spectrum antibiotic
• less severe-amoxicillin
• if untreated >90% die
• prevention is via vaccine against PRP

Question 6

what typically causes ACUTE bacterial bronchitis? what are common symptoms

Answer 6

mycoplasma pneumoniae/ dry cough

Question 7

what causes bacterial bronchitis-whooping cough and what are the hallmark symptoms

Answer 7

bordetella pertussis

increase respiratory secretions but decrease in mucocilliary clearance causing hi pitched cough

Question 8

what kind of bacteria is whooping cough

Answer 8

bortatella pertussis is a gram negative coccobacilli

Question 9

how does bortatella pertussis infect

Answer 9

-it adheres to ciliated mucosa, multiplies and produces toxic factors

Question 10

what are the stages of whooping cough?

Answer 10

• incubation 7-10 days where you have rising virulence and no symptoms
• catarrhal stage- most virulent stage, 1-2 wks, rhinorrhea, malaise, fever, anorexia
• paroxysmal- 2-4 weeks, repetitive cough-WHOOPING, vomit, leukocytosis and lessening virulence
• covalescent- 3-4 wks longer, diminished cough and secondary complications like seizures

Question 11

virulence factors for whooping cough

Answer 11

• filamentous hemagluttinin- binds ciliated epithelial cells and produces pertussis toxin that increase adenylate cyclase and cAMP to increase respiratory secretions and cause cough
• LPS
• AB toxin

Question 12

treatment for whooping cough

Answer 12

macrolides- azithromycin and clarithomycin

Question 13

diagnosis and prevention of whooping cough

Answer 13

diagnosis- clinical (via cough), culture, PCR,

prevention DTaP with detoxified pertussis toxin