Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology test 2 > Otitis, sinusitis, diphtheria, pertussis > Flashcards

Otitis, sinusitis, diphtheria, pertussis Flashcards

1
Q

Inflammation of the external auditory canal

A

otitis externa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is a major predisposing factor for otitis externa

A

moisture (swimmer’s ear)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the most common causes of otitis externa

A
  • pseudomonas aeruginosa
  • staphylococcus aureus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

pseudomonas aeruginosa

  • gram status
  • shape
  • form capsule?
A
  • gram negative
  • bacilli
  • encapsulated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

pseudomonas aeruginosa produces what pigments

A
  • pyocyanin: non-fluorescent bluish
    • many strains produce
  • pyoverdin: fluorescent green
    • nearly all strains produce
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what function enables pseudomonas aeruginosa to produce pyocyanin and pyoverdin

A
  • pyocyanin: generates ROS
  • pyoverdin: sequesters iron (a siderophore)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

staphylococcus aureus

  • gram status
  • shape
  • capsule?
A
  • gram positive
  • cocci in clusters
  • encapsulated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

staphylococcus aureus: coagulase positive or negative

A

positive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

staphylococcus aureus: what happens when it is put on blood agar

A

B-hemolytic: the area appears lightened (yellow) and transparent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

how is otitis externa diagnosed

A
  • examination of ear
  • gram stain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

treatment of otitis externa

A
  • topical
    • acidifying agents
    • topical corticosteroids
  • oral abx if fever is present
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are the mot common bacterial causes of otitis media and sinusitis

A
  • streptococcus pneumoniae (50%)
  • haemophilus influenzae (20%)
  • moraxella catarrhais (10%)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

inflammation of the middle ear, including tympanic membrane and usually associated with a buildup of fluid in the middle ear space

A

otitis media

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

steptococcus pneuomonia

  • gram status
  • shape
  • capsule?
A
  • gram positive
  • lancet-shaped diplococci
  • virulent strains are encapsulated
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

steptococcus pneuomonia has what two distinguishing factors on blood agar

A
  • a-hemolysis
  • sensitive to optochin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Haemophilus influenzae

  • gram status
  • shape
A
  • gram negative
  • coccobacilli
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

moraxella catarrhalis

  • gram status
  • shape
A
  • gram negative
  • diplococci
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

moraxella catarrhalis has what distinguishing factors

A
  • oxidase positive
  • B-lactamase producer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

diagnosis of otitis media

A

clinical presentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

DOC for acute bacterial otitis media

A
  • amoxicillin
  • chronic: tympanostomy tubes may be inserted
21
Q

diagnosis of sinusitis

A
  • clinical presentation and history
  • CT scan?
22
Q

causative agent of diphtheria

A

corynebacterium

23
Q

corynebacterium

  • gram status
  • shape
  • requires oxygen?
A
  • gram positive
  • pleomorphic bacilli
  • grows aerobically on blood agar
24
Q

which bacteria has a “Palisades,” “V,” “Chinese letters” appearance

A

corynebacterium

25
Q

what toxin does corynebacterium have

A

diphtheria toxin

26
Q

diphtheria toxin is what type of toxin

A
  • A-B exotoxin
    • B: binding
    • A: catalytic
27
Q

diphtheria toxin MOA

A
  • exotoxin binds to a heparin-binding EGF receptor
    • exotoxin is endocytosed and releases the A subunit
  • A subunit inactivates EF-2 via ADP-ribosylation, halting protein synthesis
28
Q

what are the two types of diphtheria

A
  • cutaneous
  • respiratory
29
Q

what is cutaneous diphtheria

A
  • chronic, nonhealing sores or ulcers
  • most cases are due to nontoxigenic strains
30
Q

presentation

  • pharyngeal colonization
  • sudden onset of malaise, exudative pharyngitis, low grade fever and lymphadenitis
  • formation of pseudomembrane
  • “bull neck” in serious disease
A

respiratory diphtheria

31
Q

what is the pseudomembrane of respiratory diphtheria consist of

A
  • network of fibrin + bacteria + WBC + necrotic epithelial cells
32
Q

how is diphtheria transfered

A

person to person via respiratory droplets or skin contact

33
Q

where is diphtheria found

A
  • worldwide, but uncommon is developed countries
  • vaccine use
34
Q

how is diphtheria diagnosed

A
  • clinical examination
    • pseudomembrane
    • bull neck
35
Q

what cultures are used to diagnose diphtheria

A
  • Loeffler’s medium: supports growth and enhances formation of volutin granules
  • cysteine-tellurite agar: tests toxin production
36
Q

diptheria

  • gram status
  • shape
  • volutin
A
  • gram positive
  • bacilli
  • metachromatic (volutin) granules
37
Q

what tests are used to diagnose diphtheria

A
  • detect toxin production
    • Elek test
    • PCR
    • ELISA
    • immunochromatographic strip assay
38
Q

treatment of diphtheria

A
  1. neutralize exotoxin : diphtheria antitoxin
  2. Abx: DOC: erythromycin
  • prevention: vaccine
    • DTap, Tdap, Td
39
Q

what is the causative agent of whooping cough

A
  • pertussis: Bordetella pertussis
40
Q

Bordetella pertussis

  • gram status
  • shape
  • require oxygen?
A
  • gram negative
  • coccobacilli
  • grows aerobically on enriched agar
41
Q

What adhesins does Bordetella pertussis have

A
  • filamentous hemagglutinin
  • agglutinogens
42
Q

Bordetella pertussis has what four exotoxins. what is the major one

A
  • pertussis toxin :A-B exotoxin
  • adenylate cyclase toxin
  • dermonecrotic toxin
  • tracheal cytotoxin
43
Q

describe the catarrhal stage of pertussis disease

A
  • inflammation of mucus membranes
  • presents as nonspecific URI
  • highly contagious
44
Q

describe the paroxysmal stage of pertussis disease

A
  • paroxysmal coughing, often followed by vomiting “Whoop” (50/day)
  • 2-4 weeks
  • complications due to vomiting and increased pressure
45
Q

describe the convalescent stage of pertussis disease

A
  • recovery
  • paroxysms decrease in number and severity
  • complications
    • PNA
46
Q

pertussis affects what species

A

strictly a human disease

  • highest incidence: children < 1 yo
47
Q

pertussis is diagnosed using what cultures

A
  • bordet-gengou agar
  • regan-lowe agar
48
Q

treatment of pertussis

A

DOC: erythromycin

  • prevention: immunization
    • DTap (series); Tdap (booster)
      • contain inactivated pertussis toxin and 1+ bacterial adhesins

Microbiology test 2 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions