L9 Otitis, sinusitis, diptheria, pertussis

Question 1

causes of otitis externa

Answer 1

pseudomonas aeruginosa

staphylococcus aureus

Question 2

causes of otitis media/sinusitis

Answer 2

streptococcus pneumoniae (50%)
moraxella catarrhalis
haemophilus influenzae

Question 3

cause of diphtheria

Answer 3

corynebacterium diptheriae

Question 4

cause of whooping cough/pertussis

Answer 4

bordetella pertussis

Question 5

signs/symptoms of otitis externa

Answer 5

otalgia
otorrhea
fever

Question 6

predisposing factors to otitis externa

Answer 6

moisture, insertion of foreign objects, trauma, chronic skin diseases

Question 7

pseudomonas aeruginosa

Answer 7

G-
encapsulated
pigment producer

Question 8

pseudomonas aeruginosa produces pigments

Answer 8

pyocyanin: non-fluorescent blue
pyoverdin: fluorescent green

Question 9

pyocyanin

Answer 9

produced by many pseudomonas stains

generates reactive oxygen species

Question 10

pyoverdin

Answer 10

produced by all pseudomonas strains

sequesters iron

Question 11

something that sequesters iron

Answer 11

a siderophore

Question 12

staphylococcus aureus

Answer 12

G+
Cocci in clusters
Coagulase positive
B hemolytic

Question 13

bulging tympanic membrane due to pus in middle ear

Answer 13

acute otitis media

Question 14

streptococcus pneumoniae

Answer 14

G+
lancet shaped diplococci
virulent strains are encapsulated
alpha-hemolytic
sensitive to optochin

Question 15

beta hemolytic

Answer 15

staphylococcus aureus

Question 16

alpha hemolytic

Answer 16

streptococcus pneumoniae

Question 17

pseudomonas cause

Answer 17

otitis externa

Question 18

staph aureus causes

Answer 18

otitis externa

Question 19

strep pneumo causes

Answer 19

otitis media/sinusitis

Question 20

moraxella catarrhalis causes

Answer 20

otitis media/sinusitis

Question 21

haemophilus influenzae causes

Answer 21

otitis media/sinusitis

Question 22

haemophilus influenzae

Answer 22

G-
coccobacilli
some nontypeable strains

Question 23

moraxella catarrhalis

Answer 23

G-
diplococci
oxidase positive
Beta lactamase producer

Question 24

resistant to beta lactams due to beta lactamase

Answer 24

moraxella catarrhalis

Question 25

the only diplococci

Answer 25

moraxella catarrhalis

Question 26

who gets a typmanocentesis to culture/gram stain

Answer 26

restricted pt populations

Question 27

2 diseases that are diphtheria

Answer 27

cutaneous | diptheria/respiratory

Question 28

corynebacterium diptheriae

Answer 28

G+ pleomorphic bacilli with palisade shape metachromatic (volutin) granules grow aerobically on blood agar

Question 29

palisades

Answer 29

diptheriae have a V appearance

Question 30

diptheria toxin is a

Answer 30

phage encoded A-B exotoxin

Question 31

diptheria toxin binds to

Answer 31

heparin-binding EGF receptor

Question 32

The A subunit of diptheria toxin, once acidified and released within the vesicle and moving to the cytoplasm

Answer 32

inactivates EF-2 via ADP ribosylation, halting protein synthesis

Question 33

chronic nonhealing sores or ulcers

Answer 33

cutaneous diphtheria due to nontoxigenic strain

Question 34

bull neck

Answer 34

severe respiratory diphtheria

Question 35

pseudomembrane

Answer 35

respiratory diphtheria

Question 36

respiratory diphtheria colonizes

Answer 36

pharynx

Question 37

ssudden onset of malaise, exudative pharyngitis, low grade fever, LAD

Answer 37

respiratory diphtheria

Question 38

pseudomembranes are composed of

Answer 38

fibrin bacteria WBCs necrotic eptihelial cells

Question 39

systemic toxicity of respiratory diphtheria

Answer 39

myocarditis | demyelination

Question 40

diphtheria spread

Answer 40

asymptomatic carriers person-to-person via respiratory droplets or skin contact developing countries

Question 41

what can you culture diphtheria on

Answer 41

loeffler's medium | cystein-tellurite agar

Question 42

loeffler's medium

Answer 42

enhances formation of volutin granules in diptheria

Question 43

cystein-tellurite agar

Answer 43

diptheria grows a distinctive black color due to tellurite reduction, isolates are tested for toxin production

Question 44

volutin staining of diptheria

Answer 44

metachromatic (volutin) granules

Question 45

Tests for toxin production in diphtheria

Answer 45

Elek test PCR ELISA Immunochromatographic strip assay

Question 46

Elek test for diptheria toxin production

Answer 46

immunodiffusion assay to secretion of exotoxin

Question 47

PCR test for diptheria toxin production

Answer 47

detect tox gene

Question 48

ELISA test diptheria toxin production

Answer 48

detects the exotoxin

Question 49

Immunochromatographic strip assay test for diptheria toxin production

Answer 49

detects the exotoxin and is very sensitive

Question 50

Bordetella pertussis

Answer 50

``` G- small coccobacilli grows aerobically on enriched agar virulence factors adhesions, exotoxins endotoxin ```

Question 51

4 pertuiss exotoxins

Answer 51

Pertussis toxin Dermonecrotic toxin Tracheal cytotoxin Adenylate cyclase toxin

Question 52

Pertussis toxin

Answer 52

A-B exotoxin that inactivate Giz, causing increased cAMP and respiratory secretions. inhibits phagocytic killing and monocyte migration causes lymphocytosis

Question 53

Dermonecrotic toxin

Answer 53

pertussis: vasoconstriction causes ischemic necrosis

Question 54

Filamentous hemagglutin

Answer 54

pertussis: facilitates attachment, highly immunogenic

Question 55

Tracheal cytotoxin

Answer 55

Pertussis: kills cilated epithelia cells stimulates IL-1 release

Question 56

cause of lymphocytosis in pertussis

Answer 56

pertussis toxin

Question 57

pertussis effects

Answer 57

compromises small airways

Question 58

pertussis predisposes patients to

Answer 58

cough atelectasis cyanosis pneumonia

Question 59

catarrhal stage of pertussis

Answer 59

inflammation of mucous membranes, nonspecific URI, 1-2 weeks

Question 60

when are patients with pertussis highly contagious

Answer 60

catarrhal stage

Question 61

paroxysmal stage of pertussis

Answer 61

attacks/spasms, up to 50/day coughing followed by vomiting, "whoop" lasts for weeks

Question 62

during the paroxysmal stage of pertussis

Answer 62

GI complications can occur due to vomiting and increased pressure

Question 63

serious complications of pertussis

Answer 63

**pneumonia** encephalopathy seizures death

Question 64

pertussis occurs in

Answer 64

humans only

Question 65

how to presumptively diagnose pertussis

Answer 65

Serology: ELISA detects Igs to pertussis toxins or adhesions | 4x increase

Question 66

how to definitively diagnose pertussis

Answer 66

culture sample on enriched medium | PCR

Question 67

enriched mediums for pertussis

Answer 67

Bordet Gengou agar | Regan Lowe agar

Question 68

pertussis labs

Answer 68

lymphocytosis

Question 69

Adenylate cyclase toxin

Answer 69

pertussis: similar to pertussis toxin, decreases chemotoxis

Question 70

encapsulated

Answer 70

``` staph aureus pseudomonas strep pneumo (virulent strains) ```

Question 71

optochin sensitive

Answer 71

strep pneumo

Question 72

coagulase positive

Answer 72

s aureus

Question 73

oxidase

Answer 73

morexella

Question 74

lancet shaped

Answer 74

strep pneumo