S. aureus virulence factors in Otitis Externa (3)
encapsulated
coagulase +
B-hemolytic
psuedomonas virulence factors in Otitis Externa (3)
encapsulated
Pyocyanin: blue, generates ROS
Pyoverdin: fluorescent green, sequesters iron
S. pneumo characteristics (3)
AOM & Sinusitis
encapsulated
a-hemolytic
optochin sensitive
M. catarrhalis characteristics (2)
oxidase positive
B-lactamase
diptheria physical signs (2)
formation of psuedomembrane
bull neck
Corynebacterium characteristics (3)
palisades/Chinese letters/V formation shape
metachromatic (volutin) granules
grows on blood agar
what stimulates the diptheria toxin?
low [iron]
diptheria toxin process (5 steps)
binds to heparin binding EGF receptor –> endocytosis –> vesicle acidifies –> A subunit moves into cytosol –> A subunit inactivates EF-2
diptheria toxin inactivates?
EF-2
agar for Corynebacterium isolation
Loeffler’s: enhances formation of volutin granules
Cysteine-tellurite agar: distinctive black to tellurite reduction
methods of testing for diptheria toxin production (4)
Elek test
PCR
ELISA
Immunochromatographic strip assay
function of adhesins in pertussis
mediate attachment to integrins & colonization of ciliated respiratory epithelium
4 exotoxins of pertussis
pertussis toxin
adenylate cyclase toxin
dermonecrotic toxin
tracheal cytotoxin
pertussis toxin MOA
lympocytosis
adenylate cycle MOA
decreased chemotaxis
dermonecrotic toxin MOA
vasoconstriction –> ischemic necrosis
tracheal cytotoxin MOA (2)
kills ciliated respiratory epithelial cells
stimulates IL-1 release
3 stages of pertussis
catarrhal stage
paroxysmal stage
convalescent stage
diagnosis of pertussis (4)
ELISA
Bordet-Gengou agar
Regan-Lowe agar
PCR
PIV 3 characteristics on virus?
Hemagglutinin
Neuramindase
Novel Fusion (F) protein- causes synctica formation
PIV diagnosis (2)
direct viral isolation from throat swabs
direct FAB test identifies agent of croup
cause of symptoms in RSV?
inflammatory response
diagnosis of RSV? (2)
rapid antigen tests
immunofluorescence assay
most common etiology of lower resp. infection in kids <4 y/o?
RSV
SARs characteristics (3)
novel Coronavirus
emerged in China
resp. & fecal-oral spread
MERs characteristic
novel Coronavirus
where does acute respiratory disease mostly effect?
upper resp. tract mucosa- cells lining nasal passage & pharynx
type of viruses that cause acute resp. disease
adenoviruses & unknown viruses (majority)
rhinoviruses
coronaviruses (least)
major vector of rhinoviruses?
hands
cure for the common cold (2)
hand-washing stops transmission
Picovir
H hemagglutinin fxn in flu
viral attachment
N neuramindase fxn in flu
viral penetration & release
flu complications (3)
secondary bacterial pneumonia
Reyes Syndrome
Guillain-Barre Syndrome
causes of secondary bacterial pneumonia after flu (3)
S pneumo
S aureus
Hib
neuraminadase inhibitors (2)
Oseltamivir & Zanamivir
Amantadine & Rimantadine do what
stops viral uncoating
oseltamivir & zanamivir do what?
stop spreading/release of virus
point mutations of H or N proteins
Antigenic drift
Recombination involving entire genome segments encoding the H or N gene
Antigenic shift
2 forms of chlamydiae in life cycle
elementary body
reticulate body
chlamydia elementary body
infectious, nongrowing form
chlamydia reticulate body
growing form
which chlamydia causes infant pneumonia
C. trachomitis