Bacterial respiratory pathogens Flashcards
which pathogen is obligate intracellular
chlamydia psittaci
elementary body
metabolically inactive form of chlamydia psittaci
infectious phase
reticulate body
intracellular, non infectious form of chlamydia psittaci
chlamydia causes
parrot fever
speed of chlamydia growth
slow
major symptoms of parrot fever
flu like symptoms + respiratory infection
parrot fever diagnosis
exposure to birds
clinical presentation
positive antibody titer for chlamydia
treatment of parrot fever
tetracycline
treat 10-14 days post fever to prevent relapse
description of Haemophilus influenzae
gram negative coccobacillus grows on chocolate agar- need Hematin and NAD to grow CO2 rich environment encapsulated no toxins
speed of H influenza growth
fast
risk factors for H influenzae
sickle cell asplenia HIV antibody/complement deficient chemo/radiation stem cell transplant
description of pertussis
gram negative coccobacillus slow growing fastidious strict aerobe releases toxins
pertussis causes
whooping cough
treatment of pertussis
antibiotics in stage 1
once cough starts antibiotics do not work (bug gone)
catarrhal stage of pertussis
stage 1- sticks to trachea via fimbriae
URI
paroxysmal stage of pertussis
severe whooping cough
toxin release
vomitting, weight loss, dehydration
possible neurological damage
location of pertussis bugs
trachea- destroy epithelium
major signs of pertussis
cough
leukocytosis–increased WBC because macrophages in bone marrow attacked by toxins so they can’t break them down
toxins released by pertussis and their functions
pertussis toxin
adenylate cyclase toxin
pertussis toxin
long range immunosuppressor
inhibits neutrophil and macrophage recruitment
blocks Gi –> increase cAMP
adenylate cyclase toxin
short range immune cell suppressor
kills macrophages
local neutrophil deregulation
turns ATP into cAMP
pertussis incubation period
7-10 days
why is the acellular pertussis vaccine bad
Th2 response instead of Th1/Th17 response
does not stop transmission of bacterium
