export_upper respiratory pathogens i Flashcards
Components of the URT
Conjunctiva
Nasolacrimal ducts
Middle ear
Nose
Pharynx
Sinuses/nasal cavity
Larynx
Epiglottis
Where does bacteria end up in the URT
Trachea or terminal airway
Where do viruses end up in the URT
Terminal airway and alveoli
Potentially suspended in air
Sterile URT tissues
Mastoid air cells
Middle ear
Sinuses
Trachea
Bronchi and bronchioles
Alveoli
Describe the sterility of the conjunctiva
It’s supposed to be sterile, but because of its location it is exposed to many organisms
Colonization is really uncommon, so it’s still considered sterile
Normal flora of the nose
Staphylococcus epidermis
Staphylococcus aureus
Corynebacterium spp.
Clinical relevance of Staph. aureus
About 20% of people have this in the normal population
People in hospitals have a higher percentage
Staph. epidermis features
Gram positive cocci clusters
Facultative anaerobes
Staph. aureus features
Gram positive cocci clusters
Facultative anaerobes
Corynebacterium spp. features
Gram positive rod
Pleomorphic
Non-spore forming
Nasopharynx normal flora
Streptococcus
Moraxella catarrhalis
Bacteroides
Bacteria in the Strep. viridans group
S. mutans
S. mitis
S. milleri
S. salivarius
Strep. viridans features
Gram positive cocci chains
Moraxella catarrhalis features
Gram negative diploid-coccobacillus
Aerobic
Bacteroides features
Strict anaerobe
Only if someone’s anatomy allows for oxygen-free pockets
URT pathogens with seasonal association
Strep. pneumoniae
Haemophilus influenzae
Neisseria meningitides
Moraxella catarrhalis