Respiratory pathophysiology Flashcards
IL-1β major cellular functions
- Increases E-selectin
- Increases vascular permeability and dilation
* Increases tissue factor release from macrophages and endothelial cells - Increases mucus production in goblet cells
Results in fever
Which increases vascular permeability more, IL-1β or TNF-α?
TNF-α
Which IL increases acute response proteins in the liver?
IL-6
Human adenovirus
What virus is implicated in a viral infection causing both bronchitis and conjuctivitis concurrently in the same Pt?
Adenovirus
Human Rhinovirus
Influenza viral attachement protein (VAP)
Hemmagluttinin (HA protein)
Binds sialic acid
Target for neutralizing Abs
Target of baloxavir
Cap-dependent endonuclease of influenza virus
What influenza type is only found in humans?
Influenza B
Where is influenza’s viral RNA replicated in the infected host cell?
Host cell nucleus - influenza = (-)ssRNA genome
How does influenza promote PNA and secondary bacterial infections?
Infecting respiratory epithelium and disabling the mucociliary escalator - also cleaving sialic acid and thinning mucus - causes mucus to fall back into lower respiratory tract
Which influenza type causes epidemic outbreaks only (not pandemic)?
Influenza B
Ag drift only
How does influenza A cause pandemics?
Antigenic shift of HA or NA gene(s)
Most virulent type of Haemophilus influenzae
Serotype B - polysaccharide capsule made from polyribitol-ribosyl-phosphate
What type of H. influenzae is responsible for sinusitis and otitis media?
Non-typable - unencapsulated
What factors does H. influenzae require to grow on agar?
X and V factors
Boiled BAP - chocolate agar
X factor = hemin
V factor = NAD+
Tx of H. influenzae PNA
-Ceftriaxone/cefotaxime
Moraxella catarrhalis
General features
Grame (-) diplococci
Strictly aerobic
Oxidase and catalase (+)
Normal flora (28-100% of humans within first year of life)
Differentiated from Neisseria by its ready growth on BAP culture
Also “Hockey Puck sign”
Tx for PNA caused by Moraxella catarrhalis
Augmentin
Bordatella pertussis
General features
Gram (-) coccobacilli in singles and paire
Aerobic
Fastidious growth requirements
Oxidase (+)
Pertussis toxin
AB subunit toxin
ADP-ribosylates GTP-binding (G) proteins that alter inhibitory regulation adenylate cyclase activity
Wide range of effects on immune cells (typically supresses immune response and migration)
Clinical progression of whooping cough
- Prodromal stage (common cold sxs)
- Paroxysmal: cough first appears (2-3 weeks)
- Convalescent: bacteria gone, cough remains for several weeks
Growth requirements of B. pertussis in laboratory
Bordet-Gengou aka charcoal horse blood agar
Provides nicotinamide
Can also be detected by PCR
Tx for whooping cough
Macrolide (azithromycin)