L7- RTI I Flashcards
adenovirus is a (small/large) (non-/enveloped) (+/-) sense (ss/ds)(RNA/DNA) virus
small/medium non-enveloped (+/-) sense dsDNA (linear) virus
rhinovirus is a (small/large) (non-/enveloped) (+/-) sense (ss/ds)(RNA/DNA) virus
(picornavirus family- icosahedral)
small non-enveloped (+) sense ssRNA virus
coronavirus is a (small/large) (non-/enveloped) (+/-) sense (ss/ds)(RNA/DNA) virus
large enveloped (+) sense ssRNA virus
briefly define the two groups that cause respiratory infections
1) professional invaders: infects healthy tract, more aggressive/virulent
2) secondary invaders: infects those with impaired defenses, less virulent
rhinovirus is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- professional
2- adhesion to mucosa
bordetella pertussis is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- professional
2- interferes with cilia
legionella pneumophilia is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- professional
2- resists destruction w/in alveolar macrophages
corynebacterium diphtheriae is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- professional
2- local tissue damage via toxin production
S. pneumoniae is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- secondary
2-
a) post viral infection (influenza virus) => pneumonia (note S. aureus can infect this way too)
b) depressed resistance seen in elderly, alcoholism, renal/hepatic disease
pseudomonas aeruginosa is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- secondary
2- impaired local defenses (i.e. CF)
haemophilus influenzae is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- secondary
2- current chronic bronchitis, local FB, or tumor
pneumocystis jirovecii is a (professional/secondary) respiratory tract invader with (2) as the key infectious mechanism
1- secondary
2- depressed immune responses as seen in AIDS, neoplastic disease
list the common mechanisms that weaken/defeat the defenses of the respiratory system (hint- 6)
- Smoking: impairs ciliary function, inc mucus
- Pollution: induces inflammation
- Endotracheal Intubation: mucosal injury, impairs ciliary function, site of attachment
- Cough Reflex Suppression: aspiration (seen in impaired consciousness)
- Predisposing Infections: receptor upregulation, setting for secondary invader
- Homeostasis disruption: age, malnutrition, immunosuppression, underlying disease
(cough/sneezing) is more effective at spreading infections
**Sneezing: 100 mph, 100000 droplets
cough: 50 mph, 3000 droplets
list the ways exogenous infections are acquired
1) secretions: nasal/oral, small droplets (hrs), dried droplet nuclei (days)
2) inhalation (i.e. dust, fungal spores)
3) self inoculation: rubbing hands with droplets on eyes, nose, mouth
list the ways endogenous infections are spread or initiate
(usually members of normal microbiota)
1) situations predisposing RT infections
2) normal flora in unusual location: i) relocation due to age, preceding infection, smoker // ii) underlying disease like COPD, asthma, CF
3) preceding infection –> damage –> secondary infection
4) URT flora aspirated into lungs (aspiration pneumonia via mixed flora)
define the following: 1- rhinitis 2- rhinosinusitis / sinusitis 3- nasopharyngitis / rhinopharyngitis 4- pharyngitis
1- nasal mucosa inflammation
2- inflammation of nares, paranasal sinuses (frontal, ethmoid, maxillary, sphenoid)
3- inflammation of nares, pharynx, hypopharynx, uvula, tonsils (common cold)
4- inflammation of pharynx, hypopharynx, uvula, tonsils
define the following: 1- epiglottitis / supraglottitis 2- laryngitis 3- laryngotracheitis 4- tracheitis
1- inflammation of superior larynx and supraglottic area
2- inflammation of larynx
3- inflammation of larynx, trachea, subglottic area
4- inflammation of trachea and subglottic area
Give the term for the following definitions:
(1) inflammation of larynx, trachea, subglottic area
(2) inflammation of trachea and subglottic area
(3) inflammation of nares, pharynx, hypopharynx, uvula, tonsils
(4) inflammation of pharynx, hypopharynx, uvula, tonsils
(5) nasal mucosa inflammation
(6) inflammation of nares, paranasal sinuses (frontal, ethmoid, maxillary, sphenoid)
(7) inflammation of superior larynx and supraglottic area
(8) inflammation of larynx
1- laryngotracheitis 2- tracheitis 3- nasopharyngitis / rhinopharyngitis (common cold) 4- pharyngitis 5- rhinitis 6- sinusitis / rhinosinusitis 7- epiglottitis 8- laryngitis
list and define the 3 common terms used to define infections of LRT
acute bronchitis: inflammation of air tubes / bronchi
bronchiolitis: bronchiolar inflammation
pneumonia: inflammation of one or both lungs
list the 3 ways pneumonias are categorized
Area of Lung Affected: lobar, bronchopneumonia, interstitial
Location of Acquisition: CA, HA, ventilator associated
Causative Agent: bacterial, viral, other
Common Cold:
- (1) alternate names
- (2) most common season
- (3) routes of transmission
- (4) most contagious period
- (5) prognosis
1- rhinitis, nasopharyngitis, rhinopharyngitis
2- fall, winter (although in all seasons)
3- secretions/droplets from another OR self-inoculation post fomite contact
4- first 2-3 days, usually not contagious after first week
5- mild, self limiting disease (great although #1 cause of missing work/school)
The most common cause of the common cold is (1). (2) and (3) are the other very popular causative agents.
1- rhinovirus
2- coronavirus
3- adenovirus
Note- many other viruses may cause rhinitis, but no significant bacterial causes
indicate the most common season of transmission for the following:
(1) rhinovirus
(2) coronavirus
(3) adenovirus
1- summer (+ spring and early fall)
2- winter
3- throughout the year
Note- in order of most common causes for the common cold
In the common cold:
- Sxs start (1) after acquiring virus
- (2) most common Sxs
- (3) if present is usually mild, but is more present in children
- (4) additional Sxs
1- 2-3 days (rarely up to 1 wk)
2- nasal congestion, rhinorrhea, scratchy throat, sneezing
3- fever (low-grade, usually present in young children)
4- watery eyes, cough, sore throat, HA, muscle aches, postnasal drip, dec appetite
list the 4 complications that can stem from the common cold
- acute rhinosinusitis/sinusitis (viral > bacterial)
- LRT disease (unusual): via RSV, HPIV –> acute bronchitis, bronchiolitis, pneumonia
- Asthma / COPD exacerbation (viral)
- Acute Otitis Media (viral, bacterial)
Rhinovirus:
(1) viral family
(2) key features
(3) labile in what condition
(4) subtypes
1- picornaviridae
2- small, non-enveloped, ssRNA(+), icosahedral
3- acidic pH
4- RhV(A, B, C) + by capsid proteins VP(1, 2, 3, 4)
Rhinoviruses are responsible for (1)% of all common colds, mostly in the (2) season. Risk factors include (3). The main complication from the common cold via rhinovirus is (4).
1- 50%
2- summer (+ spring and fall)
3- smoking, crowding (daycare), extreme age (elderly, babies)
4- acute Asthma and COPD exacerbation
Rhinovirus Pathogenesis:
(1) most common route of entry / major group, indicate subtypes
(2) second most common route of entry / minor group, indicate subtypes
(3) least common route of entry, indicate subtypes
(1), (2), (3) all lead to (4) and then (5)
1- ICAM-1 (intracellular adhesion molecule); 90% RhA, RhB
2- LDLR (low density lipoprotein receptor); 10% RhA, RhB
3- HRVC; RhC (unknown pathogensis)
4- inflammation (via CKs)
5- airway remodeling (via GFs)
rhinovirus can survive alone in the environment for….
2 hrs - 7 days
Rhinovirus, indicate the feature for the following functions:
- (1) upper RT infection
- (2) high number of serotypes
- (3) enables transmission
- (4) resistance (or dec sensitivity) to surface cleaners
1- optimal growth at 33-35C
2- antigenic drift
3- stability in environment (relatively)
4- non-enveloped
Rhinovirus, indicate the function of the following features:
- (1) stability in environment (relatively)
- (2) non-enveloped
- (3) optimal growth at 33-35C
- (4) antigenic drift
1- enables transmission
2- resistance / less sensitive to surface cleaners (alcohols, disinfectants)
3- ideal for upper RT infection
4- high number of viral serotypes
