Chapter 22: respiratory tract infections, neoplasms, and childhood disorders Flashcards
What are the three components of respiration
1) ventilation
2) perfusion
3) diffusion
What are the two types of shunts?
1) anatomical: blood bypasses lungs
2) physiological: mismatch of ventilation and perfusion resulting in in adequate supply of O2
What is the percentage of water and solutes in snot?
95 percent water
5 percent solutes
- proteins, salts, immune cells
How much snot is produced day?
1-2 L
What are the five most common respiratory infections?
common cold rhinosinusitis influence pneumonia TB
List five viruses, the season they are prevalent in for the common cold
1) RHINOVIRUS: early fall, late spring
2) SYNCYTIAL VIRUS: winter spring
3) CORONAVIRUS: winter spring
4) ADENOVIRUS: winter spring
5) PARAINFLUENZA
What part of the respiratory infection does the common cold affect? What is the one exception?
the upper resp tract
PARAINFLUENZA infects lower then upper
What 2 common cold viruses affect children under 3?
SYNCYTIAL virus
PARAINFLUENZA
What common cold virus affects people ages 5-50
RHINOVIRUS
What are the risk factors for the common cold?
age
previous exposure
season
What are the two ways the common cold can be transmitted?
aerosolization (less dangerous)
fomite transference
- contaminated obj
How is incubation of the common cold?
5-7 days
When is the common cold transmittable?
0-3 days after symptom onset
What are the portals of entry for the common cold?
nasal mucosa
conjunctiva (most common)
Describe the manifestations of the common cold
sore/scratchy throat
Nasal congestion or runny rhinorrhea
sneezing/coughing
malaise, fatigue, h/a, myalgia
fever in children, less common in adults
What type of treatment approach is used for the common cold?
symptomatic
What are the six risk factors for rhinosinusitis/sinusitis?
ALL OBSTRUCT DRAINAGE
1) upper resp tract infections
2) allergic rhinitis
3) nasal polyps
4) pressure changes
5) decongestant misuse
6) swimming and diving
What are the three types of rhinosinusitis/sinusitis?
ACUTE:
viral
bacterial (less common, inc duration)
fungal (rare)
SUBACUTE (4-12 wks)
CHRONIC (>12 wks)
What are the three common organisms (2 viruses, one bacteria) that cause acute rhinosinusitis/sinusitis?
rhinovirus
haemophilus influenza
streptococcus pneumonia
What is the common cause of chronic rhinosinusitis/sinusitis?
fstaphylococcus aureus
allergens
Describe the manifestations of rhinosinusitis/sinusitis
similar to cold/allergic rhinitis
1) maxilla pain/pressure inc on bending
2) h/a, PURULENT nasal discharge, FEVER, dec smell
3) PAIN IN TEETH
list the 4 ways that rhinosinusitis/sinusitis is treated
1) abx if necessary
2) intranasal corticosteroids
3) topic alpha-adrenergic decongestants
4) surgery for chronic
After AIDS, what is the last uncontrolled pandemic killer of humans?
Influenza
What age group is influenza infection highest in?
Children
What age group is mortality for influenza greatest in?
elderly
What are the two types of influenza that can cause epidemics?
Influenza A and B
What is the more mild form of influenza
influenza C
Explain what the antigen drift is in relation to influenza
RNA segments alter during replication creating new subtypes
make it difficult to vaccinate
How is influenza spread?
inhalation of droplets
Describe the incubation period and contagious period for influenza
INCUBATION: 1-4 days
CONTAGIOUS: 24 hrs prior and days after symptom onset
List the symptoms of influenza in order of pathogenesis.
1) rapid onset of upper resp infection
2) epithelial dmg is possible resulting in rhinorrhea
3) malaise
4) fever, chills
5) myalgia, h/a, cough, sore throat
List six complications of the flu
SINUSITIS OTITIS MEDIA BRONCHITIS BACTERIAL PNEUMONIA VIRAL PNEUMONIA REYE SYNDROME
What is reye syndrome?
rare but often fatal condition of…
encephalitis and liver swelling
What is otitis media?
middle ear inflammation
What groups of the population (4) is the flu shot recommended for?
1) > fifty years old
2) immunosuppressed
3) chronic health issues
4) high risk environment
When is the flu shot contraindicated?
1) <six months old
2) allergic reactions to components
3) acute febrile illness
4) h/o gullaine-barre syndrome
What is the sixth leading cause of death in Canada?
pneumonia
What is pneumonia?
resp disorder involving inflammation of the structures of the lung
What are the 2 general causes of pneumonia?
1) Infectious
2) non-infectious (ex gastric secretions aspirated)
List the five risk factors for pneumonia
1) impaired immune system
2) chronic lung disease
3) airway instrumentation
- tracheostomy
4) mechanical ventilation
5) strong microorganism
What is it called when you get pneumonia r/t mechanical ventilation?
VAP: ventilation assisted pneumonia
What is the criteria to be diagnosed with community acquired pneumonia?
must be acquired outside hospital or within 48 hours of admission
What are the most common causes of community acquired pneumonia? (microorganisms) (4)
STREPTOCOCCUS PNEUMONIA
haemophilus influenza
staphylococcus aureus
gram neg bacilli
What are the most common causes of hospital acquired pneumonia? (nosociomal)
pseudomonas aeruginosa staphylococcus aureus enterbacter species klebsiella pneumonia Escherichia coli seratia species
What part of the respiratory tract does hospital acquired (nosociomal) pneumonia usually affect?
lower respiratory tract
What is the most common organism for community acquired pneumonia? What is this type of pneumonia called?
Streptococcus pneumonia
Pneumococcal pneumonia
where does streptococcus pneumonia colinze?
in the mucous membrane of the nasopharynx
may not progress
What feature of streptococcus pneumoniae increases its durability?
has a polysaccharide capsule that delays digestion by phagocytes
List the manifestations of pneumonia
1) fever
2) malaise
3) chills
4) productive cough
5) dec AE and crackles
6) pleuritic pain
7) elderly may not have fever, but instead loss of appetite and conffusion
What is legionnaire disease?
it Is pneumonia caused by inhalation of aerosolized contaminated water/soil
What are some objects that could cause the spread of legionnaire disease?
air conditioners
large water tanks
What bacteria causes legionnaire disease?
Legionella pneumophila
Describe the manifestations of legionnaire disease
same as pneumonia, but
rapid onset
1) dry cough
2) diarrhea
3) CNS alterations
4) arthralgia
What is the usual cause of primary atypical pneumonia?
mycoplasma pneumoniae
Describe the manifestations of primary atypical pneumonia
Patchy lung involvement
typical pneumonia symptoms but:
1) minimal lung consolidation as confined to alveoli and pulm institium
2) moderate amount of sputum
3) minimal rise in WBC
What is the biggest risk and the implication of this risk of primary atypical pneumonia?
damage to the lung epithelium predisposing lungs to other infections
What organism is the causes the most deaths on its own?
TB
What bacteria causes TB? describe its characteristics
Mycobacteria tuberculosis hominus
1) airborne droplet
2) waxy cell wall (abx resistance)
3) aerobic (O2 rich environment)
List 3 risk factors for TB
1) living in a country with high incidence
2) crowded/confined living conditions
3) immunocompromised
Describe the pathogenesis of TB
1) airborne droplet inhaled and settles in alveoli
2) macrophage engulfs, bacteria multiply inside until macrophage ruptures
3) more WBC and fibroblasts accumulate
4) formation of granuloma
5) lymphocytes activated in a delayed hypersensitivity response to release cytokines that can kill bacilli (can also dmg lung tissue)
Describe what primary TB is.
not previously unsensitised.
often asymptomatic and develop latent TB (non active, non contagious)
5 percent progress to active TB
Describe the manifestations of primary TB
Fever pleuritic pain wt loss fatigue night sweats cough/dyspnea
What is secondary TB?
it is reinfection or reactivation of primary tb lesion
cell mediated hypersensitivity dmgs airway causing cavitation
Describe the manifestations of secondary TB
low grade temp night sweats fatigue anorexia wt loss cough dyspnea orthopnea (SOB
What is a potential complication of secondary TB?
pleural effusion
Describe the treatment for TB
multidrug regimen with chemo
DRUGS: izonazid, rifampin, pyrazinamide, ethambutol
VACCINE: BCG bacillus calmette-buerin
Explain what a positive TB skin test indicates
It is triggered by a cell mediated immune response
it indicates past exposure, not necessarily current infection/active
What are paraneoplastic syndromes?
syndromes caused by secretions from tumor
anorexia, cachexia, and fever are often considered this