9 Diseases of the Respiratory System Flashcards
name 3 features of innate defenses of the respiratory system
- mucociliary escalator (traps debris & moves out)
- alveolar macrophages (dust cells) most important
- mm of chest wall & diaphragm (coughing & clearing)
name 4 examples of bacterial infections of the respiratory system
- otitis media
- pharyngitis (strep throat)
- scarlet fever
- diphtheria
otitis media can be ____ or ____
viral or bacterial
when is otitis media most common?
between ages 3mo to 3yrs
name 3 etiologic agents of otitis media
- streptococcus pneumoniae
- staphylococcus aureus
- haemophilus influenzae
otitis media may be spread locally, resulting in…
- acute petrositis (infection of temporal bone)
- labrynthitis
intracranial spread of otitis media may cause…
- meningitis (most common)
- brain abscess
- subdural empyema
- epidural abscess
- lateral sinus thrombosis
- otitic hydrocephalus
symptoms of mastoiditis
- abscess forms in the bone, skin covering can become swollen, red, tender
- fever
- pain around & within ear (persistent & throbbing)
- creamy, profuse discharge from ear
- hearing loss can become progressively worse
signs & symptoms of sinusitis
- pain & tenderness
- congestion & obstruction of nose
- reduced ability to smell (hyposmia)
- bad breath (halitosis)
- productive cough (especially at night)
- swelling over affected sinus
what causes sinusitis?
usually a bacterial super-infection after sinus drainage has been compromised
pharyngitis is classically known as the infection ____
strep throat
etiologic agent of pharygitis
streptococcus pyogenes
signs & symptoms of pharyngitis
- can cause abscesses on tonsils
- can cause complications of scarlet fever, toxic shock syndrome, rheumatic fever
scarlet fever is caused by…
group A streptococci: streptococcus pyogenes
in what population is scarlet fever commonly seen?
children under 18yrs
pathogenesis of scarlet fever
- symptoms begin w/ rash: tiny bumps on chest & abdomen, more red in armpits & groin, lasts 2-5 days
- very sore throat w/ white or yellow papules
- fever of 38.3*C (100.9 F)
- lymphadenopathy
- headache, body aches, nausea
- tongue coated w/ bacteria
etiologic agent of diphtheria
corynebacterium diphtheraie
diphtheria is a more localized type of the infection ____
severe pharyngitis
diphtheria may be accompanied by…
pseudomembrane in throat composed of fibrin, leukocytes, cell debris, dead bacteria
how is diphtheria transmitted?
- droplet aerosol
- direct contact w/ colonized skin
- fomites
diphtheria produces the toxin ____
myocarditis (targets the heart)
diphtheria may involve…
- multiple organ systems
- skin
describe diphtheria of the skin
simple pustules to non-healing ulcerations
name 2 examples of viral infections of the upper respiratory system
- rhinovirus (common head cold)
- parainfluenza (types 1 & 3)
describe the serotypes of rhinovirus
- several hundred exist, <50% have been characterized
- 50% are picoronaviruses (smallest & simplest)
- single-stranded RNA
- major cause of mild upper respiratory tract infections
describe the pathogenesis of rhinoviruses
- infection seen throughout the year (epidemic in spring & early fall)
- incubation period: 2-3 days
- acute symptoms: 3-7 days
- mild infection w/ little damage to body
how many types of parainfluenza virus (HPIV) exist, and which are the most important?
- 4 types
- types 1 & 3
parainfluenza viruses belong to what group?
paramyxovirus group
- single stranded RNA virus
- contains hemagluttinin & neuraminidase
parainfluenza virus is a serious problem in what population?
infants & small children
compare parainfluenza vs influenza
- parainfluenza virus replicates in cytoplasm; influenza replicates in nucleus
- parainfluenza virus is more stable than influenza (very little mutation, little antigenic shift, no antigenic drift)
pathogenesis of parainfluenza infection of upper respiratory tract
- fever
- runny nose (rhinorrhea)
- cough
- sore throat
- sneezing
- wheezing
- ear pain
- decreased appetite
pathogenesis of parainfluenza infection of lower respiratory tract
- croup (infection of larynx, trachea, bronchi)
- bronchitis
- bronchiolitis
- pneumonia
HPIV1 is also known as ____
sendai virus
compare the effects of HPIV1 and HPIV3
HPIV1:
- major cause of croup in infants & young children
- causes severe pharyngitis & tracheobronchitis
HPIV3:
- major cause of severe lower respiratory infection in infants & young children
- causes bronchitis & pneumonia in children <1yr
compare HPIV1 & 3 in terms of when they occur
HPIV1: outbreaks usually in fall
HPIV3:
- 50% of all children exposed within 1st yr of life
- infections occur throughout the year
name 8 examples of bacterial infections of the lower respiratory tract
- bacterial pneumonia
- mycoplasmal pneumonia
- TB
- pertussis
- inhalation anthrax
- legionnaire’s disease
- Q fever
- psittacosis
bacterial pneumonia may be caused by…
a variety of organisms
(one of most serious infections)
name 5 high risk groups for community acquired pneumonia
- elderly
- children <2yrs
- african-americans
- native americans
- alaska natives
signs & symptoms of pneumococcal pneumonia
- fever >39*C (102.2 F)
- chest pain
- purulent sputum
what is the etiologic agent of pneumococcal pneumonia?
streptococcus pneumoniae
what is the etiologic agent of mycoplasmal pneumonia?
mycoplasma pneumoniae
describe the etiology of mycoplasmal pneumonia
- mild form of pneumonia
- accounts for 10% of all pneumonias
- “walking pneumonia”
- most common between 5-15yrs
- found in temporal climates
pathogenesis of mycoplasmal pneumonia
- incubation period: 2-15 days
- insidious onset: fever, headache, malaise
- infection affects trachea, bronchi, bronchioles
- may extend to alveoli
- organisms shed in upper respiratory secretions: 2-8 days before symptoms; 14wks post-infection
signs & symptoms of mycoplasmal pneumonia
- mild tracheobronchitis
- sore throat
- otitis media
- persistent, nagging, unproductive cough
describe the etiology of pulmonary tuberculosis
- ~2 billion people infected globally
- HIV/AIDS has significant impact
- poverty & poor living conditons
- drug resistance due to non-compliance
signs & symptoms of tuberculosis
initial symptoms similar to other respiratory tract infections EXCEPT:
- fever (38*C; 100.4 F)
- fatigue
- weight loss
- chest pain
- shortness of breath
- hacking cough
- hemoptysis (coughing blood)
describe the current trends of tuberculosis
- 1/4 of world population carries
- 50,000,000 people are infected w/ multiple drug resistant (MDR) strains of TB
- 80% of US cases are foreign-born
- TB is a re-emerging disease
etiologic agent of tuberculosis
myobacterium tuberculosis
how is myobacterium tuberculosis stained?
acid-fast+ bacillus/weakly gram+ bacillus
pathogenesis of primary TB
- occurs when host encounters pathogen for first time
- organisms move to alveoli
- cell-mediated immune response begins
- if primary lesion not contained -> tubercles/granulomas
what are tubercles?
- aggregates of macrophages containing bacteria, surrounded by fibroblasts & lymphocytes
- center = caseous necrosis
- calcified: ghon complex
pathogenesis of secondary TB
- AKA latent TB
- due to reactivation of old lesions: advanced age; immunocompromization due to co-infection w/ HIV/AIDS
OR - gradual progression of primary TB
diagnosis of TB is dependent upon…
- PDD: purified protein derivative skin tests (mantoux or tine)
- chest film showing tubercles or consolidation
- sputum sample w/ acid-fast staining
- biopsy
treatment of TB
- triple therapy cocktail: Isoniazid (INH), Rifampicin (RFP), Pyrazinamide (PZA)
- all 3 taken 1x/day for 2mo
- INH & RFP taken for 9 more months
- compliance important but difficult bc of side effects of drug therapy (toxicity in liver & kidney)
what is directly observed therapy?
- delivery of scheduled drug doses by a healthcare worker: patient’s ingestion/injection of drugs is directly administered, observed, and documented
- helps prevent spread of TB and occurrence of MDR-TB
describe the etiology of whooping cough
- etiologic agent: bordetella pertussis
- highly contagious
- infects 80-100% of susceptible individuals
- mortality highest in infants & children <1yr
- re-emerging disease
what is the medical term for whooping cough?
pertussis
prevention of pertussis
DTaP vaccine
pathogenesis of perussis
- has affinity for ciliated bronchial epithelium
- after attaching, produces tracheal toxin: immobilize & destroy ciliated cells
- persistent cough from inability to move mucus
- does not invade cells/tissues of respiratory tract
- incubation period: 7-10 days
name the stages of pertussis
- primary: catarrhal
- secondary: paroxysmal
- tertiary: convalescence
describe the primary stage of pertussis
- 1-2wks
secondary stage of pertusis
tertiary stage of pertusis
complications of pertusis
inhalation anthrax
pathogenesis of anthrax
where is Legionnaire’s disease found?
- ubiquitous in fresh water
- lives inside Acanthamoeba
- undetected in healthy people
etiologic agent of Legionnaire’s disease
Legionella pneumophila
transmission of Legionnaire’s disease
- transmitted as humidified aerosol
- facultative intracellular parasite
Legionella pneumophila infect ____, which show ____ morphology
alveolar macrophages
coiled
symptoms of Legionella pneumophila
where is Q fever found?
- grows well in placenta of animals
- contaminated soil
transmission of Q fever
what type of infection is Q fever?
etiologic agent of Q fever
coxiella burnetii
pathogenesis of Q fever
Psittacosis is also known as ____
ornithosis
what type of pneumonia is psittacosis?
zoonotic
what are the most common hosts of psittacosis and how is it contracted?
etiologic agent of psittacosis
common name of psittacosis
acute symptoms of psittacosis
occasional systemic complications of psittacosis
75-80% of all acute respiratory tract infections in the US are of ____ origin
viral
incubation period of viral lower respiratory tract infections
short: 1-4 days
how can viral lower respiratory tract infections be transmitted?
- direct: through droplets
- indirect: through transfer of contaminated secretions
influenza is also known as ____
name 3 serotypes of influenza
serotype A
serotype B
serotype C
influenza outbreaks
acute influenzal syndrome
pathogenesis of influenza
when infected by influenza, respiratory epithelium may not be restored for…
2-10 weeks
respiratory syncytial virus outbreaks (RSV)
virus shed of RSV
RSV affects…
incubation period of RSV
clinical signs of RSV
RSV in infants
common name for Hantavirus Pulmonary Syndrome
Hantavirus Pulmonary Syndrome infection is associated with…
transmission of sin nombre
mortality rates of sin nombre
fungal spores are ____ and found in…
ubiquitous
- found in soil
- found in homes
- resident flora
etiologic agent of pneumocystis pneumonia
pneumocystis pneumonia is common in ____
symptoms of pneumocystis pneumonia
pathogenesis of pneumocystis pneumonia
etiologic agent of blastomycosis
blastomyces dermatitidis
who is most commonly affected by blastomycosis?
pathogenesis of blastomycosis
etiologic agent of histoplasmosis
where is histoplasmosis found?
pathogenesis of histoplasmosis
etiologic agent of coccidiodomycosis
what causes valley fever?
pathogenesis of valley fever
etiologic agent of aspergillosis
where is aspergillosis found?
what population is commonly affected by aspergillosis?
pathogenesis of aspergillosis
