Respiratory Tract Infections Flashcards
Upper respiratory infectons
Common cold laryngitis otitis media sinusitis pharyngitis
Lower respiratory
Tracebronchitis
Pneumonia
Host defenses
Nose hairs for a filter Mucocilliary escalator Cough and gag reflux IgA, surfactant, complement Macrophages and neutrophils
Risks for respiratory tract infections
Younger than 5 older than 65 cigarette smokers indoor air pollution winter months asthma, diabetes, AIDS
Cause and symptoms of otitis media
narrowing and obstruction of the Eustachian tubes
fever, headache, ear pain
Most common etiologic agent of otitis media
Streptococcus penumoniae
How do we treat otitis media?
amoxicillin + calvulanate (since bacteria tend to have beta lactamases)
How can you grow haemophilus influenza
V and X factors in blood (found in chocolate agar)
Diagnosis for otitis media
Look at the membrane in the ear
If not responding to therapy, collect gram stain
What type of treatment is normally used for otitis media?
Empiric (we know they have an infection but don’t know the causative agent)
Treatment for recurrent ear infections
Tube in the ear
It’ll eventually fall out and heal spontaneously
What bacteria can cause pharyngitis?
Streptococcus pyogenes
Bacteria traits of strept pygogenes..
gram positive
cocci
How do we treat streptococcus pyogenes? What does it do?
Penicillin
- prevent rheumatic fever
- alleviates symptoms
- decreases spread
Tracheobronchitis
excessive mucus indicing a cough for a period of 3 mo to 2 years
Chronic obstructive pulmonary disease
impaired mucociliary clearance making healthy lungs more susceptible to bacteria that secrete IgA protease
IgA protease
gets rid of secretory IgA so bacteria can attach
Pneumonia
most common infectious cause of death in the US
fever, coughing, chest pain, rapid breathing
Fluid, blood, and cells collect in the alveoli
Klebsiella pneumoniae and pseudomonas aergoginosa
multi-drug resistant
very hard to treat
swaps plasmids with other bacteria so it can acquire efflux pumps and betalactamases
Do we culture the specimen to determine what is causing pneumonia?
No, culturing doesn’t reduce mortality. Use empiric treatment.
How is TB spread?
respiratory droplets
coughing
sneezing
singing
Latent TB infections
90% of people never become symptomatic, others do after immune system weakens
Pathogenesis of TB
bacteria are inhaled, macrophages pick up the bacteria, cells are recruited and the bodies inflammatory response kills lung tissue (chronic tissue necrosis)
Phagosome avoids fusion with the lysosome
How do we test for TB?
Mantoux test
tuberculin skin test
