what are the three components of the infectious disease triad?
host
pathogen
environment
diagnosis of pneumonia requires what?
a chest radiograph showing parenchymal infiltrates
acute pneumonia typical findings
- community acquired (CAP)
- measured in hours to days
- onset with chills, fever, and wet cough
- pleura often involved giving chest pain with inspiration (pleuritis)
- micro-aspiration of upper respiratory tract colonizing bacteria
what is the most often found bacteria to causes acute pneumonia?
Strep. pneumoniae
what is the progression of pneumonia in regards to the lungs?
sub-segmental->segmental->lobar consolidation
why has H. influenzae largely disappeared as a cause of pneumonia?
the vaccine
what gram negative bacteria can causes pneumonia?
Klebsiella pneumoniae
what causes walking pneumonia?
mycoplasma pneumoniae
what is lung hepatization?
seen in lobar pneumonia and is when there is a major infiltration of alveoli by PMNs
bacteria that can causes walking pneumonia
mycoplasma pneumoniae
Chlamydophila pneumoniae
what three bacteria can causes environmentally acquired pneumonia?
Legionella pneumophilla (legionnaire's) Coxiella burnetii (Q fever) Chlamydophila psittaci
pulmonary actinomycosis
aspiration pneumonia
Actinomyces spp. anaerobic/microaerophic Gm + bacillus
- oral flora in carious teeth and gingivitis
- aspiration often with unconsciousness
- organism can penetrate any tissue
- *requires long-term treatment (6-12 months)
- Penicillin IV then PO or clindamycin
- sulfur granules
viral pneumonia
respiratory viruses ----common in children; rare in adults Hantavirus (Sin Nombre V.) Coronavirus (SARS, MERS) Bacteria pneumonia with or in the wake of influenza
complications of acute bacterial pneumonia
necrotizing pneumonitis
lung abscess
empyema
what is necrotizing pneumonitis
death of lung parenchyma
what is a lung abscess
excavation of lung parenchyma
what is empyema
spread of infection into potential space between parietal and visceral pleura-
- requires drainage as part of management
- diagnostic via thoracentesis
management of acute pneumonia
Empiric treatment
- microbiological diagnosis is not possible, new tests for antigens and nucleic acids may offer etiological diagnosis
- possible pathogens of acute pneumonia are well established
- Broad spectrum antibiotics to cover most possible pathogens, allowing empiric therapy
- *exception due to resistance of pneumococcus, the leading pathogen for lobar and bronchopneumonia
chronic pneumonia
weeks to months
differential diagnosis
NO empiric treatment
**Requires diagnosis by bronchoscopy or lung biopsy
what would be a classic case of chronic pneumonia?
pulmonary TB
Oral anaerobic bacteria
gram + cocci
peptostreptococcus
Oral anaerobic bacteria
gram+ bacilli
actinomyces
eubacterium
leptotrichia
Oral anaerobic bacteria
gram-cocci
veillonella
Oral anaerobic bacteria
gram - bacilli
fusobacterium
prevotella
porphyromonas
aspiration pneumonia characteristics
stupor, coma, seizures
oropharyngeal flora
community acquired: gram + and anaerobes
hospital-aquired: gram - and S. aureus
is Step pneumoniae alpha, beta, or gamma hemolytic?
alpha
