Pneumonia Flashcards Preview

Respiratory 2 > Pneumonia > Flashcards

Flashcards in Pneumonia Deck (28):

Pneumonia definition and most important clinical point

Infection of the lung parenchyma

**When you are dealing with a patient with pneumonia, the most important thing you can do is figure out what the bug is***


Defense mechs

Nasal clearance

Tracheobronchial clearance...mucociliary escalator

Alveolar clearance...alveolar macrophages phagocytize

Despite the large number of organims in the URT, the LRT is pretty sterile

Think smokers, intubated, long term steroids,


Transmission of pathogens to the lung (asp)

Most commonly - aspiration of organisms that colonize the oropharynx

Some during certain times of the year, some only during certain situations


Inhalation and other ways

Organsism are 1-10 microns...TB, influenza, histoplasmosis

Hematogenous spread

Direct penetration

Direct extension from close infection (overhwelming sepsis)


Patho of lobar

Consolidation of entire lobe of the lung

Pneumococcus causes 90-05%

Red hepatization
Gray hepatization


Broncho vs. lobar

Lobar - entire lobe
Broncho - alvolar spaces around the major bronchi


CXR lobar pneumonia

Lobe will appear white bc full of pus instead of air


Patho of lobar (on slide)

Will see pus in the alveolar space...means when someone coughs, something comes out


Bronchopneumonia patho

Patchy consolidation through more than 1 lobe


Very common at autopsy

Grossly scattered 3-4 cm ofci

PMNs in alveolar space around larger bronchi


Patho of interstitial pneumonitis

Inflammation in the interstitium but NOT alveolar space

Caused by mycoplasma pneumonia and viruses

No gross evidence of consolidation...looks kind of dirty

Micro-lymphocytes in the interstitium


Microscopic - interstitial pneumonia

Widening of all the walls of inflammation


Comps from pneumonia

Lung abscess
Empyema - pus out in the pleural space
Organization - Pt doesn't cough inflammation out and it turns to scar
Bacteremia going to heart valves, CNS, or joints


Typical vs. atypical pneumonia

Typical - pneumococcus

Atypcial - mycoplasma

Atypical looks more normal than typical


Etiology, patho, gross, micro

Strep pnuemoniae is biggest one

Aspiration, attachment of antiphagocytic capsule of pneumolysis

Classic stages of lobar pneunmonia

PMNs since bacterial

Looks clinically typical


Haemophilus infleunzae

Etiology, patho, gross, micro, clinical

Haemophilus type B but also other non-type B due to HiB

Colonization, aspiration, laryngotracheobronchitis can result

Bronchopneumonia or lobar

PMNs bc bacterial

Pediatric emergency


Legionnares dz

Etiology, patho, gross, micro, clinical

Legionella pneumophilia

Colonizes air conditioners...can block ofrmaiton of phagolysosome...can rupture macrophages via pore formign toxins

Bacterial so consolidation

PMNs and macropahges

Depends on health of host..if healthy, feels like flu...dx via urinary antigen testing


Anaerobic pneumonia

Etio, path, gross, micro, clinical

Bacteroides, fusobacteria, actinomyces, microaerophilic cocci

Aspiration and bad teeth

ronchopneumonia or rearely lobar can form abscesses in the lung

Bacterial so heavy PMN infiltrate

Bad teeth, high fever, productive cough



Etio, path, gross and and micro, clinical


More likely to be in skin or soft tissue infections than HA-MRSA

Similar to other bacteria

Younger healtheir with a bilateral necortizing pneumonia and abscesses...these organisms must be covered for in this setting



etiology, path, gorss, macro, clinical

Mycoplasma pneumoniae

Can interfere with cilia and cause desquamation of surface epithelium...passed by resp droplets

Very little seen grossly

Classic interstitial pneumonits

Class dry cough and CXR...PCR is gold std for diagnosis


Chlyamydial pneumonia

Etio, patho, gross, micro, clinical

Obligate intracellular parasite...LPS stimulate inflammation

Can depend on severity

Interstitial lymphs and histiocytes

Usually in young adults 1-3 weeks after a pharyngitis...PCR is gold std


Viral pneumonia

Etiology, patho, gorss, micro, clinical

Influenza, adenovirus, RSV

Spread via droplets, can vary in severity...influenza may get bacterial superinfecion

Congestion but no consolidation

Intersittial lymphs and histiocytes

Sx often not resp...dx done via nasal swab or PCR


Pseudomonas pneumonia

Etiology, path, gorss, micro, cliicial

Pseudomonas aeruginosa

over 50% of hospitals


Bacterial so PMNs in alveolar space

Fever, dyspnea, and CXR during hospitalization..sputum for dx


Enteric gram neg bacilli pneumonia

Etio, path, gross, micro, clinical

Serratia, enterbacter

Colonization and aspiration...klebsiella has antiphagocytic casule

Gross - broncho or rarely lobar...kelbsiella can produce abscess

Bacterial so PMN rich in alveolar space

Fever, sputum, and CXR...blood cultures important...rales may be influenced by hydration of pt


Staph - hospital

Etiology, patho, gross, micro, clinical


Colonization-aspiration or hematogenous from IV site

Broncho, lobar, or abscess

Can be multifocal if hematogenous

Can be dramatic or subtle depending on route


Cell counts of pnuemonia for HIV

And other things

Typical bacteirial can still ocur and be severe

Some infiltrates on CXR are not infection but Kapsoi sarcoma

>200 - bacteiral

50-200 - CMV

Under 50 - pneumocystis


Pneumocystis penumonia

Etio, patho, gross, micro, clinical

Pneuocystis carinii

Ubiquitious organisms tht fills alvolear spaces with little rxn

Lung is solid and airless

ALveoli look foamy

Resistent infiltrate...may be confirmed by BAL and silver stain PCR can be done




SImilar to mono in normal but IC are overhwelemd

Patchy or diffuse infiltrate seen

Classic intranucelar inculsions

IN HIV, common with PCP dx oftne iwth PCR on BAL or evidence of CMV cytopathic effect on cytology


Histoplasmosis pneumonia

Etio, patho, gross, micro, clinical

Histoplasma cpasulatum

Lives in soil and is inhaled...granulomas in normal pt but not in IC

Can be focal airless consolidation

Grandulomas not seen, only yeast

Can look like miliary TB with fever, night sweats and wieght loss...dx by urine antigen testing or culture...PCR is insensitive