pneumonia

Question 1

What mediates pain?

Answer 1

prostaglandin E2 and bradykinin

Question 2

What are the CXR patterns for pneumonia? bacteria vs. viral

Answer 2

lobar pneumonia, bronchopneumonia (brochoproblems). and interstitial pneomonia (incr. on lung markings)
lobar and bronchopneumia are usually bacterial, while interstitial pneumonia is usually viral.

Question 3

lobar pneumonia: definition, casues

Answer 3

consolidation of an entire lobe, usually bacterial: S. pneumo (95%), and klebsiella.

Question 4

What should I know about klebsiella in terms of lobar pneumonia?

Answer 4

enteric flora that is aspirated: elder in NHs, alcoholics, diabetics. this bug has a THICK MUCOID CAPSULE, so patients present with currant jelly gelatinous sputum. It is often complicated by abscesses.

Question 5

What are the phases of lobar pneumonia?

Answer 5

congestion, red hepatization (exudate with blood and neutrophils- lung looks solid), grey hepatization (red blood cells break down), resolution

Question 6

What is bronchopneumonia?

Answer 6

scattered patchy consolidation centered around bronchioles. often multifocal and bilateral. it is PATCHY.

Question 7

What are key casues of bronchopneumonia?

Answer 7

S. aureus, H flu, pseudomonas, moraxella, legionella

Question 8

S. aureus and bronchopneumonia?

Answer 8

most common cause of secondary pneumonia (pneumonia superimposed on a viral URI), often complicated by abscess or empyema (pus in the pleural space)

Question 9

H flu and bronchopneumonia

Answer 9

common cause of secondary pneumonia or pneumonia superimposed on COPD

Question 10

What bugs commonly cause pneumonia superimposed on COPD?

Answer 10

H. flu, moraxella, legionella

Question 11

What should I know about legionella?

Answer 11

often associated transmitted by water soucres. intracellular ogranism best visualized with a silver stain. causes community acquired bronchopulmonary pneumonia, esp. in COPD and immunocompromised pts.

Question 12

What is interstitial pneumonia?

Answer 12

diffuse interstitial infiltrates. presents with mild URI symptoms- minimal sputum, cough, low fever. air sacs are pretty empty, but there is inflammation in the interstitial spaces.

Question 13

What is the most common cause of interstitial pneumonia?

Answer 13

mycoplasma pneumonia. can make an autoimmune hemolytic anemia (IgM against antigen on RBCs causes cold hemolytic anemia). no visible on gram stain because no cell wall.

Question 14

What is the most common casue of atypical pneumonia in infants? post transplant?

Answer 14

RSV in babies, CMV post transplant

Question 15

How is influenza virus related to pneumonia?

Answer 15

the virus itself can cause atypical pneumonia. it is also the most common casue of superimposed S. aureus or H flu bacterial pneumonia

Question 16

coxiella burnetii

Answer 16

cause of atypical pneumonia, esp. in famrers and veterinarians (spores are deposited on cattle by ticks or are present in cow placenta). it is classically associated with a HIGH fever (Q fever). it is a rickettsial infection, but is different from most others b/c it causes pneumonia and does not require an arthropod vector, and does not produce a skin rash

Question 17

What causes aspiration pneumonia? Where is the pneumonia most common?

Answer 17

anaerobic bacteria in oropharyns (bacteroides, fusobacteriu, peptococcus). usually in right lower lobe abcess

Question 18

What is seen in primary TB?

Answer 18

focal caseating necrosis in the lower lobe of the lung and hilar lymph nodes. foci undergo fibrosis and calcification to form a Ghon complex (area of fibrosis and calficifation). usually asymptomatic. Ghon complex classically subpleural. Ghon complex can reactivate

Question 19

What is seen with secondary TB?

Answer 19

reactivation, at the apex of lung. forms cavitary foci fo caseous necrosis, or miliary pulm TB with lots of scattered locations, to TB bronchopneumonia

Question 20

Stain for TB?

Answer 20

red organisms on AFB stain

Question 21

Where can TB go?

Answer 21

meninges, usually at the BASE of the brain, cervical lymph nodes, sterile pyuria with spread to the kidneys, lumbar vertebrae (pott disease)

Question 22

What conditions cause lung abscesses? Organisms?

Answer 22

bronchial obstruction (think cancer), or aspiration of oropharyngeal contents (esp. in pts predisposed to aspiration). usually S. aureus or anaerobes (like bacteroides, fusobacterium, peptostreptococcus)

Question 23

What is often seen on CXR for lung abscesses?

Answer 23

air fluid levels