S8C69 - empyema and lung abscess

Question 1

Empyema

Answer 1

• common causes: PNA, aspn PNA, extension of a lung abscess, hemothorax that become infected, complication of trauma
• suspect of symptoms of PNA are not resolving, may have wt loss, anemia, night sweats

Question 2

Empyema: Dx

Answer 2

-aspn of purulent material on thoracentesis
Plus one of:
-positive gm stain or culture from aspirate
-plural fluid glucose 1000 UI/L

Question 3

3 stages of empyema

Answer 3

1. exudative - pleural effusion develops
2. fibrinopurulent - loculations occur
3. organizational - occurs over several weeks, more fibrosis, pleural peel occurs (restricts lung expansion)

Question 4

Empyema: Tx

Answer 4

-start Abx and treat CHF if applicable
-perform thoracentesis if resp or cardiac distress
ABx:
-pip-taz 2.275-4.5 g q5h IV
-or imipenem 0.5-1g IV q6h
-consider MRSA coverage with vanco

Question 5

Lung Abscess

Answer 5

• commonest cause = aspn pna
• other causes: malignancy, wegener, sarcoid, trauma, emboli, sepsis
• takes 7-10d for aspn to become and abscess, usually anaerobes (gm - , peptostreptococcus, prevotella)
• immunocompromised pts: s aureus, e coli, klebsiella, pseudomonas
• signs/sx: weeks of cough, fever, pleuritic c/p, wt loss, night sweats, may have hemoptysis
• complications: hemoptysis, empyema

Question 6

Lung abscess: dx

Answer 6

• CXR: dense consolidation with an air-fluid level inside a thic-walled cavitary lesion
• very dense consolidation
• may require CT

Question 7

-ddx for air fluid level in lung:

Answer 7

-ddx for air fluid level in lung: bullae, pleural fluid collection with bronchopelural fistula, loop of bowel extending through diaphragmatic hernia

Question 8

DDx for cavitary lesion in lung

Answer 8

• AIDS: mycobacteria, fungi, Pneumocystis carinii
• s aureus can have multiple abscesses
• IVDU - pulmonary emboli
• bullae
• TB
• bacterial: anaerobes, s. aureus, gm- , strep pneumo, actinomycosis, nocardiosis
• fungi: coccidio, histo, blastomycosis, aspergillosis, crypto
• parasitic: amebiasis, echinococcosis
• neoplasm
• inflammatory: wegener, sarcoid
• thromboembolism

Question 9

Lung abscess: Tx

Answer 9

• medical management will treat 70-90%
• clinda + flagyl for anaerobes
• percutaneous drainage or thoracotomy with pulmonary resection
• abx for 4-8w
• CXR takes 2mo to clear