THORACIC AND RESPIRATORYDISORDERS■ K. pneumoniae
■ Gram-negative bacilli
■ Streptococcus pyogenes
■ Nocardia asteroids
■ Actinomycessp.
SYMPTOMS/EXAM
Indolent course of fever, chest pain, weight loss, and night sweats
DIFFERENTIAL
The differential diagnosis of the cavitary lung lesion includes fungal infec-
tions, neoplasm, Wegener granulomatosis, sarcoidosis.
DIAGNOSIS
■ CXR: Usually confirms the presence of cavitary lesion with air-fluid levels
■ Chest CT: May occasionally be needed to confirm cavitation
TREATMENT
Piperacillin/tazobactam or clindamycin
Empyema
Defined as pus in the pleural space or pleura fluid with presence of organisms
on Gram stain
Risk factors for empyema include:
■ Pneumonia with parapneumonic effusion (most common)
■ Penetrating trauma
■ Esophageal perforation/rupture
■ Presence of hemothorax, hydrothorax, or chylothorax
PATHOPHYSIOLOGY
The infection generally progresses through three stages:
■ Exudative stage: Free-flowing fluid present
■ Fibrinopurulent stage: Fibrin strands develop →loculations
■ Organizational stage: Thick pleural peel present
■ Identification and treatment in the exudative stage is essential to ensure
good patient outcome.
SYMPTOMS/EXAM
■ Presence of risk factor, eg, recent pneumonia
■ Persistent fevers, dyspnea, pleuritic chest pain, and cough
■ Dullness to percussion and ↓breath sounds over the effusion
DIAGNOSIS
■ CXR:Can confirm the presence of pleural effusion
■ Decubitus CXR:To determine if fluid is free-flowing or loculated
■ Pleural fluid evaluation. Findings consistent with empyema include:
■ Aspiration of frank pus
■ Pleural fluid pH <7.2
■ Positive Gram stain or culture
■ Chest CT:To further delineate underlying pathology and evaluate extent
of loculations and/or pleural peel, as needed