How do I diagnose a patient with right pneumothorax (pneumo-thorax) or more specifically right empyema (em-py-e-ma)?

From the Guidelines

To diagnose a patient with right empyema, begin with a thorough clinical assessment and imaging, prioritizing a chest CT scan with IV contrast as the initial imaging modality, as recommended by the most recent guidelines 1.

Clinical Assessment

Start by looking for symptoms such as fever, cough, chest pain, and dyspnea, particularly if they're more pronounced on the right side. A comprehensive medical history and physical examination are crucial to define the severity of the condition and to exclude other potential sources of infection 1.

Imaging

Order a chest X-ray, which may show pleural effusion, air-fluid levels, or loculations on the right side. However, for better visualization of the pleural space and to identify loculations, pleural thickening, or adjacent lung pathology, a chest CT scan with IV contrast is preferred 1. The CT scan findings most commonly associated with the diagnosis of empyema include pleural enhancement, pleural thickening, loculation, extrapleural fat proliferation, and increased attenuation of the extrapleural fat.

Diagnostic Procedures

Thoracentesis is essential for definitive diagnosis - aspirate pleural fluid and send it for analysis including cell count, Gram stain, culture, pH, protein, LDH, and glucose. Empyema typically shows purulent fluid with pH <7.2, glucose <60 mg/dL, LDH >1000 IU/L, and positive cultures. Ultrasound guidance for thoracentesis improves safety and yield, especially with loculated effusions. Blood cultures should also be obtained before starting antibiotics, as they may identify the causative organism in 40% of cases.

Further Diagnosis and Treatment

If thoracentesis is inconclusive but empyema is still suspected, video-assisted thoracoscopic surgery (VATS) may be necessary for both diagnosis and treatment. Early diagnosis is crucial as delayed treatment can lead to increased morbidity, longer hospital stays, and potentially the need for more invasive interventions. The recent guidelines from the American College of Radiology 1 emphasize the importance of appropriate imaging and diagnostic procedures in the management of pleural effusion or pleural disease.

From the Research

Diagnosing Right Emphyema

To diagnose a patient with right emphyema, the following methods can be used:

• Imaging tests such as computed tomography (CT) or ultrasound (US) to confirm the diagnosis and facilitate drainage 2, 3, 4, 5, 6
• Chest radiographs to distinguish empyema from a transudative pleural effusion 3, 4
• CT findings such as pleural enhancement, pleural thickening, and thickening of extrapleural fat to suggest empyema 2, 4, 5
• Ultrasound findings such as hyperechoic collections with septae to suggest empyema 2, 6

Imaging Characteristics

The imaging characteristics of empyema include:

• On CT: oblong fluid collection with smooth inner margins, compression and displacement of surrounding lung and airways, pleural enhancement, and pleural thickening 2, 4, 5
• On US: hyperechoic collections with septae, complex (nonanechoic) effusions 2, 6
• On chest radiographs: encapsulated effusion in an atypical position 4

Diagnostic Criteria

The diagnostic criteria for empyema include:

• Presence of pus or fluid with high protein and lactate dehydrogenase levels
• Imaging findings suggestive of empyema, such as those mentioned above
• Clinical symptoms such as fever, chest pain, and cough 2, 3, 4, 5, 6