Pleuritis Diagnosis and Characteristics

Radiographic Appearance

Pleuritis can present with pleural fluid accumulation that appears as an effusion on chest x-ray, according to the American Thoracic Society, with the fluid typically being exudative and often hemorrhagic, containing variable numbers of erythrocytes, neutrophils, lymphocytes, mesothelial cells, and frequently eosinophils 1
Acute pleuritis may be detected incidentally on radiographs taken for other purposes, appearing as a pleural effusion, as noted by the American College of Chest Physicians 1

On plain chest x-rays, it can be difficult to differentiate between pleuritis with effusion and other causes of pleural effusion, as stated by the British Thoracic Society, with CT scan providing better characterization and may show mild smooth thickening of the parietal pleura in non-infective inflammatory causes of effusion, including pleuritis 3, 4
Ultrasound can help distinguish pleuritis-related effusions from other causes, as inflammatory effusions may show complex internal septations, according to the European Respiratory Society 4

Patients with pleuritis often present with pleuritic chest pain and may have a friction rub on examination, as recommended by the American College of Cardiology 1
The effusion associated with pleuritis may persist for months, present bilaterally, or recur on the same or opposite side, as noted by the American Thoracic Society 1

Thoracentesis is essential for evaluating unexplained pleural effusions seen on imaging, as radiographic features alone have poor sensitivity (0.20-0.48) for determining etiology, according to the British Thoracic Society 4

Asbestos exposure can cause acute pleural effusion that may be mistaken for other causes of pleuritis, as stated by the American College of Occupational and Environmental Medicine, with these effusions possibly being superimposed on long-standing pleural plaques and can lead to diffuse pleural thickening over time 1
Calcified pleural plaques may be visible on imaging in cases of benign asbestos-related pleural effusion, as noted by the European Respiratory Society 4