From the Guidelines
Pleural effusions associated with pulmonary embolism (PE) and neoplastic disease are typically exudative, with the majority of PE-related effusions being exudates (80%) and nearly all neoplastic effusions being exudative. The type of pleural effusion associated with PE can vary, with 80% being exudates and 20% being transudates, as noted in the BTS guidelines for the investigation of a unilateral pleural effusion in adults 1. In contrast, neoplastic diseases are more likely to cause exudative pleural effusions due to increased vascular permeability, direct tumor invasion, or lymphatic obstruction, as discussed in the management of malignant pleural effusions 1. Key characteristics of pleural effusions associated with PE and neoplastic disease include:
- Exudative effusions are more common in both conditions
- Bloodstained effusions are common in PE, with 80% of effusions being bloodstained 1
- A pleural fluid red blood cell count of more than 100,000/mm3 is suggestive of malignancy, pulmonary infarction, or trauma 1
- Neoplasms often cause exudative effusions due to increased vascular permeability, direct tumor invasion, or lymphatic obstruction 1. Recent guidelines, such as the ERS/EACTS statement on the management of malignant pleural effusions 1 and the ATS/STS/STR clinical practice guideline on the management of malignant pleural effusions 1, emphasize the importance of palliative care and symptom management in patients with malignant pleural effusions, and highlight the need for individualized treatment approaches.
From the Research
Type of Pleural Effusion Associated with Pulmonary Embolism (PE) and Neoplastic Disease
- The type of pleural effusion associated with pulmonary embolism (PE) is usually an exudate, occasionally transudative 2, 3, 4, 5.
- Pleural effusions due to pulmonary embolism are typically small, occupying less than one-third of the hemithorax in 90% of cases 3.
- The presence of pleuritic chest pain in a patient with a pleural effusion is highly suggestive of pulmonary embolism 2, 4.
- Neoplastic disease, particularly lung cancer, is also a common cause of pleural effusion, with malignant pleural effusions being exudates 6.
Characteristics of Pleural Effusions in PE
- Pleural effusions secondary to PE can be found in around one-third of all cases with PE 5.
- They are small, mostly unilateral, often but not always hemorrhagic 5.
- They are always exudates with a predominance of neutrophil cells 5.
- The biochemical characteristics of pleural effusions in PE include a total protein level of 45.70±7.25 gr/l and an LDH effusion/sera ratio bigger than 0.6 in most cases 5.
Diagnosis and Treatment
- Spiral computed tomography pulmonary angiography (CTPA) is the best way to evaluate the possibility of pulmonary embolism in a patient with a pleural effusion 3, 4.
- The treatment protocol for a patient with pleural effusion secondary to pulmonary embolism is the same as that for any patient with pulmonary embolism, including anticoagulation therapy 3, 4.
- The presence of bloody pleural fluid is not a contraindication for the administration of anticoagulant therapy 4.