From the Guidelines
Bilateral small pleural effusions typically indicate a systemic cause, such as congestive heart failure, cirrhosis, or renal failure, which leads to the accumulation of fluid in the pleural space of both lungs.
Key Points
- The presence of bilateral small pleural effusions suggests a transudative effusion, which is usually caused by an imbalance of hydrostatic and oncotic pressures [ 1 ].
- Chest radiographs can detect pleural effusions greater than 75 mL on the lateral view and greater than 175 mL on the frontal view, while thoracic ultrasound can detect as little as 20 mL of pleural fluid [ 1 ].
- In patients with end-stage renal failure (ESRF), bilateral pleural effusions are often caused by fluid overload, and treatment typically involves aggressive medical management or renal replacement therapy (RRT) [ 1 ].
- In cases where the aetiology is unclear, cross-sectional imaging may be necessary to rule out pleural infection or malignancy [ 1 ].
- The management of bilateral small pleural effusions depends on the underlying cause, but may involve serial thoracocentesis, indwelling pleural catheters (IPCs), or talc pleurodesis in refractory cases [ 1 ].
From the Research
Definition of Bilateral Small Pleural Effusions
Bilateral small pleural effusions refer to the accumulation of small amounts of fluid in the pleural space on both sides of the lungs.
- This condition can be difficult to diagnose using imaging methods such as chest x-rays and ultrasound 2.
- The term "pleural effusion" should only be used in cases of pleural involvement or illness, while "pleural fluid" refers to the normal condition of the pleural space 2.
Causes and Diagnosis
The causes of bilateral pleural effusions can be varied, and in most cases, the effusions have the same cause 3.
- However, in rare cases, there can be two separate causes, known as Contarini's syndrome 3, 4.
- Diagnosis of pleural effusion involves determining its etiology, and thoracocentesis should be performed for new and unexplained pleural effusions 5.
- Laboratory testing and imaging studies can help distinguish between transudative and exudative effusions, and identify the underlying cause of the effusion 5.
Treatment and Management
Treatment of bilateral pleural effusions depends on the underlying cause and may involve drainage of the fluid, treatment of the underlying medical disorder, or pleurodesis to prevent recurrence 5.
- In some cases, treatment with immunomodulating agents such as intravenous immunoglobulin and cyclosporin may be effective in resolving the effusions 6.
- Management of exudative effusions depends on the underlying etiology, and may involve treatment of the underlying condition, drainage of the fluid, or pleurodesis 5.