Pleural Effusion Clinical Presentation

Updated: Oct 15, 2021
  • Author: Kamran Boka, MD, MS; Chief Editor: Guy W Soo Hoo, MD, MPH  more...
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A detailed medical history should be obtained from all patients presenting with a pleural effusion, as this may help to establish the etiology. For example, a history of chronic hepatitis or alcoholism with cirrhosis suggests hepatic hydrothorax or alcohol-induced pancreatitis with effusion. Recent trauma or surgery to the thoracic spine raises the possibility of a CSF leak. The patient should be asked about a history of cancer, even remote, as malignant pleural effusions can develop many years after initial diagnosis.

An occupational history should also be obtained, including potential asbestos exposure, which could predispose the patient to mesothelioma or benign asbestos-related pleural effusion. The patient should also be asked about medications they are taking. [4]

The clinical manifestations of pleural effusion are variable and often are related to the underlying disease process. The most commonly associated symptoms are progressive dyspnea, cough, and pleuritic chest pain.


Dyspnea is the most common symptom associated with pleural effusion and is related more to distortion of the diaphragm and chest wall during respiration than to hypoxemia. In many patients, drainage of pleural fluid alleviates dyspnea despite limited alterations in gas exchange. Drainage of pleural fluid may also allow the underlying disease to be more easily recognized on repeat chest radiographs. Note that dyspnea may be caused by the condition producing the pleural effusion, such as underlying intrinsic lung or heart disease or obstructing endobronchial lesions rather than by the effusion itself.


Cough in patients with pleural effusion is often mild and nonproductive. More severe cough or the production of purulent or bloody sputum suggests an underlying pneumonia or endobronchial lesion.

Chest pain

The presence of chest pain, which results from pleural irritation, raises the likelihood of an exudative etiology, such as pleural infection, mesothelioma, or pulmonary infarction. [23]

Pain may be mild or severe. It is typically described as sharp or stabbing and is exacerbated with deep inspiration. Pain may be localized to the chest wall or referred to the ipsilateral shoulder or upper abdomen because of diaphragmatic irritation. Pain may diminish in intensity as the pleural effusion increases in size and the inflamed pleural surfaces are no longer in contact with each other.

Extrapulmonary symptoms

Other symptoms in association with pleural effusions may suggest the underlying disease process. Increasing lower extremity edema, orthopnea, and paroxysmal nocturnal dyspnea may all occur with congestive heart failure.

Night sweats, fever, hemoptysis, and weight loss should suggest TB. Hemoptysis also raises the possibility of malignancy, other endotracheal or endobronchial pathology, or pulmonary infarction. An acute febrile episode, purulent sputum production, and pleuritic chest pain may occur in patients with an effusion associated with pneumonia.


Physical Examination

Physical findings in pleural effusion are variable and depend on the volume of the effusion. Typically, there are no clinical findings for effusions less than 300 mL. With effusions greater than 300 mL, chest wall/pulmonary findings may include the following:

  • Dullness to percussion, decreased tactile fremitus, and asymmetrical chest expansion, with diminished or delayed expansion on the side of the effusion: These are the most reliable physical findings of pleural effusion. [24, 25]
  • Mediastinal shift away from the effusion: This finding is observed with effusions greater than 1000 mL. Displacement of the trachea and mediastinum toward the side of the effusion is an important clue to obstruction of a lobar bronchus by an endobronchial lesion, which can be due to malignancy or, less commonly, to a nonmalignant cause, such as a foreign body obstruction.
  • Diminished or inaudible breath sounds
  • Egophony (known as "E-to-A" changes) at the most superior aspect of the pleural effusion
  • Pleural friction rub

Other physical and extrapulmonary findings may suggest the underlying cause of the pleural effusion.

Peripheral edema, distended neck veins, and S3 gallop suggest congestive heart failure. Edema may also be a manifestation of nephrotic syndrome, pericardial disease, or, when combined with yellow nailbeds, the yellow nail syndrome.

Cutaneous changes and ascites suggest liver disease.

Lymphadenopathy or a palpable mass suggests malignancy. [4]