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pleural fluid

Monday 1 March 2004

Fluid accumulation of pleural effusion

The cellular and biochemical characteristics of pleural fluid vary with either the cause of the fluid accumulation, increased transpleural hydrostatic pressure (congestive heart failure), decreased intravascular oncotic pressure (cirrhosis and nephrotic syndrome), or microvascular injury due to inflammation.

In the absence of microvascular injury, the pleural fluid is transudative and lacks significant concentrations of plasma proteins and inflammatory cells. Inflammation yields exudative effusions, and these can differ substantially in their constituents based on the underlying cause.

The analysis of cell types, plasma proteins, and glucose levels in thoracentesis specimens can help in distinguishing tuberculosis (large numbers of lymphocytes with few mesothelial cells) from rheumatoid disease (large numbers of neutrophils and very low glucose levels), or malignancy (malignant cytology, high protein, and low glucose levels).

Obstruction of lymph flow leads to the accumulation of fluid in the pleural potential space between the lung and the chest wall.


- pleural effusion

  • neutrophilic pleural effusion
  • eosinophlic pleural effusion
  • lymphocytic pleural effusion
  • plasmocytic pleural effusion