Posted by / 23-Jul-2020 03:05

Samples should ideally be collected into heparin tubes to prevent clot formation.Samples for glucose should be adequately preserved with fluoride.Normally, they contain a small amount of fluid that is an ultrafiltrate of plasma.When production and resorption of this ultrafiltrate are not balanced, fluid may accumulate, resulting in an effusion.All samples should be centrifuged prior to analysis.The serous body cavities are mesothelial lined potential spaces surrounding the lungs, heart and abdomen.

If the pleural fluid protein is between 25 and 35 g/L: the pleural fluid is an exudate if pleural fluid LDH greater than 66% of the upper limit of normal of the serum LDH method.The protein concentration of an exudate usually exceeds 3 g/d L.Exudate LD activity is greater than 0.67 times the upper limit of normal for serum.To distinguish exudates from transudates if the patient’s serum total protein is normal and the pleural fluid protein is less than 25g/L the fluid is a transudate.If the pleural fluid protein is greater than 35g/L the fluid is an exudate.


In this prospective study of 150 pleural effusions, the utility of pleural-fluid cell counts, protein levels, and lactic dehydrogenase (LDH) levels for the separation of transudates from exudates was evaluated.