The Art of Pleural Fluid Analysis

Abstract

Although a pleural effusion (PE) is a common condition in clinical practice (with a prevalence of slightly > 400 patients/100,000), a definitive diagnosis is not established in approximately 20% of cases. In the classic publications, thoracentesis provided a definitive or presumptive diagnosis in 73% of cases, although it is estimated that today this percentage could reach 95%. An undiagnosed PE is defined as one that remains of unknown origin after performing complete pleural fluid analysis (nucleated cell counts with differential diagnosis, biochemistry, culture, cytology, and flow cytometry). The aim of this paper is to review the difficulties that may be encountered when attempting to establish the cause of a PE. The reason for this diagnostic dilemma may be an atypical clinical or radiologic presentation or falsepositive or false-negative results. Furthermore, the limited frequency of some PEs is often not considered when determining the differential diagnosis.

Predicting malignant and tuberculous pleural effusions through demographics and pleural fluid analysis of patients

“…Various biological markers have been determined in several studies to help in the differential diagnosis of pleural exudates (10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21), but in all of them the result of each marker has been used individually. Only one study has taken their combined use into account, although the number of cases has been small and the results obtained were inconclusive (22).…”

Selected Disorders of the Respiratory System

“…Pleural effusions are very common in clinical practice, with an estimated prevalence of 400 cases/100,000. A plethora of disease processes can cause pleural effusions with the most common being congestive heart failure, hepatic cirrhosis, pulmonary infections, and malignancy [10].…”

“…While history and physical examination can provide clues to the causes of pleural effusions, determination of the exact etiology can be very difficult. Thoracentesis and pleural fluid analysis (PFA) are the next steps in the evaluation process; PFA can lead to a definitive or presumptive diagnosis in approximately 95% of cases [10].…”

“…Additionally, an increase in negative pressure in the pleural space can also lead to these types of effusions. Congestive heart failure and cirrhosis are the two most common causes of transudative effusions [10]. Pleural effusions associated with CHF tend to be bilateral.…”

Left ventricular puncture during thoracentesis

“…Thoracentesis is a procedure that has diagnostic and therapeutic value for pleural effusions 1. Well-known complications following this procedure include pain, bleeding, pneumothorax and infection.…”