MANAGEMENT OF UNDIAGNOSED PERSISTENT PLEURAL EFFUSIONS

Difficult to diagnose pleural effusions are not uncommonly encountered in clinical practice. We define these effusions as those that remain undiagnosed after initial thoracentesis and repeat thoracentesis with pleural biopsy. Tuberculosis and malignancy are often found to be the underlying causes when a diagnosis is ultimately made, but other cause s, including pulmonary embolism and intra-abdominal conditions, need t o be considered as potential causes of the difficult to diagnose effus ions. In selected cases, presumptive treatment of tuberculosis is indi cated whereas in others, a decision must be made either to obtain a de finitive diagnosis by invasive surgical procedures or to follow the pa tient with careful observation and watchful waiting.