[A case of primary effusion lymphoma with elevation of ADA activity in pleural effusion].

A 74-year-old man was referred to our hospital with complaint of dyspnea and left pleural effusion. The pleural effusion was exudative and lymphocytic with elevation of adenosine deaminase (ADA). Antitubercular agents were administered on a diagnosis of tuberculous pleuritis, but the pleural effusion did not improve. After he had been followed up with diuretic agents during about 2 years, he suffered cardiac tamponade and right pleural effusion. We diagnosed primary effusion lymphoma based on the cytology findings of the pleural effusion. The measurement of ADA activity in pleural effusions was useful for diagnosis of tuberculous pleuritis, but not only tuberuculous pleuritis but also lymphoma or other diseases can show elevation of ADA activity in pleural effusions.