[A case of post-traumatic eosinophilic pleural effusion improved by direct infusion of corticosteroid into the pleural space].

A 49-year-old man was admitted with non-productive cough and left chest discomfort. About one month prior to the admission, he suffered a non-penetrating injury to the left anterior chest. Although rib fracture or pleural effusion was not reported, left chest discomfort and non-productive cough progressed gradually. Chest X-ray film and chest CT scan on admission showed left massive pleural effusion. Close examination revealed a marked increase of eosinophils in the pleural effusion (77% of total cell counts). Because malignancy, parasitic disease, and collagen disease were differentiated, we diagnosed this case as post-traumatic eosinophilic pleural effusion, and decided to administers corticosteroid therapy; hydrocortisone 300 mg was infused into the left pleural space. Seven days after the treatment, the pleural effusion and peripheral eosinophilia had completely disappeared. This case suggests that direct infusion of corticosteroid into the pleural space provides greater drug availability in the treatment of post-traumatic eosinophilic pleural effusion related to immunological reaction of the pleura. The indication and dosage of corticosteroids should be established, however, because there have been some reports of cases of improvement without any special treatment.