ABSTRACT
Pseudochylothorax is an uncommon pleural effusion disease characterized by the presence of cholesterol crystals or high lipid content not resulting from a disrupted thoracic duct. Most of the cases reported so far had been found in patients with long-standing pleural effusion due to a chronic inflammatory disease such as old tuberculous pleurisy or chronic rheumatoid pleurisy. Authors encountered a case of pseudochylothorax in a 45-year-old man who had been treated for tuberculous pleurisy 6 years before his visit to authors' hospital. After that, he had visited the emergency department many times for removal of pleural effusion. The patient's chest X-ray revealed dyspnea and large left-sided pleural effusion. Although a large amount of pleural fluid was removed with a drainage catheter, massive pleural effusion was likely to recur, and the underlying lung was able to fully re-expand. Accordingly, decortication was done, and the patient's symptom was improved without postoperative complications.