Patient: Description of condition (onset, main symptoms, hospital visited, etc.): Chest tightness, chest pain, weakness and feeling of breathlessness after examinations in July, and examination at the hospital revealed a medium amount of pleural effusion on the left side. Doctor: Acute pleurisy in young people, common causes: 1, common bacterial pleurisy. 2, tuberculous pleurisy. Can perform thoracentesis to place a central venous catheter to drain the pleural fluid, while doing related tests, such as routine pleural fluid, biochemical, pleural fluid bacterial culture, pleural fluid to find antacid bacilli, blood tuberculosis antibody test, etc., if the diagnosis is still not confirmed, diagnostic anti-tuberculosis treatment is feasible, that is, anti-tuberculosis treatment for 2 weeks to see the reduction of pleural fluid.