Causes of chylothorax and pseudochylothorax
Chylothorax:

  • Trauma:

  • Neoplasm:

  • Miscellaneous:

  • Idiopathic (about 10%)

thoracic surgery (especially if involving posterior mediastinum, for example, oesophagectomy), thoracic injuries
lymphoma or metastatic carcinoma
disorders of lymphatics (including lymphangioleiomyomatosis), tuberculosis, cirrhosis, obstruction of the central veins, chyloascites
Pseudochylothorax:

  • Tuberculosis

  • Rheumatoid arthritis