A 62-year-old woman with bilateral pleural effusions and pulmonary infiltrates caused by extramedullary hematopoiesis.

A 62-year-old female presented with a 1-month history of irritating cough and increasing dyspnea. A chronic idiopathic myelofibrosis had been diagnosed 5 years ago. CT of the chest and abdomen showed bilateral pleural effusions with a thickened pleura, nodular infiltrations in both lungs, enlarged intraabdominal lymph nodes and splenomegaly. Pleuroscopy (medical thoracoscopy) on the left side revealed dense tumorous nodules mainly on the posterior chest wall pleura, but also on the diaphragm and the lung. Biopsies taken from the chest wall pleura revealed extramedullary hematopoiesis (EMH) with abnormal megakaryocytes as well as myeloid and erythroid precursors. After unsuccessful tetracycline pleurodesis, talcum slurry was instilled via the chest tube without recurrence of the pleural effusion. Furthermore, treatment with hydroxyurea was started, and the disease regressed and then remained stable over the next 24 months. In conclusion, the pleuropulmonary findings were caused by EMH due to chronic idiopathic myelofibrosis. The definite diagnosis was established by pleuroscopy followed by successful pleurodesis with talc slurry, after tetracycline pleurodesis had failed.