Effective management of refractory chylothorax associated with elderly onset Gorham-Stout disease: A case report.

Gorham-Stout disease (GSD) is a rare vascular disease of lymphatic origin characterized by progressive osteolysis that commonly causes chylothorax owing to the leakage of lymphatic fluid from dissolved bones. We report a case of refractory chylothorax that was diagnosed as elderly onset GSD and treated successfully using multidisciplinary approaches. A 78-year-old male presented with persistent cough and shortness of breath caused by massive left pleural effusion. Thoracentesis and pleural biopsy revealed an initial diagnosis of idiopathic chylothorax. The patient underwent continuous thoracic drainage and several percutaneous thoracic duct embolization with subcutaneous octreotide acetate injection and a low-fat diet. Thoracoscopic surgery was performed to control the secondary empyema through the drain tube and repair the pleural lesions with lymphatic leakage. A sufficient decrease in pleural fluid volume allowed temporary removal of the thoracic drainage tube. However, thoracic drainage was resumed for refractory chylothorax when the patient gradually developed neck pain after three months. Computed tomography, magnetic resonance imaging, and bone scintigraphy revealed growing osteolytic lesions in the cervical and thoracic spine regions, and biopsy demonstrated numerous dilated thin-walled capillary structures with lymphocyte infiltrates. After diagnosing GSD and introducing sirolimus, the patient's symptoms improved, and thoracic drainage was discontinued. Multidisciplinary treatments successfully halted disease progression for over a year. The case report emphasizes the systematic examination to identify rare etiology in refractory chylothorax treatment.