A Rare Case of Right-Sided Chylothorax Following Thoracoscopic Sympathectomy Due to an Anomalous Thoracic Duct.

Chylothorax, despite being a common complication after thoracic surgery, is rare after thoracic sympathectomy, especially on the right side of the thorax. We present a case of a patient who developed a right chylothorax after a thoracoscopic sympathectomy due to the presence of an anomalous thoracic duct located on the right side of the patient's chest. A 37-year-old woman underwent a bilateral video-assisted thoracic sympathectomy for the treatment of primary focal axillary hyperhidrosis. During the postoperative period, there was an excessive discharge of a white, milky fluid through the chest drain, with an average daily output of 350-500 mL/day. Chylothorax was confirmed after laboratory analysis, which revealed a triglyceride level of 146 mg/dL. Due to the worsening appearance of the pleural fluid and the increased drainage volume, reaching 1,000 mL, the patient underwent exploratory videothoracoscopy. During the procedure, a lymphatic fistula was visualized in the region of the sympathetic chain, allowing the identification of an anomalous thoracic duct on the right side of the patient's thorax. The anomalous thoracic duct was dissected, with inferior and superior clipping of the duct. The patient remained stable and was discharged three days after the procedure. This case report describes an especially rare presentation, being one of the few cases of right chylothorax after thoracoscopic sympathectomy described in the literature to date. This study points out that, despite thoracic sympathectomy being considered a safe surgical procedure, unusual complications, such as chylothorax, and anatomical variations of the thoracic duct must be considered.