Transudative chylothorax in a patient with pulmonary hypertension

Introduction: Chylothorax is defined by the presence of chyle in the pleural space. Transudative chylothorax has been reported between %15 - %32 of all chylothorax cases. In this report, we present a case of transudative chylothorax possibly developed from pulmonary hypertension due to cardiac valvular insufficiency and right heart failure. Case Presentation: A seventy years old, female patient admitted to our hospital with symptoms of dyspnea, right-sided chest pain for last 6 months. On chest radiography, pleural effusion covering nearly half of the right hemithorax was observed. Closed chest tube drainage was performed for relieving excessive pleural effusion. Since the color of pleural effusion appeared to be milky, pleural effusion was evaluated biochemically for chylothorax. Triglyceride level was found three fold higher than normal, but pleural effusion was transudative. Discussion: Chylothorax does not always meet the exudative criteria. Transudative form has been reported between %15-32 in several studies due to various pathologies. Since now, only two cases of transudative chylothorax due to pulmonary hypertension secondary to right heart failure have been reported. The possible mechanism for transudative chylothorax is poorly understood. Although very rare, evaluation of transudative pleural effusion for chylothorax should be considered in any patient with pulmonary hypertension with pleural effusion in clinical practice.