Ruptured infected mediastinal teratoma complicated with pericarditis and cardiac tamponade: A case report

Teratomas are the most prevalent type of mediastinal germ cell tumor. While most mediastinal teratomas remain asymptomatic, on rare instances it may rupture into the pericardium, leading to pericardial effusion and cardiac tamponade, which is associated with high mortality rates. In this report, we present a child with a large anterior mediastinal teratoma that ruptured into the pericardial cavity, resulting in severe pericarditis and cardiac tamponade. A 12-year-old male presented with syncope and tachycardia, which prompted further investigation. Chest radiography revealed a lobulated and homogeneous mass in the anterior mediastinum. Subsequent thoracic computed tomography (CT) scans revealed a complex anterior mediastinal mass exhibiting cystic and solid components, with calcification, fatty elements, and a significant pericardial effusion. Pericardiocentesis, performed to alleviate the tamponade, evacuated a large volume of purulent fluid. Surgical intervention was pursued, and a total resection of the mediastinal mass was performed using a transthoracic approach with a cardiac window into the pleural cavity. The resected mass was a ruptured multicystic structure filled with pus and composed of muscle and tendon tissues. Microscopic examination confirmed the diagnosis of a mature teratoma. Following the procedure, the patient experienced a complete recovery without any complications. The rupture of an infected mediastinal mature teratoma into the pericardium is an uncommon occurrence, yet it poses a significant threat with a heightened risk of mortality. Timely surgical intervention is imperative to minimize the complications associated with rupture.