Posttraumatic active bleeding of mediastinal mixed vascular malformation: a case report.

A case of an actively bleeding mediastinal mass in a 4-year-old boy who sustained multitrauma is described. A computed tomography (CT) scan of the chest upon admission demonstrated a mediastinal mass, which enlarged significantly as seen by repeat CT scan at 3 days with a concomitant drop in serum hemoglobin levels. The lesion was excised, and pathological examination established the diagnosis of a lymphatic-venous malformation containing bloody fluid. Lymphatic-venous malformations are rare vascular malformations and are usually found in the head and neck and less commonly at other sites. Spontaneous bleeding is a known complication, and there are few reports describing posttraumatic hemorrhage. Our case is the first description in the English medical literature of a posttraumatic bleeding mediastinal mixed vascular malformation and includes sequential CT scans illustrating the dynamic nature of hemorrhage.