Cerebral tissue pulmonary embolization due to head trauma: a case report with immunohistochemical confirmation.

Pulmonary embolization of cerebral tissue as the result of severe head trauma is an uncommon, if not rare, phenomenon, and few cases have been reported in the literature. The authors discuss the case of a 51-year-old male who died six days after suffering extensive head trauma in a motor vehicle collision. At autopsy, white-gray emboli were found in several subsegmental pulmonary arteries. The results of histologic examination with the hematoxylineosin stain gave the impression that the emboli were necrotic cerebral tissue; however, routine special stains for neural tissue produced inconclusive results. Immunohistochemical staining of the emboli with monoclonal mouse anti-human neurofilament protein (Dako Corp., Carpinteria, California) confirmed the cerebral nature of the emboli. To the authors' knowledge, this is the first reported case of pulmonary embolization of cerebral tissue confirmed by immunohistochemistry.