[Immunological investigation of late cerebral vasospasm in subarachnoid hemorrhage. (Part 1)].

Although the occurrence of so-called late cerebral vasospasm after subarachnoid hemorrhage (SAH) due to ruptured cerebral aneurysm is well-known, its etiology still remains obscure. This time, the authors investigated the etiology by immunological research. Following results were obtained, Out of 13 cases of SAH due to ruptured cerebral aneurysm, angiographic cerebral vasospasm was observed in 9 cases. In these 9 cases, tendency of decrease in the number of peripheral blood T lymphocytes, depression on the lymphocyte PHA (phytohemagglutinin) and Con A (concanavalin A) response, and tuberculin anergy were found. These results suggest that the depression of cell-mediated immunity function might induce the occurrence of so-called late cerebral vasospasm after SAH.