Abstract
Aneursymal subarachnoid haemorrhage is frequently complicated by non-haemorrhagic deterioration. HLA typing was studied in a group of 40 patients who had sustained an aneurysmal subarachnoid haemorrhage in order to assess its ability to identify those who are likely to experience non-haemorrhagic deterioration. The antigen HLA-B7 appeared to be associated with an increased likelihood of this event supervening. Conversely, the antigen HLA-DR3, seemed to exert a "protective" influence.