Subarachnoid hemorrhage of unknown etiology

The diagnosis of spontaneous subarachnoid hemorrhage (SAH) alerts the physician to the possibility of a potentially life-threatening condition. Approximately 80% of patients with a spontaneous SAH will turn out to have an intracranial aneurysm or an intracranial AVM. Subarachnoid hemorrhage is also a well-recognised element of several diverse medical complications or diseases. Acknowledging these rare causes of SAH, 7-27 percent of patients who have suffered SAH will demonstrate no source of such hemorrhage. In a series of 413 patients with signs and symptoms of SAH, 80 patients had SAH of an unknown etiology. The dominant symptoms were sudden attacks of headaches and vomiting; the majority of patients were females in a Hunt/Hess clinical grade I or II; computed tomography scan revealed a high percentage (34.21%) of patients who had no discernible subarachnoid blood visible on a postictal brain CT scan. There was no recurrent hemorrhage among our patients. All patients were treated by bed rest, hydration, antiedematous therapy and some of them received nimodipin. There was one death unrelated to the stroke and low morbidity. So one can conclude that patients with SAH of an unknown etiology have a markedly better prognosis than patients with a ruptured intracranial aneurysm.