Neuropathologic Features and Underlying Medical Disease States of Spontaneous Subdural Hematomas in Adults: A Hospital Autopsy Case Series From a Single Tertiary Center.

Context.—: Spontaneous (nontraumatic) subdural hematomas have been reported yet have not been well studied.

Objective.—: To identify the neuropathologic features of acute spontaneous SDHs (ASSDHs) and their associated medical conditions.

Design.—: A retrospective study of 235 autopsy cases of SDH was conducted. Review of demographics, underlying medical conditions, and coagulation profile as well as gross and histopathologic examination of the brain and other organs were performed.

Results.—: Among the 32 cases of ASSDH, 5 cases (15.6%) had severe hemorrhage and 4 (12.5%) demonstrated brain herniation. Twenty-two cases (68.8%) had concurrent but nonconnecting subarachnoid hemorrhage or intraparenchymal hemorrhage. The most common underlying medical condition was thrombocytopenia (n = 21; 65.6%), followed by immunosuppression (n = 15; 46.9), bloodstream infections or sepsis (n = 12; 37.5%), hypertension (n = 13; 40.6%), and coronary artery disease (n = 12; 37.5%). Many patients with thrombocytopenia or immunosuppression had underlying malignancies, with leukemia being the most common type (n = 11; 34.4%). The use of circulatory devices or hemodialysis was noted in a significant portion of ASSDH cases. In terms of coagulation factors, most of our ASSDH patients had normal prothrombin time and activated partial thromboplastin time, but abnormal platelet count and D-dimer levels.

Conclusions.—: ASSDHs can be severe and are often associated with subarachnoid hemorrhage and/or intraparenchymal hemorrhage. The causes of ASSDH are limited to certain underlying medical conditions that ultimately lead to bleeding tendency. Autopsies are helpful in determining the etiology. Given their association with abnormal platelet count, correcting platelet deficiencies is a potential preventive measure for ASSDHs.