Sex steroid hormones in the pathogenesis of chronic subdural haematoma.

In order to verify whether hormonal factors could be involved in the pathogenesis of Chronic Subdural Haematoma (CSDH), based on clinical and epidemiological demonstration of higher incidence of this disease in male patients and particularly in those with high urinary estrogen values, Estradiol (ER) and Progesterone (PR) Receptors were studied in the Haematoma External Membrane (HEM) in 18 male and 7 female CSDH patients. The observed higher incidence of ER and PR in male rather than in female patients (73% vs 27% and 72% vs 28% for male and female patients respectively), and the higher concentration of ER in the HEM of male rather then female patients (55 +/- 15 S.E. vs 13 +/- 7 S.E. fmol/mg protein) suggest that this pathological process, which affects individuals whose gonadal activity is quiescent, is mainly dependent upon hormonal local effect played by estrogen compounds on the HEM of the male patients. In this sex, in fact, whose tissues are not usually adapted to an estrogen action, the effect of estrogens on a responsive tissue such as the newly-vascularized HEM could lead to an increased formation of tissue Plasminogen Activator (t-PA), a compound that, escaping into the subdural collection, could maintain a local hyperfibrinolysis with formation of Fibrinogen Degradation Products (FDP). Therefore local hyperfibrinolysis enhanced by steroid hormones and the subsequent CSDH may perhaps be influenced by the prophylactic or adjuvant treatment with inhibitors either of the aromatase activity or of the estrogen action at receptor level.