title: Free protein S deficiency: a possible association with cerebrovascular occlusion.
abstract: A deficiency of free protein S, known to increase the risk of peripheral venous thrombosis, has not been well described in patients with cerebrovascular disease. In a pilot study of 35 patients with symptomatic cerebrovascular disease, using a qualitative crossed immunoelectrophoresis assay we found eight patients with a free protein S deficiency. A Laurell immunoelectrophoresis assay was used to quantify the percentage of free protein S after removal of the inactive protein S C4b-binding protein complex by precipitation with polyethylene glycol 8000. In a quantitative study of 103 patients with cerebrovascular disease, 21 had a free protein S that was less than 20% of the average normal total protein S concentration (normal range 20-40%); 19 had suffered cerebral infarction and the other two had suffered intracranial hemorrhage. The frequency of free protein S deficiency in this group of stroke patients was far higher than the expected prevalence in the general population.
authors.affiliation: Neurological Institute, New York, NY 10032.
authors.forename: R L
authors.initials: RL
authors.lastname: Sacco
authors.forename: J
authors.initials: J
authors.lastname: Owen
authors.forename: J P
authors.initials: JP
authors.lastname: Mohr
authors.forename: T K
authors.initials: TK
authors.lastname: Tatemichi
authors.forename: B A
authors.initials: BA
authors.lastname: Grossman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001157:Arterial Occlusive Diseases / Q000378:metabolism*; D002533:Cerebral Angiography; D002543:Cerebral Hemorrhage / Q000097:blood; D002544:Cerebral Infarction / Q000097:blood; D002561:Cerebrovascular Disorders / Q000097:blood / Q000175:diagnosis / Q000378:metabolism*; D006023:Glycoproteins / Q000172:deficiency*; D006801:Humans; D007123:Immunoelectrophoresis, Two-Dimensional; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D009994:Osmolar Concentration; D017293:Protein S; D014057:Tomography, X-Ray Computed
chemical_list: D006023:Glycoproteins; D017293:Protein S