SYNOPSISThe activity of blood clotting factors has been investigated in cerebrospinal fluid. No cephalin-like activity was found in cerebrospinal fluid but prothrombin activity averaged about 0 5 % of normal plasma activity. The activity of factor VII was negligible in almost all cases. The activity of antihaemophilic factors showed great variation but in the majority of cases it did not exceed 1 % of normal plasma activity. High activity for factor V was found in almost all samples of cerebrospinal fluid.Many papers have been published on the electrophoretic pattern of the proteins and on enzymes in cerebrospinal fluid but the activity of blood-clotting factors in cerebrospinal fluid has not been sufficiently investigated. The presence of substances accelerating the coagulation of normal human plasma in cerebrospinal fluid has been demonstrated by Kafka (1945Kafka ( , 1950Kafka ( , 1955, and, according to Putnam (1937), the basic abnormality of multiple sclerosis is to be found in disturbances of the clotting mechanisms. Persson (1956) discovered a platelet-agglutinating substance in the cerebrospinal fluid in multiple sclerosis and in cerebral syphilis only, a fact which Feldman, Izak, and Nelken (1957) could not confirm. Albright, Kupfer, and Kinne (1959) found that neither normal spinal fluid nor that of multiple sclerosis patients had any thromboplastic activity in blood or tissue. Nour-Eldin (1959) considers cerebrospinal fluid to be inactive in the clotting processes although Kundu and Chaterjea (1961) showed the existence of an active substance in the thromboplastin generation test in cerebrospinal fluid. Antithrombic activity of normal and pathological cerebrospinal fluid was recently discovered by Gaertner, Lisiewicz, and Caen (1961).The purpose of this paper is to examine the activity of the clotting factors in cerebrospinal fluid in various patients. The activity of factor V was surprisingly high in almost all samples tested. Fresh cerebrospinal fluid from 68 patients in the Neurological Department was collected by lumbar puncture. The interval between lumbar puncture and laboratory investigations never exceeded three hours. In 10 patients no neurological abnormalities were found, and samples of cerebrospinal fluid taken from them were considered normal. Of the remaining patients, 16 had suffered a cerebral haemorrhage, 10 had encephalitis, six had primary tumours of the brain or spinal cord, four had epilepsy, five had disseminated sclerosis, three had muscular dystrophy, and seven had various inflammatory diseases of the central or peripheral nervous system. Each of the remaining seven patients was suffering from a different disease of the central nervous system. All samples of the investigated cerebrospinal fluid showed normal protein levels (33 to 39 mg. %). Samples containing blood were not tested.Plasma from patients with congenital haemorrhagic diseases was supplied by Dr. H. Cetnarowicz.
METHODSThe clotting factors in cerebrospinal fluid were determined using one-stage methods, and its cepha...