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We report clinical findings, risk factors and neurological and cognitive long-term outcome in three Italian children aged 7, 8 and 5, respectively, who experienced cerebral venous sinus thrombosis (CVST). All children presented with headache, associated to nausea, vomiting and papilloedema. None suffered from epileptic seizures. In two of them a paresis of the sixth cranial nerve with diplopia was found. Diagnosis was confirmed by magnetic resonance imaging angiography (angio MRI) in all cases. In all patients plasma levels of protein C, protein S, antithrombin III (AT III), antiphospholipid antibodies (ApA) and homocysteine were detected. Furthermore, factor V Leiden mutation, prothrombin mutation G20210A and MTHFR mutation were searched for. A Protein C reduction was detected in all patients at onset; this finding, however, was not confirmed at follow-up in all of them. At one-year follow-up, neurological examination was normal in all children and neuropsychological assessment, aimed at excluding linguistic and non-linguistic cognitive deficits, revealed normal performances in two of them. In the third child, cognitive assessment confirmed a previously diagnosed developmental dyslexia.

This collaborative study, organized by the Hemostasis Subcommittee of C.I.S.M.E.L., evaluated the accuracy, precision, and comparability of the following six widely used fibrinogen assays: total clottable fibrinogen (Blombäck and Blombäck), clotting time (Von Clauss), turbidimetry (Ellis and Stransky), Chromotime System, prothrombin time (PT)-derived, and radial immunodiffusion (RID). The same frozen samples, with normal and high contents of fibrinogen, were examined in four laboratories. The methods were calibrated with an internal standard whose fibrinogen content was determined gravimetrically. Both the Von Clauss and the RID methods were reliable, accurate, and precise, if adequate calibration was used. The PT-derived method was highly reproducible, but had some problems with accuracy. We demonstrate that an adequate calibration procedure is indispensable for reliable fibrinogen measurements whatever method is used. Because neither the calibration procedures proposed by the manufacturers nor the use of lyophilized commercial plasmas is adequate for this purpose, we urge that an international standard for fibrinogen measurement be promptly established.

The constantly workload increase has led to the development of Computerised Decision Support Systems (CDSS) for a better management of patient care. Many clinical situations have been investigated to verify the utility of CDSS: few have demonstrated stable effects. One area where success has been reported is the field of oral anticoagulation management. CDSS system has demonstrated to be able to improve the treatment quality in comparison to manual method. In the future scenario of oral anticoagulant management CDSS will have a pivotal part, the constant increase of patients number and their pressure on thrombosis centres had led to the development of alternative models for delivery OAT: Primary care, General Practitioner, Patient self testing and self management and the use of CDSS has been central to the decentralisation process and may be useful in maintaining the efficacy and quality of anticoagulant control. GP with the aid of CDSS are able to deliver OAT as well as expert physician of Thrombosis Centre in terms of time spent by patient in therapeutic range.

We carried out a prospective, randomized trial to test whether a computer-based decision support system to initiate and maintain oral anticoagulant (OA) treatment can improve the laboratory quality of therapy.Two separate sets of patients on oral anticoagulants, in five Italian anticoagulant clinics, were studied: 335 patients in the first three months of treatment (stabilization phase), 916 patients (775 patient-years) beyond the third month of treatment (maintenance phase). Patients were randomized to a computerized system, which included algorithms able to suggest OA dosing and to schedule appointments (computer-aided dosing) or to an arm in which OA were prescribed by the same teams of expert physicians without such algorithms (control group). Primary outcomes were: A) the percentage of patients reaching a stable state of anticoagulation during each of the first three months of treatment; B) the percentage of time individuals spent within the aimed therapeutic range (maintenance phase).Patients in the computer-aided dosing group achieved a stable state significantly faster (p0.01) and they spent more time within the therapeutic range during maintenance (p0.001) than controls. The favorable effect of computer-aided dosing was mainly due to a reduction of the time spent below the therapeutic range and was associated with an increase of mean INR value, of anticoagulant drug dosage, and with a reduction of the number of appointments per patient (all changes significant: p0.001).The computer decision-aided support improves the laboratory quality of anticoagulant treatment, both during long-term maintenance and in the early, highly unstable phase of treatment, and it also significantly reduces the number of scheduled laboratory controls.

Cerebral venous and sinus thrombosis (CVST) is still considered a severe clinical problem that is difficult to diagnose and manage and is linked to a poor prognosis. Nonetheless, conventional cerebral angiography and magnetic resonance imaging (MRI), or more recently, MR angiography allow a more rapid and precise diagnosis, and prognosis has improved with the use of anticoagulant treatment. We report 23 cases of CVST consecutively admitted to the Institute of Neurology of the University of Parma during the period 1990-1997. In all cases diagnosis was confirmed by means of MRI or conventional angiography of brain vessels. Among the patients, 22 were female and 1 was male. In all patients, plasma levels of protein C, protein S, antithrombin III (ATIII) and antiphospholipid antibodies (APA) were evaluated. In 15 of 23 patients, the presence of factor V Leiden mutation was also determined, and found positive in 3 patients (20%). Of the 22 female patients, 15 (68%) were on low-oestrogen (containing less than 50 microg oestrogen) oral contraceptive (OC) treatment. This percentage of OC use by patients with CVST is much higher than that of the rest of the female Italian population. OC use was associated with the presence of factor V Leiden mutation in two cases, with a deficiency of protein C in 1 case and a deficiency of protein S in another.Whether low-oestrogen Ocs may induce cerebral thromboembolic events is an open matter. According to our data, it may be argued that Ocs, even if at low oestrogen content, represent a major risk factor for CVST. The use of Ocs, as is the case for systemic venous thromboembolic events, may further increase the risk of CVST in women carrying the factor V Leiden mutation or other inherited hyperthrombotic conditions.

Heparin administration for operations with extracorporeal circulation (ECC) usually is performed following prefixed, standardized protocols. These regimens secure an adequate level of anticoagulation, hut they often involve prolonged periods of overheparinization associated with an undue risk of hemorrhage. The predictive value of preoperative studies on the anticoagulant effect of heparin was investigated in 10 patients. The study was performed both in vitro and in vivo using the Xa inhibitor assay as an index of the anticoagulation induced by heparin. Adding variable amounts of heparin in vitro to patient’s plasma resulted in straight (at least up to 7 U. per milliliter) and parallel, but not coincident, dose/response curves, so confirming a different individual sensitivity to heparin. Disappearance curves of the anticoagulant effect in plasma following intravenous administration of a single standard dose of heparin in the same patients showed an even greater patient-to-patient variability, with “half-life” times ranging from 30 to 150 minutes. No relationship was found between the two parameters (in vitro sensitivity to heparin and clearance rate from plasma in vivo). Moreover, neither of them could be correlated with the response to heparin, subsequently observed during ECC in the same patients. Preoperative investigations with the methods presently available are not adequate to choose individual heparin administration regimens for cardiac operations.

Heparin administration for operations with extracorporeal circulation (ECC) usually is performed following prefixed, standardized protocols. These regimens secure an adequate level of anticoagulation, but they often involve prolonged periods of overheparinization associated with an undue risk of hemorrhage. The predictive value of preoperative studies in the anticoagulant effect of heparin was investigated in 10 patients. The study was performed both in vitro and in vivo using the Xa inhibitor assay as an index of the anticoagulation induced by heparin. Adding variable amounts of heparin in vitro to patient's plasma resulted in straight (at least up to 7 U. per milliliter) and parallel, but not coincident, dose/response curves, so confirming a different individual sensitivity to heparin. Disappearance curves of the anticoagulant effect in plasma following intravenous administration of a single standard dose of heparin in the same patients showed an even greater patient-to-patient variability, with "half-life" times ranging from 30 to 150 minutes. No relationship was found between the parameters (in vitro sensitivity to heparin and clearance rate from plasma in vivo). Moreover, neither of them could be correlated with the response to heparin, subsequently observed during ECC in the same patients. Preoperative investigations with the methods presently available are not adequate to choose individual heparin administration regimens for cardiac operations.

Three substances widely used as vasoactive drugs are known to have an inhibiting effect on platelet aggregation ‘in vitro’. We investigated the changes induced on thrombelastogram, routine clotting tests, euglobulin lysis time (ELT), platelet count, aggregation, and adhesiveness by i, v. administration of these drugs to man. The same indices were also studied ‘in vitro’ by adding comparable concentrations of the substances to human blood or plasma.Aminophilline did not produce any significant variation in ADP-or collagen-induced aggregation either ‘in vitro’ (50 to 200 μg/ml) or ‘in vivo’ (240 mg). A trend to disaggregation was seen only in a few cases. Shorter ELT were found 30 and 120 minutes after injection.A papaverine derivative (Metaverinum, 150 mg) showed a similar ‘in vivo’ pattern: minor changes in platelet function tests and a moderate activation of fibrinolysis were seen. The drug acted ‘in vitro’ as a powerful inhibitor of aggregation (from 30 µg/ml)while fibrinolysis was only activated at the highest concentration (120 µg/ml).Bencyclan, capable of inhibiting platelet function ‘in vitro’ at very low concentrations (0.25µM) did not show similar effects ‘in vivo’ (50 mg) apart from a reduced platelet adhesiveness to glass.