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G Palareti

Publications and source records attributed to G Palareti.

At least 19 recordsLinked to original sources
PubMed1999

Screening for activated protein C resistance before oral contraceptive treatment: a pilot study.

The feasibility and cost-effectiveness of screening women for congenital thrombophilic alterations before oral contraceptive (OC) treatment was investigated. A total of 525 women (mean age 21.9 years, 73% aged < 25 years) were examined before their first OC course. At first screening, completely normal results were recorded in 485 (92.4%) women, the remaining showing single (n = 34) or multiple (n = 6) alterations. At second examination (possible in 37 of 40), activated protein C resistance (APCR) was confirmed in 21 cases (4.0%, 18 with factor V Leiden), protein C, or protein S reduction in 8 (1.5%) and 2 (0.4%) cases, respectively. No cases with antithrombin III deficiency were detected. The global estimated cost ($US) to detect one altered case was: $7795 for protein S, $2696 for antithrombin III (no case found), $1374 for protein C and $433 for APCR. The present study confirms that extensive thrombophilic screening before OC treatment is not currently advisable. APCR assessment, however, seems to have a favorable cost-effectiveness ratio: the alteration is frequent and has a synergistic effect with OC; sensibility and specificity of some methods are good; family history is unreliable to single out possible carriers; finally, carriers can be fully informed of their increased thrombotic risk if treated with OC and can receive thromboprophylaxis during life situations associated with high thrombotic risk (e.g., pregnancy and puerperium).

Activated Protein C Resistance↗
PubMed1999

Contribution of a new, rapid, quantitative and automated method for D-dimer measurement to exclude deep vein thrombosis in symptomatic outpatients.

Ninety-nine consecutive outpatients with symptoms suggestive of deep vein thrombosis (DVT) were tested for the presence of D-dimer using a new, rapid method (BC D-Dimer) based on the agglutination principle and performed on a BCT analyzer. Dimertest Gold EIA and VIDAS D-Dimer devices were used as comparative methods. Venography was performed in all patients, with DVT diagnosed in 39 of them (34 proximal). The BC D-Dimer test proved to be rapid, automated and well suited for individual tests with a good reproducibility (coefficient of variation % 1.5-5.3). Its performance was comparable with that of the other methods, as indicated by the areas under the receiver operating characteristic curves (Gold EIA 0.95; VIDAS 0.95; BC D-Dimer 0.91) and the coefficients of correlation (Pearson's coefficients from 0.832 to 0.876). On the basis of the Kappa coefficients, there was quite a good concordance between the three tests. At the cut-off levels that provided the highest sensitivity (97.4%, for all the tests), the negative predictive values were similar for all methods, at over 95%. The corresponding specificity ranged from 62.7 to 81.7%. In conclusion, this study shows that the new method can be included in prospective clinical trials to test the utility of D-dimer measurement in combination with other non-invasive diagnostic procedures in the management of the diagnosis of DVT.

Adult↗
PubMed1999

Risk of venous thromboembolism and clinical manifestations in carriers of antithrombin, protein C, protein S deficiency, or activated protein C resistance: a multicenter collaborative family study.

Deficiencies of antithrombin (AT), protein C (PC) or protein S (PS), and activated protein C resistance (APCR) are very well-established coagulation defects predisposing to venous thromboembolism (VTE). We performed a retrospective cohort family study to assess the risk for VTE in individuals with AT, PC, or PS deficiency, or APCR. Five hundred thirteen relatives from 9 Italian centers were selected from 233 families in which the proband had had at least 1 episode of VTE. We calculated the incidence of VTE in the whole cohort and in the subgroups after stratification by age, sex, and defect. The overall incidence of VTE (per 100 patient-years) in the group of relatives was 0.52. It was 1.07 for AT, 0.54 for PC, 0.50 for PS, 0.30 for APCR, and 0.67 in the group with a double defect. The incidence was associated with age, but not with sex. The mean age at onset was between 30 and 40 years for all the coagulation defects. Women had the peak of incidence in the age range of 21 to 40 years, earlier than men. The lifetime risk for VTE was 4.4 for AT versus APCR, 2.6 for AT versus PS, 2.2 for AT versus PC, 1.9 for PC versus APCR, and 1.6 for PS versus APCR. AT deficiency seems to have a higher risk for VTE than the other genetic defects. There is a relation between age and occurrence of thrombosis for both men and women. The latter had the peak of incidence earlier than the former.

Activated Protein C Resistance↗
PubMed1999

Antithrombin replacement in patients with sepsis and septic shock.

Sepsis is a frequent complication of critically ill patients and its incidence is increasing. Currently, septic shock is the most common cause of death in non-coronary intensive care units. Over the last 10 to 15 years, new antibiotics and increasingly sophisticated critical care have had little impact on the mortality rate of septic shock. The Italian SEPSIS Study, carried out in 99 intensive care units in 1994, reported mortality rates of 52% and 82% for severe sepsis and septic shock respectively. New therapeutic approaches aimed at neutralizing microbial toxins and modulating host mediators have shown some efficacy in large clinical trials and/or in animal models, but to date, no therapy of sepsis aimed at reversing the effects of bacterial toxins or of harmful endogenous mediators of inflammation has gained widespread clinical acceptance. Because of the strong association of severe sepsis with a state of activation of blood coagulation and of the potential role of capillary thrombosis in the development of the multiple organ dysfunction syndrome, anticoagulant agents have been tested in the setting of septic shock. However, neither administration of heparin nor of active site-blocked factor Xa or of anti-tissue factor antibodies have proven effective in preventing deaths due to septic shock in animal models. In contrast, infusion of antithrombin, protein C, or tissue factor pathway inhibitor all resulted in a significant survival advantage in animals receiving lethal doses of E. Coli. Antithrombin concentrates have been used in a significant number of critically ill patients. A double-blind, placebo controlled study carried out in 3 italian intensive care units has recently shown that the administration of antithrombin aimed to normalize plasma antithrombin activity had a net beneficial effect on 30-day survival of patients requiring respiratory and/or hemodynamic support because of severe sepsis and/or post-surgery complications.

Antithrombins↗
PubMed1998

Antithrombin III (ATIII) replacement therapy in patients with sepsis and/or postsurgical complications: a controlled double-blind, randomized, multicenter study.

BACKGROUND: ATIII is decreased in sepsis and/or shock and its baseline value correlates with mortality. The efficacy of ATIII therapy on mortality was assessed in a selected group of patients admitted to the intensive care unit (ICU) in a double-blind, randomized, multicenter study. METHODS: 120 patients admitted to the ICU with an ATIII concentration < 70% were randomized to receive ATIII (total dose 24000 units) or placebo treatment for 5 days; 56 patients had septic shock. RESULTS: ATIII concentrations in the treated group remained constant throughout the treatment period (range 97-102%). The Kaplan-Meier analysis showed no difference in overall survival between the two groups: 50 and 46% for ATIII and placebo, respectively. Septic shock and hemodynamic support were unbalanced in the two groups at admission. Therefore the Cox analysis was carried out after adjusting for these two variables. Treatment with ATIII decreases the risk of death with an odds ratio (OR) of 0.56. Of the covariates analyzed, septic shock and the baseline multiple organ failure score were negatively associated with survival and plasma activity level was positively associated with survival with an OR of 0.97 for each 1% increase in the ATIII plasma concentration at baseline. CONCLUSIONS: The results of ATIII treatment in this population of patients suggests that replacement therapy reduces mortality in the subgroup of septic shock patients only.

APACHE↗
PubMed1998

Systemically circulating oxidative species in human deep venous thrombosis.

To investigate the hypothesis that plasmatic changes of lipoperoxidative markers are associated with deep venous thrombosis (DVT), peripheral venous blood samples were obtained from 10 patients with venographically proven DVT before starting anticoagulant therapy, and 36+/-3 and 60+/-3 hours later. Values of myeloperoxidase (MPO), 4-hydroxynonenal (HNE) and malondialdehyde (MDA) were compared with those of 10 age-matched control subjects. Despite individual variations, mean plasma MPO level was higher in the DVT group (p < 0.01), as were average plasma MDA (p < 0.001) and HNE (p < 0.01) levels. Separate analysis of the DVT cases showed that higher values of MDA, HNE and MPO were found in patients with either co-morbid diseases or clinically silent pulmonary embolism (PE). Good evidence exists for considering DVT a condition associated with an apparently excessive free radical production not buffered by efficient defence systems. A role of DVT itself cannot be excluded, but PE or other co-morbid diseases may participate in the oxidative stress. If confirmed in a larger series of patients, these findings could shed new light on the plasmatic changes associated with the propagation and complications of DVT, which in turn could have therapeutic implications.

Adult↗
PubMed1997

Comparison of new rapid methods for D-dimer measurement to exclude deep vein thrombosis in symptomatic outpatients.

Eighty-seven outpatients consecutively admitted to the emergency unit of our hospital with clinically suspected first deep vein thrombosis (DVT) of a leg had D-dimer levels measured by the following recently introduced fast methods: VIDAS (bioMerieux), LPIA (Mitsubishi), Nephelotex (Biopool), Nycocard (Nycomed) and Instant.I.A. (Diagnostica Stago). A latex agglutination test (Minutex, Biopool) was also performed and a classical ELISA (Gold EIA, Agen) used as reference. Venography was performed in all patients, with DVT diagnosed in 42 (37 proximal). All the new methods can be adopted in emergency situations, since they are suited for individual tests, are rapid and the reagents ready to use. All the methods proved to have a good interassay reproducibility. The new D-dimer and latex agglutination tests showed negative (88-96%) and positive (63-81%) predictive values similar to those of ELISA (92% and 71%, respectively), though the still wide confidence intervals suggest larger patient population series be investigated. As regards clinical application, the use of these tests to rule out DVT should be tested in prospective clinical follow-up trials where anticoagulation is withheld in subjects with negative non-invasive reliable vascular tests and normal D-dimer levels.

Biological Assay↗
PubMed1997

The heterozygous 20210 G/A prothrombin genotype is associated with early venous thrombosis in inherited thrombophilias and is not increased in frequency in artery disease.

A genetic variation in the 3'-untranslated region of the prothrombin mRNA (20210 G/A) has recently been reported to be associated with elevated plasma prothrombin levels and with an increased incidence of venous thrombosis. We determined the frequency of this mutation, the detection of which was improved by allele-specific amplification of exon 14 and by denaturing gradients (denaturing gradient gel electrophoresis), in cohorts of patients affected by venous thrombosis (n = 132) or by coronary or cerebrovascular diseases (n = 195) and in normal subjects from various populations. An overlapping frequency of the heterozygous genotype (4%) was found in normal subjects from Italy and Cyprus, and no carrier was detected in 40 subjects of Indian or Somali origin. The 20210 GA heterozygous genotype was not increased in frequency in patients with arterial disease. In contrast, the GA genotype was associated (P = .007) with venous thrombosis both in simple heterozygotes (16%) with a family history of thrombosis as well as in double heterozygotes (14%) for other known thrombophilic defects. A synergic interaction between the prothrombin 20210 GA genotype and the factor V Leiden mutation, both potentially affecting the prothrombinase complex, was suggested by the early onset of thrombosis (median age 22 years) in doubly heterozygous patients. The association of the 20210 A allele with higher prothrombin levels was confirmed in the Italian population. However, the prothrombin assay does not allow an efficient preselection of patients for the DNA analysis.

Adolescent↗
PubMed1997

Hyperhomocyst(e)inemia and a common methylenetetrahydrofolate reductase mutation (Ala223Val MTHFR) in patients with inherited thrombophilic coagulation defects.

To assess whether certain abnormalities of the sulfated amino acid metabolism are associated with the occurrence of thromboembolic events in patients with inherited thrombophilic conditions, the levels of homocyst(e)ine, before or after methionine load, and the presence of the Ala223Val substitution in the 5,10-methylenetetrahydrofolate reductase (MTHFR) were evaluated in 119 subjects with a congenital single thrombophilic condition (type I deficiency of antithrombin n = 10, protein C n = 24, protein S n = 16; activated protein C resistance due to factor V Leiden mutation n = 69). Sixty-three subjects had experienced at least one documented thrombotic event, while the remaining 56 subjects were still free from any thrombotic symptom. Our results show that (1) high homocyst(e)ine levels, either in fasting condition or after methionine load, were not more frequent in subjects with inherited thrombophilic alterations (14.4%) than in normal control subjects (10% by definition) and (2) the frequency of hyperhomocyst(e)inemia was similar in thrombophilic subjects, who already have (14.3%) or have not (14.6%) experienced thrombotic events. As regards the MTHFR mutation, the homozygous condition was present in 23.2% of the thrombophilic patients versus 17.5% in the control subjects, a nonsignificant difference. The mutation was slightly more frequent in those thrombophilic subjects who had suffered a thrombotic episode (25.5%) versus those with no thrombosis (20.8%), with odds ratios of 1.61 (confidence interval (CI) = 0.58-4.52) and 1.24 (CI = 0.42-3.43), respectively. These differences were also nonsignificant. It is concluded that in subjects with inherited thrombophilias, a condition of hyperhomocyst(e)inemia "per se" is not a factor increasing the risk of thrombosis. The risk enhancement conferred by the MTHFR mutation, if any, seems to be slight or limited, and its significance could be ascertained only in a large multicenter trial.

Adult↗
PubMed1997

[Hemorrhagic complications of oral anticoagulant therapy: results of a prospective multicenter study ISCOAT (Italian Study on Complications of Oral Anticoagulant Therapy)].

BACKGROUND: To assess the incidence of bleeding complications during oral anticoagulant therapy (OAT) in a population of patients representative of daily practice in Italian anticoagulation clinics. METHODS DESIGN: prospective, inception-cohort, multicentre. SETTING: Thirty-four anticoagulation clinics federated in the Italian Federation of Anticoagulation Clinics. PATIENTS: 2745 consecutive patients, included from beginning of their first OAT course. Most patients were aged between 60 and 79 y (57.8%), with 8% being > or = 80 y. Venous thromboembolism was the most frequent indication for OAT (one third of all the patients), followed by non ischemic heart disease which mainly included atrial fibrillation (16.8% of patients). Warfarin (in 63.8% of patients) and acenocoumarol were the only anticoagulant drugs used. The targeted anticoagulation intensity was low (INR < or = 2.8) in 71% of patients and high (INR > 2.8) in the remainder. OUTCOMES: Fatal, major and minor bleeding events. Thrombotic events were also recorded, though not analyzed in the present report. FINDINGS: During the 2011 patient-years (pt-y) of follow-up, 153 bleeding complications (7.6% pt-y) were recorded--5 fatal (all cerebral haemorrhages, 0.25% pt-y), 23 major (1.1% pt-y) and 125 minor (6.2% pt-y). The rate of events did not vary according to sex, coumarin type, size of enrolling centre or targeted therapeutic range; it was higher in older patients (10.5% pt-y in those aged > or = 70 y, relative risk--RR--1.75, p < 0.001), in cases where indication for anti-coagulant treatment was peripheral and/or cerebrovascular disease (12.5% pt-y; RR 1.80, p < 0.01) and during the first 90 days of treatment (11% pt-y, RR 1.75, p < 0.001). One fifth of bleeding events occurred at a very low anticoagulation intensity (INR < 2; the category rate being 7.7% pt-y); the rate was 4.8% pt-y in the 2.0-2.9 INR category, reaching 9.5% pt-y, 40.5% pt-y and 200% pt-y in the 3-4.4, 4.5-6.9 and > or = 7 INR categories respectively (RR for INR levels > 4.5 = 7.91, p < 0.0001). CONCLUSIONS: The overall rate of bleeding events recorded in the present study was much lower than that recorded in other (including recent) observational and experimental studies. The risk of bleeding increased in the following cases: age > 70 y; arterial vascular disease as indication for OAT; first 3 months of treatment; INR values > or = 4.5. OAT has become safer in recent years, particularly if monitored in special anticoagulation clinics. Caution should be exercised when prescribing OAT in elderly patients and the intensity anticoagulation levels should be closely monitored to minimize incidental periods of overanticoagulation.

Aged↗
PubMed1997

Transfusion requirements are correlated with the degree of proteolysis of von Willebrand factor during orthotopic liver transplantation.

During orthotopic liver transplantation (OLT) excessive bleeding is the main cause of death and graft failure. The acute bleeding tendency that accompanies OLT, particularly during the anhepatic period and after reperfusion of the graft, is due to the depletion or functional abnormalities of several hemostasis components caused by the enhanced activity of enzymes such as plasmin, trypsin and leukocyte proteases. We surmised that enhanced proteolysis might also cause abnormalities of von Willebrand factor (vWF), and that these abnormalities are implicated in the bleeding tendency that develops during OLT. Therefore, the pattern of vWF proteolysis was studied with 16 patients with chronic liver disease, in serial blood samples obtained before OLT, during the anhepatic stage, after graft reperfusion and at the end of the surgical procedure. vWF became markedly degraded during the anhepatic and reperfusion stages, as shown by the partial loss of high molecular weight multimers, the relative decrease of the intact 225 kD subunit and the increase of the native proteolytic fragments of 176 and 140 kD. Novel proteolytic fragments also became detectable. Using monoclonal antibody epitope mapping, it could be demonstrated that some of the proteolytic fragments corresponded in apparent molecular mass to those produced in vitro by incubating purified vWF with plasmin or elastase, but other fragments could not be attributed to these proteases. During the anhepatic and reperfusion stages there was a significant correlation between the degree of vWF degradation and the total amount of blood components transfused to replace blood losses. To evaluate whether or not vWF degradation could be controlled by the administration of a broad-spectrum protease inhibitor such as aprotinin, 5 patients were given a bolus dose of 500,000 U before surgery followed by 100,000 U/h during surgery, 5 were given a 2,000,000 U bolus followed by 500,000 U/h, and no aprotinin was given to the remaining 6 patients. There were no differences in the patterns or degrees of vWF degradation between patients treated with aprotinin or not. In conclusion, there is a marked degradation of a key hemostasis protein during OLT. These alterations may be of clinical significance, because they are correlated with the transfusion requirements.

Adult↗
PubMed1997

Assessment of mental ability in elderly anticoagulated patients: its reduction is associated with a less satisfactory quality of treatment.

Mental capacity was assessed in 311 apparently self-sufficient patients (> or = 60 years of age, 170 men) under stabilised oral anticoagulant treatment (OAT) by administering the Hodkinson's Abbreviated Mental Test (AMT). The international normalized ratios (INR) recorded during the 3 months before and the 3 after the data of test administration were examined by the INR-Day software program. The percentage of time spent within, below or above the intended therapeutic range was calculated in patients who scored abnormally at AMT, and compared with matched controls with normal AMT results. Forty patients [12.9%; 28 women (19.8%) and 12 men (7.1%), P < 0.0011] had abnormal AMT results; the rate seemed to increase with age. Most of these patients (35, 75%) had only elementary education. Patients with abnormal AMT results spent more time outside the intended therapeutic ranges than 40 matched controls (20.9% of the observed time vs 13.7%, P < 0.0001; odds ratio 1.68, CI 1.53-1.84). Unsuspected reduction of mental ability or attention levels was found in a number of elderly patients receiving OAT; these patients presented longer periods of either under- or over-anticoagulation and were, therefore, exposed to a higher risk of thrombotic or bleeding complications. Anticoagulation clinics would be advised to assess mental abilities in elderly patients before starting OAT.

Aged↗
PubMed1997

Thrombotic events during oral anticoagulant treatment: results of the inception-cohort, prospective, collaborative ISCOAT study: ISCOAT study group (Italian Study on Complications of Oral Anticoagulant Therapy).

The paper reports on rate and type of thrombotic events occurring during the observational, prospective, inception-cohort, multicenter ISCOAT study. 2,745 unselected, daily practice patients, consecutively referring to 34 Italian anticoagulation clinics to monitor the oral anticoagulant treatment, were included in the study from beginning of their first anticoagulant course. During a total follow-up of 2,011 patient-years of treatment 70 thrombotic events (3.5 per 100 patient years) were recorded in 67 patients: 20 fatal (1%), 39 major (1.9%) and 11 minor (0.6%). 34/70 events occurred within the first 90 days of treatment (relative risk - at multivariate analysis - of < or =90 days vs. >90 = 20.6, C.I. 12.7-33.5; p <0.0001). The risk was higher in patients aged > or =70 y (1.62, C.I. 1.0-2.61; p <0.05), and when indication for anticoagulant treatment was peripheral/cerebral arterial disease (1.84, C.I. 1.01-3.36; p <0.05). The frequency of thrombotic events was 17.5% when international normalised ratio (INR) levels were < 1.5, decreasing to 2.3% for INRs within the 2-2.99 category (relative risk of INRs <2.0 vs. > or =2 = 1.88, C.I. 1.16-3.07; p <0.05). The recorded rate of thrombotic events was lower than that reported in the few available studies. A greater risk should be expected during the first 90 days of treatment, when anticoagulation levels are <2.0 INR, in patients > 70 years and in those with cerebrovascular/peripheral arterial disease.

Administration, Oral↗