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Congenital agenesis of the inferior vena cava (AIVC) is a rare vascular abnormality with a prevalence of 0.0005 to 1% in the general population. This condition is found in almost 5% of young patients (younger than 30 years) with proximal, typically bilateral, deep venous thrombosis (DVT) of the lower limbs, often in the absence of apparent risk factors. However, AIVC in young patients with DVT is probably underestimated because AIVC cannot be detected by the standard DVT diagnostic workup. Inherited thrombophilia has been reported in patients with AIVC-associated DVT, as an additional risk factor, but its role is poorly investigated. The best therapeutic strategy and the optimal duration of anticoagulant treatment of DVT in patients with AIVC are still unclear. Here, we describe 14 young patients (2 females and 12 males, mean age at first DVT: 27.8 ± 10.1 years), with color Doppler ultrasound (US) and abdominal computed tomography scan confirmed AIVC-associated DVT and discuss their characteristics in the framework of a literature review on this topic. Our patients were mainly males (10/12) and experienced proximal DVT events, not complicated by pulmonary embolism. DVT-precipitating factors were detected only in five cases, the two female patients (oral contraceptives and puerperium), and three male patients (one after leg fracture and two after abdominal surgery). Thrombophilic abnormalities were found in eight patients (heterozygous factor V Leiden mutation, n = 3; mild/moderate hyperhomocysteinemia, n = 3; reduced protein C activity, n = 1; antiphospholipid syndrome, n = 1). The majority of patients (13/14) were treated with long-term oral anticoagulant therapy and elastic stockings (ES), with a very low rate of DVT recurrence (1/14, mean follow-up 7 years). These clinical characteristics were largely consistent with those of 161 patients identified by review of the literature. On the whole, although many aspects are still poorly known, our case series and literature review suggest that a search should be undertaken for AIVC in young patients with proximal idiopathic, particularly when bilateral, DVT, which should then be treated with prolonged anticoagulation and ES.

Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a rare, life-threatening thrombotic microangiopathy caused by severe ADAMTS13 (a disintegrin and metalloproteinase with thrombospondin motifs 13) deficiency, recurring in 30&ndash, 50% of patients. The common human leukocyte antigen (HLA) variant rs6903608 was found to be associated with prevalent iTTP, but whether this variant is associated with disease relapse is unknown. To estimate the impact of rs6903608 on iTTP onset and relapse, we performed a case-control and cohort study in 161 Italian patients with a first iTTP episode between 2002 and 2018, and in 456 Italian controls. Variation in rs6903608 was strongly associated with iTTP onset (homozygotes odds ratio (OR) 4.68 (95% confidence interval (CI) 2.67 to 8.23), heterozygotes OR 1.64 (95%CI 0.95 to 2.83)), which occurred over three years earlier for each extra risk allele (&beta, &minus, 3.34, 95%CI &minus, 6.69 to 0.02). Of 153 survivors (median follow-up 4.9 years (95%CI 3.7 to 6.1)), 44 (29%) relapsed. The risk allele homozygotes had a 46% (95%CI 36 to 57%) absolute risk of relapse by year 6, which was significantly higher than both heterozygotes (22% (95%CI 16 to 29%)) and reference allele homozygotes (30% (95%CI 23 to 39%)). In conclusion, HLA variant rs6903608 is a risk factor for both iTTP onset and relapse. This newly identified biomarker may help with recognizing patients at high risk of relapse, who would benefit from close monitoring or intensified immunosuppressive therapy.

Antiphospholipid syndrome (APS) can be primary or secondary to other autoimmune disorders. Besides valvular heart disease (VHD) and coronary artery disease (CAD), little is known about the impact of APS on left ventricular (LV) function.After excluding CAD, relevant VHD and heart failure, 69 patients (mean age = 43.9 years, 40 with primary and 29 with secondary APS) were assessed by echo-Doppler. Sixty-nine heathy controls, matched for age and sex, formed the control group. APS was diagnosed in presence of at least one clinical criteria and one confirmed laboratory criteria, including lupus anticoagulant (LA) titre. The adjusted global APS score (aGAPSS), derived from the combination of risk factors for thrombosis and autoimmune-antibody profile was calculated.Patients had similar blood pressure and heart rate, but higher body mass index (BMI) than controls. LV mass index (p = 0.007) and left atrial volume index (p 0.01) were greater, while early diastolic velocity (e') was lower (p = 0.003) and E/e' higher (p = 0.007) in APS. Primary APS patients had lower E/A and e' compared to both controls and secondary APS, while E/e' was higher in secondary APS than in controls. APS patients with diastolic dysfunction were older but did not differ for risk factors prevalence from those with normal/indeterminate diastolic function. In the pooled APS, LA positivity was independently associated with e' and E/e' after adjusting for age, BMI and aGAPSS in separate multivariate models.In APS, LV diastolic abnormalities are detectable. They are more pronounced in primary APS and independently associated with LA positivity.

Background The efficacy of risk model scores to predict venous thromboembolism (VTE) in ambulatory cancer patients is under investigation, aiming to stratify on an individual risk basis the subset of the cancer population that could mostly benefit from primary thromboprophylaxis. Materials and Methods We prospectively assessed 843 patients with active cancers, collecting clinical and laboratory data. We screened all the patients with a duplex ultrasound (B-mode imaging and Doppler waveform analysis) of the upper and lower limbs to evaluate the right incidence of VTE (both asymptomatic and symptomatic). The efficacy of the existing Khorana risk model in preventing VTE was also explored in our population. Several risk factors associated with VTE were analyzed, leading to the construction of a risk model. The Fine and Gray model was used to account for death as a competing risk in the derivation of the new model. Results The risk factors significantly associated with VTE at univariate analysis and further confirmed in the multivariate analysis, after bootstrap validation, were the presence of metastatic disease, the compression of vascular/lymphatic structures by tumor, a history of previous VTE, and a Khorana score >2. Time-dependent receiving operating characteristic (ROC) curve analysis showed a significant improvement in the area under the curve of the new score over the Khorana model at 3 months (71.9% vs. 57.9%, p = .001), 6 months (75.4% vs. 58.6%, p Conclusion ONKOTEV score steps into history of cancer-related-VTE as a promising tool to drive the decision about primary prophylaxis in cancer outpatients. The validation represents the goal of the prospective ONKOTEV-2 study, endorsed and approved by the European Organization for Research and Treatment of Cancer Young Investigators Program.

Acquired hemophilia A (AHA) is a rare, but often severe, bleeding disorder caused by autoantibodies against clotting factor VIII (FVIII). AHA occurs more frequently in the elderly and in association with several conditions, such as malignancies, autoimmune diseases, postpartum, or drug exposure; however, about half of the cases remain idiopathic. At variance with congenital hemophilia, where hemarthroses are the most common bleeding symptoms, hemorrhages in AHA involving soft tissues (muscle, skin) are more frequently reported. AHA is diagnosed in patients: with negative personal or family bleeding history; in which prolonged activated partial thromboplastin time is not corrected after mixing and incubating equal volumes of patient and normal plasma for ~2 hours at 37°C; FVIII levels are reduced; and a specific FVIII-inhibiting activity is detected. Prompt recognition and treatment of AHA are mandatory, as inadequate management and complications of the disease are associated with high mortality rates. Therapeutic approaches should aim to control acute bleeds, eradicate FVIII-autoantibody production, treat associated diseases, and when possible, eliminate them. Present knowledge about this often overlooked and challenging condition has significantly increased following establishment of recent national and international studies, as will also be reviewed in this article.

The prompt and accurate diagnosis of pulmonary embolism (PE) greatly influences patient outcomes. However, diagnosing PE is one of the most difficult challenges confronting physicians, even more so when the clinical suspicion is addressed in children, during pregnancy, or in elderly patients. In these patient groups, symptoms and signs from concomitant conditions or diseases may mimic PE and make difficult defining clinical probability categories for PE as usually applied to general adult patients. Moreover, the diagnostic techniques show wider, specific limitations in these settings. PE is considered rare in children. The diagnostic management of a child with suspected PE is largely extrapolated from the knowledge achieved in adult patients. An increased risk of venous thromboembolism is reported in all trimesters of pregnancy and in the puerperium. An accurate diagnosis of PE in pregnancy has important implications, including the need for prolonged anticoagulation, delivery planning, and prophylaxis during future pregnancies, as well as concerns about future oral contraceptive use and estrogen therapy. Although incidence, morbidity, and mortality increase steadily with age, PE remains an underdiagnosed disease in elderly patients. About 40% of PE found at necropsy were not suspected antemortem. In the present article, challenges in diagnosing PE in children, during pregnancy, and in the elderly will be discussed, reviewing the available clinical, laboratory, and instrumental diagnostic strategies.

Background: Although patients with idiopathic VTE are at higher than normal risk of asymptomatic atherosclerosis and of cardiovascular events, the impact of cardiovascular risk factors on VTE is poorly understood. Objective: To assess the prevalence of the metabolic syndrome and of its components in patients with early-onset idiopathic VTE. Methods: As many as 323 patients referred to our Thrombosis Ward for a recent (< 6-months) early-onset idiopathic venous thromboembolism (VTE), were compared with 868 gender- and age-matched subjects, in whom a history of venous thrombosis had been excluded, referred during the same period time to our Ward. All had undergone a clinical assessment for smoking habits and for the presence of the components of the metabolic syndrome. Results: The metabolic syndrome was detected in 76/323 cases (23.5%) and in 81/868 controls (9.3%) (p < 0.001; OR:2.990; 95%C.I.:2.119-4.217). Smoking was more common in patients with idiopathic VTE than in controls. In addition to the metabolic syndrome as a whole, its major individual determinants (arterial hypertension, impaired fasting glucose plasma levels, abdominal obesity, hypertriglyceridemia, low HDL-cholesterol) significantly correlated with idiopathic VTE (p always < 0.05). The prevalence of thrombotic events was lower in females than in males (p = 0.000; OR:2.217), the latter being most often hypertensives, smokers, hypertriglyceridemics, carriers of a metabolic syndrome and of impaired fasting glucose than females. In a multivariate analysis, arterial hypertension, impaired fasting glucose, abdominal obesity, and hypercholesterolemia independently predicted idiopathic venous events. Conclusions: Both metabolic syndrome as a whole and its major components individually considered, independently predict early-onset idiopathic VTE.

Acquired hemophilia A (AHA) is a very rare disease, caused by the development of autoantibodies, directed against circulating factor VIII of coagulation. Age distribution is bimodal, with a first peak occurring among young women in the postpartum period, and a second major peak of incidence among elderly patients in whom it is frequently associated with malignancy and drugs. This disease often represents a life-threatening bleeding condition, especially in the elderly, thus requiring a prompt therapeutic intervention, including control of acute bleeding and eradication of the inhibitor by immunosuppressive therapy. The diagnosis of AHA should be considered in any elderly patient who presents with bleeding and prolonged activated Partial Thromboplastin Time. Moreover, the coexistence of a series of underlying diseases associated with AHA should be always searched for. An early recognition and an adequate treatment of this coagulation disorder and of the possible associated diseases play a significant role for a favourable outcome, but concomitant morbidities in the elderly may limit aggressive therapy and may complicate the clinical scenario. We report 3 consecutive elderly patients successfully treated with recombinant activated factor VII and standard immunosuppressive regimens, with remission of the disease.

Acquired hemophilia (AH) is a rare but severe bleeding diathesis characterized by autoantibodies against a clot- ting factor, in most cases Factor VIII (FVIII). This bleeding disorder occurs more frequently in the elderly and may be as- sociated with several conditions, such as malignancies, autoimmune diseases, postpartum or drugs; however, about half of cases remain idiopathic. At variance with congenital hemophilia, in which hemarthroses are the most common bleeding manifestations, in patients with AH hemorrhages involving soft tissues (muscle, skin) are more frequently reported. AH is diagnosed in patients without previous personal or family bleeding history in which prolonged activated partial throm- boplastin time is not corrected after mixing and incubating for 2-4 hours at 37°C equal volumes of patient and normal plasma, FVIII:C levels are reduced and a specific FVIII inhibiting activity is detected and measured by the Bethesda assay or its Nijmegen modification. A prompt recognition of this life-threatening bleeding disorder and an early and aggressive treatment are mandatory, as diagnostic delays or inadequate treatments are associated with high mortality rates (up to 44% in literature). Therapeutic approach of AH is devoted to stop acute bleeds and to eradicate the FVIII autoantibody. Bleed- ing episodes can be treated with FVIII concentrates or desmopressin in patients with low titer inhibitors, but FVIII bypass- ing agents (activated prothrombin complex concentrates and recombinant activated FVIIa) are required for those with high-titer inhibitors or more severe bleeds. Steroids alone or in combination with cyclophosphamide are effective for eradicating autoantibodies in most cases. More recently, increasing evidence suggests a role for rituximab in this setting, in particular as a second-line approach.

Coppola A, De Stefano V, Tufano A, Nardone G, Amoriello A, Cerbone AM, Di Minno G (Centro di Coordinamento Regionale per le Emocoagulopatie; Universita‘Federico II’, Napoli; A.O.R.N. ‘A. Cardarelli’, Napoli; Italy). Long-lasting intestinal bleeding in an old patient with multiple mucosal vascular abnormalities and Glanzmann's thrombasthenia 3-year pharmacological management (Case report). J Intern Med 2002; 252: 271–275. A 75-year-old woman with Glanzmann's thrombasthenia was admitted because of persistent melaena. Endoscopic examination showed multiple angiodysplastic lesions, with active bleeding in small and large bowel. Electro-coagulation of some lesions, octreotide, conjugated oestrogens and selective embolization of jejunal vessels did not change transfusion requirements. After 8 month-transfusions, ethinylestradiol + norethisterone in association with octreotide was started, leading to no transfusion over the following 9 months. Bleeding recurred after withdrawing octreotide and substituting ethinylestradiol + norgestrel for the ethinylestradiol + norethisterone combination. Re-introduction of octreotide did not improve bleeding; however, a reduction of transfusion requirement was observed when the ethinylestradiol + norethisterone pill was re-administered. The association of octreotide and of an oestrogen–progesterone combination was helpful in the difficult management of recurrent bleeding in this patient with diffuse gastrointestinal vascular abnormalities and a severe condition predisposing to bleeding.

To the Editor: The prevalence of some gene polymorphisms associated with inherited thrombophilia and its potential relevance in the ischemic stroke of young women was recently described in Stroke. 1 At variance with patients with ischemic stroke, an increased risk of cerebral vein thrombosis (CVT) has been associated with the G20210A prothrombin (PRTH) gene mutation and oral contraceptive drugs. This finding was consistent with those in previous studies.2 3 In another study, a higher-than-normal prevalence of factor V Leiden mutation among CVT patients was reported.4 According to previously described methods,5 we have screened these …

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare clonal stem cell disorder characterized by intravascular hemolytic anemia that results from the clonal expansion of hematopoietic stem cells harboring somatic mutations in an X-linked gene, termed PIG-A (phosphatidylinositol glycan class A). PIG-A mutations block glycosylphosphatidylinositol (GPI) anchor biosynthesis, resulting in a deficiency or absence of all GPI-anchored proteins on the cell surface. CD55 and CD59 are GPI-anchored complement regulatory proteins. Their absence on PNH red cells is responsible for the complement-mediated intravascular hemolysis, leading to the release of free hemoglobin, which contributes to many of the clinical manifestations of PNH including fatigue, pain, esophageal spasm and possibly serious thrombotic episodes [1]. Allogeneic hematopoietic stem cell transplantation is the only curative therapy for PNH. The complement inhibitor eculizumab, a humanized monoclonal antibody against C5, that inhibits terminal complement activation, recently approved in the US, has been shown to reduce hemolysis, decrease the erythrocyte transfusion requirements and the risk for thrombosis, and to improve quality of life of PNH patients [2, 3]. Major morbidity and mortality with PNH are often ascribed to the development of venous thromboembolism (VTE) [1–6], and several patients have recurrent thromboses [7]. VTE in PNH patients occur mostly at unusual sites. Data from a recent review report hepatic vein thrombosis, leading to Budd-Chiari syndrome (BCS), as the most frequent (40.7%) thrombotic complication, accounting for the majority of deaths [8], followed by cerebral vein and sinus thromboses, superior sagittal sinus being the most frequently involved site [8]. Inherited thrombophilia may increase the risk of serious thromboembolic events in PNH patients [9]. In patients experiencing VTE, early anti-thrombotic therapy (heparin, thrombolysis) aimed to limit the extension of thrombosis, or to dissolve formed thrombi, should improve the prognosis of this severe complication. PNH patients suffering from VTE should be treated with anticoagulant drugs indefinitely [1]. Thrombocytopenia often complicates PNH, and this issue must be addressed when an anticoagulation management plan is formulated [1]. Recurrent, life-threatening thrombosis merits consideration for bone marrow transplantation (BMT) [1]. Over the past few years significant advances in other therapeutic approaches, such as transjugular intrahepatic portosystemic shunt (TIPS), have contributed to the improvement of survival in this setting [8]. We report the case of a 29-year-old woman, R. D. The family history was negative for VTE and cardiovascular disease. She was a non-smoker. And had been slightly overweight since childhood. When she was 19 years old, an isolated moderate thrombocytopaenia (50,000/mmc) was detected although in the absence of bleeding. As idiopathic thrombocytopaenia was diagnosed, she was treated with long-term steroids, with an improvement in the platelet count (120,000/mmc). At the age of 27, while on oral contraceptives for 3 months, she experienced a sudden occurrence of headache and visual loss, followed by seizures and coma. A computed tomography (CT scan) showed multiple cerebral venous thromboses. Screenings A. Tufano (&) N. Macarone Palmieri E. Cimino A. M. Cerbone Regional Reference Centre for Coagulation Disorders, Department of Clinical and Experimental Medicine, Federico II University of Naples, Via S. Pansini, 5, 80131 Naples, Italy e-mail: atufano@unina.it F. Alfinito Division of Hematology, Federico II University of Naples, Via S. Pansini, 5, 80131 Naples, Italy 123 Intern Emerg Med (2009) 4:75–77 DOI 10.1007/s11739-008-0182-7for congenital (antithrombin, protein C, protein S, factor V Leiden, prothrombin G20210A mutation, C677T MTHFR variant) and acquired (Lupus anticoagulant, antiphospholipid antibodies) thrombophilic abnormalities were negative. At that time, according to the available clinical records, she did not receive anticoagulant drugs, and symptoms improved after diuretics and steroid administration. Two years later, when she was 29 years of age, the patient was admitted to our hospital for recurrent abdominal pain, fever and pancytopaenia (WBC 4,000/mmc; Hb 9 g/dl; platelets 61,000/mmc). Steroid treatment had been withdrawn some weeks before the admission. Laboratory testing confirmed anaemia (9.8 g/dl) and a low platelet count (60,000/mmc), and also showed an increased LDH (1605 IU/L) ALP (137 IU/L) and cGT (112 IU/L) levels and reduced haptoglobin. An abdominal CT scan showed hepatic and splenic enlargement with ascites and signs of hepatic outflow obstruction, consistent with a Budd-Chiari syndrome (Fig. 1). Lupus anticoagulant and antiphospholipid antibodies were still negative. Homocysteine levels were normal. Cytofluorimetric investigation of peripheral blood cell immunophenotype showed abnormalities of complement regulatory proteins, consistent with the diagnosis of PNH [10]: 80% of red blood cells were CD59 deficient, 90% of granulocytes lacked CD 68b and 95% of monocytes did not show CD14 on cell membrane. Almost all hemopoesis was clonal. Bone marrow aspirate showed dysplastic features. Because of the thrombocytopenia, and while the patient was under evaluation for BMT, treatment with oral anticoagulants was delayed, and therapy with full-dose enoxaparin (100 IU/Kg bid) was started. Progressive splenic enlargement and bone marrow failure resulted in further reduction of the platelet count over the following three months (30,000/mmc); therefore, heparin dosage was reduced to 100 IU/Kg/d in order to avoid hemorrhagic complications. Six months later she experienced recurrent abdominal pain and ascites, compatible with a recurrence of the Budd-Chiari syndrome, and fatal hepatic failure. Her severe clinical condition hampered surgical or radiologic therapeutic approaches. Another PNH patient with a history of cerebral venous thrombosis and Budd-Chiari syndrome is described in a case-report published in 2005 [11]. The authors present the case of a 26-year-old man with a previous diagnosis of apparently idiopathic cerebral vein thrombosis, who developed hepatic venous thrombosis, and who had laboratory tests suggestive of PNH 9 months later. This patient underwent a TIPS, but experienced 1 month later an episode of stent blockage treated with balloon dilatation and restenting. In conclusion, our case report highlights that PNH should be considered in patients with venous thrombosis at unusual sites, especially if associated with haemocromocytometric abnormalities. Antithrombotic treatment in this setting is mandatory, but a careful risk-to-benefit ratio evaluation should be taken into account. A TIPS procedure may be a useful therapeutic option for PNH patients with Budd-Chiari syndrome, but caution is needed to prevent stent occlusion.

The assessment and monitoring of liver fibrosis (LF) is a key issue in the management and definition of prognosis of patients with chronic hepatitis C (CHC). In this respect, despite recognized limitations (invasive nature, sampling errors, interobserver variability, nondynamic evaluation of LF), liver biopsy is traditionally considered the reference standard. These limitations stimulated the search for noninvasive approaches for the assessment of LF, particularly attractive in patients with hemophilia and other congenital bleeding disorders (CBD). In patients with congenital bleeding disorders (CBD), who often suffer from CHC because of the past use of nonvirally inactivated plasma-derived products, the risk of bleeding hamper to routinely obtain histological data for LF staging. A variety of methods have been proposed and, in some cases, validated in patients with CHC and other liver diseases, including biomarkers directly or indirectly associated with LF, often combined in scores or algorithms, and the more recently developed physical approaches, evaluating the properties of the liver parenchyma with instrumental techniques studying the propagation of specific signals, that is, transient elastography (TE), acoustic radiation force impulse imaging elastography, and magnetic resonance elastography. This review will describe the available strategies for noninvasive assessment of LF, with more details on the latter promising instrumental approaches. Moreover, although lacking of validation against liver biopsy, recent studies extending the use of noninvasive methods (particularly TE) in the setting of patients with CBD will be discussed.

The prevalence of thrombophilic abnormalities in patients with cerebral vein thrombosis has been reported to be similar to that in patients with deep vein thrombosis of the lower limb. The role of gender-specific risk factors (pregnancy, oral contraceptives) is well established, whereas that of other acquired risk conditions is debated.We screened 56 patients with cerebral vein thrombosis and 184 age- and sex-matched apparently healthy controls for prothrombin (factor II, FII) G20210A and factor V Leiden polymorphisms; protein S, protein C, and antithrombin deficiency; anticardiolipin antibodies; hyperhomocysteinaemia and other putative risk factors.The G20210A polymorphism was found in 29.1% of patients and in 5.7% of controls (odds ratio [OR] 7.1; P0.0001; adjusted OR 12.67, P0.0001). Frequencies of factor V Leiden and hyperhomocysteinaemia were not significantly different in patients and controls, nor were the other thrombophilic tests and some established cardiovascular risk factors, such as smoking, obesity or overweight and arterial hypertension. Conversely, 53.7% of the women who developed cerebral vein thrombosis did so while assuming oral contraceptives (OR 6.12; P0.0001), with a further increase of risk in FII G20210A carriers (OR 48.533). Some associated diseases (onco-haematological disorders and infections) also had a significant role. Over a median 7-year follow-up, irrespective of the duration of antithrombotic treatment, 9/56 (16%) patients had further episodes of venous/arterial thrombosis. No significant risk factor for recurrent thrombosis was identified.In spite of the limitations of the sample size, our data confirm the role of FII G20210A mutation in this setting and its interactions with acquired risk factors such as oral contraceptives, also highlighting the risk of recurrent thrombosis in cerebral vein thrombosis patients.

SummaryWe sequenced the SERPINC1 gene in 26 patients (11 males) with antithrombin (AT) deficiency (22 type I, 4 type II), belonging to 18 unrelated families from Southern Italy. Heterozygous mutations were identified in 15/18 (83.3%) families. Of them, eight were novel mutations, each being identified in one family. Seven clearly cause impaired protein synthesis (four frameshift, one non-stop, one splicing and one 21bp deletion). One, present in a single patient, is a missense mutation thought to be causative because: a) it is absent in 100 chromosomes from controls; b) it involves a highly conserved amino acid, whose change is predicted to impair AT activity; c) no other mutation is present in the propositus. Severe mutations (i.e. nonsense, frameshift, deletions) were invariably identified in type I patients. In type II patients, 3/4 were missense mutations; the fourth leads to a 19 nucleotides shift in the stop codon. In addition to the type of mutation, the co-existence of other predisposing factors in most patients helps explain the severity of the present type I cases (age at first event, recurrence during prophylaxis). In the five families in which there was more than one member affected, the same genotype and a concordant clinical expression of the disease were found. We conclude that the molecular bases of AT deficiency in Southern Italy are different as compared to other geographic areas, and that molecular analysis and the study of the effect of the mutation may help predict the clinical expression of the disease.

Pathogenesis of atherosclerosis involves multiple mechanisms, including imbalanced lipid metabolism, disturbed equilibrium of the immune response, and chronic inflammation of the artery wall. Several reports have shown a relationship between the development of atherosclerosis and the presence of infectious diseases, widely occurring in the general population, often chronic and/or asymptomatic. Beyond Chlamydia pneumoniae, a large number of infectious agents have been linked with an increased risk of vascular disease, with variable strength of supporting data: Porphyromonas gingivalis, Helicobacter pylori, influenza A virus, herpes virus, hepatitis C virus, cytomegalovirus, and human immunodeficiency virus. Infections may contribute to atherosclerosis either via direct infection of vascular cells or via the indirect effects of cytokines or acute phase proteins induced by infection at " nonvascularo" sites. More recently, investigators reported that the aggregate burden ("infectious burdeno") of these chronic infections, rather than the effects of a single organism, might contribute to atherosclerosis and its thrombotic complications. However, the role of infection, as a proinflammatory cause of atherosclerosis, is still debated in the literature. This article will review available data suggesting a relationship between different infective pathogens and atherothrombosis, the hypothesized mechanisms, and the potential role for antimicrobial treatment.

Current guidelines for venous thromboembolism (VTE) primary prophylaxis are based on randomized clinical trials that exclude subjects at a potentially high bleeding risk. Thus no specific recommendation/algorithm for pharmacological prophylaxis in patients with thrombocytopenia and/or platelet dysfunction is available. Because at least 25% of subjects admitted to medical departments exhibit these conditions, information on this subject is provided here to optimize their VTE prophylaxis. Low platelet number/function and clotting abnormalities are common in patients with liver cirrhosis. However, these patients have a high incidence of portal and idiopathic venous thromboses, implying that cirrhotic coagulopathy does not protect against thrombosis. At variance with severe thrombocytopenia (50,000/mu L) should not interfere with VTE prevention decisions. In severe thrombocytopenia, prophylaxis should be considered on an individual basis, however. In patients with antiphospholipid antibodies and thrombocytopenia, a thrombotic tendency is usually associated rather than a bleeding risk. VTE prophylaxis in high-risk conditions is thus suggested in these patients. Except in cases with contraindications to anticoagulation, antithrombotic prophylaxis should be always considered in hospitalized cancer patients with thrombocytopenia, especially in those with hematologic malignancies and multiple VTE risk factors. Aspirin treatment is not as effective as heparins in lowering the risk of VTE. Studies in stroke suggest that thromboprophylaxis with heparins is safe in patients with ischemic stroke undergoing aspirin treatment. The need for VTE prophylaxis in patients on chronic treatment with aspirin and/or clopidogrel should be evaluated after assessing the individual risk-benefit ratio.

The use of antithrombotic drugs for the prevention of venous thromboembolism (VTE) in patients undergoing surgery is presently based on solid principles and high-level scientific evidence. This article reviews current strategies of pharmacological thromboprophylaxis. The level of VTE risk following surgery depends on a variety of factors that the surgeon should take into account, including the type of surgery and the presence of additional risk factors, such as elderly age and cancer. In patients undergoing minor general surgery, early mobilization is sufficient as prophylaxis, whereas in those undergoing major general surgery, thromboprophylaxis with low molecular weight heparin (LMWH), low-dose unfractionated heparin, or the pentasaccharide fondaparinux is recommended. Patients undergoing major orthopedic surgery have a particularly high risk of VTE, and routine thromboprophylaxis with LMWH, fondaparinux, or a vitamin K antagonist (international normalized ratio target: 2.0 to 3.0) is the standard of care in this group of patients. Recently, two new oral anticoagulants, rivaroxaban (a factor Xa inhibitor) and dabigatran etexilate (a direct thrombin inhibitor) have been licensed to be used for thromboprophylaxis after orthopedic surgery in Europe. Mechanical methods of thromboprophylaxis (compression stockings, intermittent pneumatic compression, vena cava filters), not discussed in detail in this review, should always be considered in patients at high thrombotic risk, in association with the pharmacological strategies, or in cases of contraindications to anticoagulants, as in patients or procedures at high risk of bleeding.

Diabetes mellitus (DM) is associated with macrovascular and microvascular complications. Platelets have a “key role” in atherogenesis and its thrombotic complications in subjects with DM. Moreover, the concomitant presence of multiple “classical” cardiovascular risk factors in diabetic subjects contributes to enhanced atherothrombotic risk. Antiplatelet agents are effective in primary and secondary prevention of arterial thrombosis (cardiovascular events, ischaemic stroke, and peripheral arterial occlusive disease). The role of chronic administration of antiplatelet drugs in primary prevention of arterial vascular events is known to be less clear than in secondary prevention, and, also in diabetic patients, the decision to give primary prophylaxis should be taken on an individual-patient basis, after a careful evaluation of the balance between the expected benefits and the risk of major bleedings. Although, currently, treatment has proven useful in reducing vascular events, diabetic patients continue to have a higher risk of adverse cardiovascular events compared with those in nondiabetic patients. This paper reviews the role of currently available antiplatelet drugs in primary and secondary prevention of vascular events in diabetic patients and the limitations of these drugs, and it discusses the role of novel and more potent antiplatelets and of new agents currently under clinical development.

A 47-year-old male, treated 7 years earlier for Hodgkin’s disease (HD), was admitted with persistent fever, liver enlargement, and increased cholestasis parameters. He developed acute bone marrow failure and progressive worsening of his clinical condition and cholestasis markers without showing evidence of HD recurrence or second malignancy. High-dose intravenous pulse methylprednisolone therapy was given, after which resolution of pyrexia and progressive improvement in performance status and in hematological counts and cholestasis parameters were observed. During this phase, a bone biopsy showed HD marrow infiltration. This clinical course may reflect tumor cytokine-induced phenomena, significantly affected by high-dose steroids.

Antiphospholipid antibodies are a heterogeneous group of auto-antibodies against phospholipids-binding proteins. The antiphospholipid syndrome is an autoimmune disorder characterized by the clinical association of antiphospholipid antibodies with a condition of hypercoagulability that can affect any blood vessel. Involvement of larger vessels, such as arteries or veins, manifests in the form of thrombosis or thromboembolism, whereas involvement of small vessels manifests as thrombotic micro-angiopathy. The antiphospholipid syndrome is also characterized by the presence of recurrent fetal loss. Patients who are persistently positive for antiphospholipid tests, and who have an arterial thrombosis or venous thrombosis history, are at increased risk of recurrence. Oral anticoagulant therapy is the mainstay of treatment for the thrombotic manifestations of the syndrome. Therapy with anticoagulant drugs should be long-term. On the other hand, although the thromboembolic potential of antiphospholipid antibodies has been well documented, there is still no general consensus on the prophylactic treatment of antiphospholipid antibodies carriers who have never developed vascular/obstetric manifestations. The effect of primary prophylaxis in antiphospholipid antibodies positive individuals is not well known and no evidence-based recommendations exist for thrombosis prevention in these individuals. However, the presence of risk factors for thrombosis increases the risk of first event of antiphospholipid antibodies positive patients. In conclusion, there is still much to learn on primary prophylaxis of asymptomatic antiphospholipid antibodies carriers. Hopefully, evidence-based guidelines will be available in the future.

Vascular glycosaminoglycans (GAG) are essential components of the endothelium and vessel wall and have been shown to be involved in several biologic functions. Mesoglycan, a natural GAG preparation, is a polysaccharide complex rich in sulphur radicals with strong negative electric charge. It is extracted from porcine intestinal mucosa and is composed of heparan sulfate, dermatan sulfate, electrophoretically slow-moving heparin, and variable and minimal quantities of chondroitin sulfate. Data on antithrombotic and profibrinolytic activities of the drug show that mesoglycan, although not indicated in the treatment of acute arterial or venous thrombosis because of the low antithrombotic effect, may be useful in the management of vascular diseases, when combined with antithrombotics in the case of disease of cerebral vasculature, and with antithrombotics and vasodilator drugs in the case of chronic peripheral arterial disease. The protective effect of mesoglycan in patients with venous thrombosis and the absence of side effects, support the use of GAG in patients with chronic venous insufficiency and persistent venous ulcers, in association with compression therapy (zinc bandages, multiple layer bandages, etc.), elastic compression stockings, and local care, and in the prevention of recurrences in patients with previous DVT following the standard course of oral anticoagulation treatment.

Injected factor VIII (FVIII), the current treatment for haemophilia A, leads to major improvements in the quality of life and life expectancy of individuals with this disorder. However, because injected FVIII has a short half-life in vivo, this strategy has major limitations for highly demanding regimens (e.g. prophylaxis, immune tolerance induction, surgery). Newer formulations of longer-acting FVIII are presently under investigation. The use of low molecular weight polyethylene glycol (PEG)-containing liposomes as carriers for recombinant FVIII (rFVIII) results in the prolongation of haemostatic efficacy. Data from preclinical experiments in mice, early clinical evaluations, and pharmacokinetics and pharmacodynamics results indicate that an rFVIII pegylated liposomal formulation may provide potential clinical benefit to patients with severe haemophilia A by prolonging the protection from bleeding. In light of this potential clinical benefit, a multicentre, randomized, active-controlled, non-inferiority phase II trial with two parallel treatment arms and equal randomization after stratification for the presence or absence of target joints in patients and for ages >/=18 years vs.

In Western countries, the treatment of patients with inhibitors is presently the most challenging and serious issue in haemophilia management, direct costs of clotting factor concentrates accounting for >98% of the highest economic burden absorbed for the healthcare of patients in this setting. Being designed to address questions of resource allocation and effectiveness, decision models are the golden standard to reliably assess the overall economic implications of haemophilia with inhibitors in terms of mortality, bleeding-related morbidity, and severity of arthropathy. However, presently, most data analyses stem from retrospective short-term evaluations, that only allow for the analysis of direct health costs. In the setting of chronic diseases, the cost-utility analysis, that takes into account the beneficial effects of a given treatment/healthcare intervention in terms of health-related quality of life, is likely to be the most appropriate approach. To calculate net benefits, the quality adjusted life year, that significantly reflects such health gain, has to be compared with specific economic impacts. Differences in data sources, in medical practice and/or in healthcare systems and costs, imply that most current pharmacoeconomic analyses are confined to a narrow healthcare payer perspective. Long-term/lifetime prospective or observational studies, devoted to a careful definition of when to start a treatment; of regimens (dose and type of product) to employ, and of inhibitor population (children/adults, low-responding/high responding inhibitors) to study, are thus urgently needed to allow for newer insights, based on reliable data sources into resource allocation, effectiveness and cost-utility analysis in the treatment of haemophiliacs with inhibitors.

The pathogenesis and treatment of retinal vein occlusions (RVO) are largely unclear. Prevalence of cardiovascular risk factors and of thrombophilic abnormalities was evaluated in 117 patients (61 M, 56 F; mean age 51 ± 13 years) with a history of RVO (62 central, CRVO; 48 branch, BRVO; 7 both) and in 202 age- and sex-matched control subjects. Cardiovascular outcome after a mean 8.2 year follow-up was recorded for 90 patients. Arterial hypertension was significantly more frequent in patients than in controls (64.9 vs. 28.2%; adjusted OR 4.5 95% CI 2.4–7.9; P < 0.0001), as well diabetes mellitus (17.9 vs. 7.9%; P < 0.05). Antithrombin, Protein C, Protein S and homocysteine levels, lupus anticoagulant, anticardiolipin antibodies, FV G1691A and prothrombin G20210A polymorphisms were comparable in the two groups, nor were different according to RVO localization or to the age at event. BRVO patients were significantly older (55 ± 9 vs. 47 ± 15 years; P = 0.002) and had higher prevalence of diabetes, overweight and hypertension (29.2 vs. 8.1%; 83.3 vs. 58.1%, 79.2 vs. 56.5%; P always

Inherited thrombophilia, defined as a genetically determined tendency to develop venous thromboembolism (VTE), contributes to the pathogenesis of approximately 40% of VTE episodes. About 50% of carriers of inherited thrombophilic traits develop VTE, but the impact of the different abnormalities is variable in terms of clinical penetrance. Some rare abnormalities (natural anticoagulant deficiencies, homozygous factor V Leiden, and combined defects) result in more severe thrombophilic phenotypes, characterized by early-onset events, more frequent recurrence, and positive family history, whereas the common polymorphisms (heterozygous factor V Leiden and prothrombin G20210A) are associated with lower VTE risk, often in association with triggering risk factors. Therefore, clinical implications of inherited thrombophilia should be assessed in the framework of coexisting and/or circumstantial risk factors involved in the multifactorial pathogenesis of VTE. These considerations should be taken into account when assessing the need and modalities of primary and secondary thromboprophylaxis in patients carrying inherited thrombophilic traits.

Diabetes mellitus is commonly associated with both microvascular and macrovascular complications (coronary artery disease, cerebrovascular events, severe peripheral vascular disease, nephropathy and retinopathy). There is wide evidence demonstrating that platelet degranulation and synthesis of TxA2 are increased in diabetic patients. For this reason, many studies on anti-platelet therapy have been made to reduce thrombotic complication of diabetes mellitus. Some diabetic patients, although treated with ASA, have a high prevalence of recurrent thrombotic events, which may presumably be due to an "ASA resistance". Nevertheless, this drug remains the one with the greatest benefit. To optimize its function, we should try to understand the causes of "aspirin resistance", try to find the most suitable dosage, recommending patients to comply constantly with the prescription given and to avoid interactions with other drugs. "Clopidogrel resistance" is a term not clearly defined. The clinical implications of "clopidogrel resistance" are unknown. An important consideration affecting the use of aspirin in diabetic patients is its interaction with ACE-inhibitors. Another question is antiplatelet therapy in nephropathic diabetic patients. Although these patients are at high thrombotic and haemorrhagic risk, they should nevertheless be considered eligible to undergo antithrombotic therapy, taking into account the individual's haemorrhagic risk.

To the Editor: Case-control1 2 and prospective3 4 studies have suggested an association between moderate hyperhomocysteinemia and risk of ischemic stroke. Homozygosity for the C-to-T substitution at nucleotide 677 of the gene of 5,10-methylenetetrahydrofolate reductase (MTHFR) is associated with a 50% reduction of the activity of this enzyme5 and is the most common inherited cause of moderate hyperhomocysteinemia. In 1996 Klujitmans et al6 reported a threefold increase in the risk of early-onset cardiovascular disease in homozygotes for the C677T MTHFR mutation. However, the association of this genetic marker with arterial vascular events has been disputed by a nested case-control study.7 Markus et al8 recently failed to show an association between cerebrovascular disease and the MTHFR genotype, a comparable prevalence of homozygosity for the C677T MTHFR mutation being detectable in a population of 345 patients with ischemic stroke or transient ischemic attacks (TIA) and in 161 control subjects (10.7% versus 13.7%, respectively). Nor were nonfasting log homocysteine plasma levels able to identify subjects with a stroke history in that setting, as judged by the analysis of a subgroup of patients (n=160) and control subjects (n=75) in whom this amino acid was measured. However, as expected, the authors found a significant relationship between MTHFR genotype and homocysteine levels, the latter being also independently related to log serum folate. In the frame of a larger study on juvenile thrombotic events, we have evaluated a population of 60 consecutive patients with a history of early-onset ischemic stroke (29 females and 31 males, aged 5 to 64 years [mean age, 38; mean age at time of diagnosis, 34; range 4 to 49 years]) documented within 72 to 96 hours from the event by CT and/or MRI scans. Subjects who had suffered from TIA or who exhibited abnormalities of carotid …

Summary. Prophylaxis with von Willebrand factor (VWF)-containing concentrates is considered to be a potential approach for patients with von Willebrand disease (VWD) and severe bleeding tendency. We report the case of a 57-year-old man with type 3 VWD and a history of recurrent melaena. Bleeding frequency and severity had progressively increased and the patient showed chronic anaemia and persistent haemoglobin in the stools. Endoscopic examinations revealed multiple vascular mucosal abnormalities (MVA) of the stomach and large bowel. Photocoagulation of some actively bleeding lesions and octreotide did not significantly affect his clinical conditions: six red cell transfusions and >400 000 IU of intermediate-purity factor VIII (FVIII) concentrate (Haemate P) on-demand were needed during 2002. Prophylaxis with Haemate P 40 IU kg−1 (102 IU kg−1 VWF:RCo) thrice weekly was associated with improvement of his mean haemoglobin levels, cessation of clear-cut melaena and red cell transfusions and reduction of total Haemate P requirements (−20% over 2003–04). Prophylaxis with Haemate P is still ongoing without any adverse event over a 30-month period. Clinical course and pharmacokinetic evaluations led to administer Haemate P each 72–96 h. Possible vascular complications were excluded by a careful clinical follow up, as the patient suffered from arterial hypertension and diabetes mellitus; thrombophilic abnormalities were previously excluded and no signs of abnormal coagulation activation or FVIII:C levels >150% were detected thereafter. Long-term prophylaxis with Haemate P has been shown to be safe, effective (also in terms of quality of life) and cost saving in this patient with severe gastrointestinal bleeding due to MVA and VWD.

Urothelial carcinomas are the fourth most common tumors. They can be divided in carcinomas of the lower urinary tract, if located in the bladder or urethra, or upper urinary tract carcinomas if located in the pyelocaliceal cavities and ureter. Bladder tumors represent the most common malignancy of the urinary tract, and account for the 90–95 % of urothelial carcinomas. On the other hand, upper tract urothelial carcinomas are uncommon, and account only for 5–10 % of urothelial tumors [1, 2]. We report a case of a 63-year-old woman referred to our department in February 2011 for a fever of unknown origin (FUO). She had suffered 30 months prior from mammary ductal carcinoma (staged pT1bN0), treated with quadrantectomy and tamoxifen, switched to exemestane after 2 years (of therapy); moreover, she was affected from HCV-related chronic hepatitis (viraemia: 1.22 9 10 IU/ mL, genotype 1b; naive) discovered in 1997. She complained of fevers up to 39 C mostly ‘‘nocturnal’’ sometimes accompanied by diarrhea, malaise, loss of appetite, weight loss and profuse sweating begun 4 months before. The patient was previously admitted in a different department of internal medicine for the same clinical status. During the hospitalization an abdomen computed tomography (CT scan) was performed that revealed only a reduced enhancement of contrast media in the upper pole of the left kidney. The patient was therefore discharged with a diagnosis of ‘‘fever in remission and renal ischemia’’. 1 month later, the temperature was still elevated, and the patient was admitted to our department. The physical examination revealed an emaciated facies, a body temperature of 37.8 C, a blood pressure of 160/80 mm Hg, and a murmur 2/6 Levine of the mitral valve; the remainder of the physical examination was normal. A complete blood count (CBC) showed a neutrophil leucocytosis (WBC: 11,200/mm, Ne 79.3 %) and a microcytic hypochromic anemia (related to a b-thalassemia trait). Other laboratory tests: GOT, GPT and c-GT were mildly elevated (1.25 ULN), C-reactive protein (CRP) was 1.77 mg/dL (normal value \0.5 mg/dL); electrolytes, erythrocyte sedimentation rate (ESR), blood culture, chest X-ray and urine culture were negative. At echocardiography, performed to exclude a subacute infective endocarditis, the patient presented only a mild mitral regurgitation with left atrial enlargement; there was no sign of valvular vegetations. At urine analysis the patient presented acid-sterile pyuria. Since the most common cause of sterile pyuria is renal tuberculosis, we proceeded with PPD skin test and Koch bacillus research in the urine; both were negative. As the patient was still febrile, an abdomen-CT scan with contrast media infusion was repeated, and revealed again an impairment of perfusion of the left kidney upper pole (reported as renal ischemia), but this time revealed also many lymphoadenopathies near the left renal vein and in the para-aortic region; the biggest one was 1.3 cm in the lumbar para-aortic region. Therefore, we decided to proceed with a total body F-fluorodeoxyglucose (FDG) positron emission tomography combined with computed tomography (PET/CT) to better evaluate the abdominal lymphoadenopathies, and to indentify a possible focus responsible of the fever. The only site with high FDG uptake was the lymph node in the lumbar region (max-standardized uptake value 8.7). About 20 days after admission the patient still presented M. Di Capua (&) P. Ierano E. Marrone A. M. Cerbone G. Di Minno Department of Clinical and Experimental Medicine, Regional Reference Centre for Coagulation Disorders, Federico II University of Naples, Via S. Pansini, 5, 80131 Naples, Italy e-mail: mirdica@hotmail.com

Background and Purpose — The mechanisms of ischemic stroke in young adults are poorly understood. During the last years, several studies suggested a role for genetic factors predisposing to thrombophilia and for moderate hyperhomocysteinemia in this setting. Methods — We evaluated in 132 consecutive patients (66 males, 66 females; mean±SD age, 38.4±11.7 years; mean±SD age at first event, 34.8±10.9 years; range, 6 months to 50 years) referred to our center between January 1997 and December 1999 for a history of young adult ischemic stroke (age at first event, Results — Total homocysteine levels differed significantly ( P =0.004, t test) between patients and controls: 13.03±18.61 versus 10.75±6.24 μmol/L (mean±SD), respectively. In contrast, homozygosity for the TT mutation of the MTHFR gene was 30 of 132 (22.7%) in patients and 45 of 262 (17.2%) in controls; this difference was not statistically significant ( P >0.05, χ 2 test). However, when we stratified the whole population according to genotype, fasting serum homocysteine levels were significantly higher in TT patients than in TT controls (25.3±36.8 versus 15±11.6 μmol/L; P =0.02, t test). Mutations of FV Leiden and of FII G20210A gene are currently reported to be associated with a tendency toward ischemic stroke. Their frequencies were not statistically significantly different between patients and controls in this setting: 7 of 132 (5.3%) versus 17 of 262 (6.5%) for FV Leiden and 10 of 132 (7.6%) versus 16 of 262 (6.1%) for FII G20210A, respectively (all P >0.05, χ 2 test). Conclusions — In the present cohort of patients, moderate hyperhomocysteinemia is the only variable that helps to identify young adults with a history of ischemic stroke.

Background — Severe hyperhomocysteinemia due to cystathionine β-synthase deficiency (CβSD) is associated with early atherothrombotic vascular disease. Homocysteine may exert its effects by promoting oxidative damage. In the present study, we investigated whether in vivo formation of 8-iso-prostaglandin (PG) F 2α , a platelet-active product of arachidonic acid peroxidation, is enhanced in CβSD and whether it correlates with in vivo platelet activation, as reflected by thromboxane (TX) metabolite excretion. Methods and Results — Urine and blood samples were obtained from patients with homozygous CβSD (n=13) and age-matched healthy subjects. Urinary 8-iso-PGF 2α excretion was significantly higher in CβSD patients than in control subjects (640±384 versus 213±43 pg/mg creatinine; P =0.0015) and correlated with plasma homocysteine (ρ=0.398, P =0.0076). Similarly, urinary 11-dehydro-TXB 2 excretion was enhanced in CβSD (1166±415 versus 324±72 pg/mg creatinine; P =0.0015) and correlated with urinary 8-iso-PGF 2α (ρ=0.362, P =0.0153). Vitamin E supplementation (600 mg/d for 2 weeks) was associated with a statistically significant increase in its plasma levels (from 16.6±4.6 to 40.4±8.7 μmol/L, P =0.0002) and with reductions in 8-iso-PGF 2α (from 790±159 to 559±111 pg/mg creatinine, P =0.018) and 11-dehydro-TXB 2 (from 1273±383 to 913±336 pg/mg creatinine, P =0.028). A statistically significant inverse correlation was found between urinary 8-iso-PGF 2α and plasma vitamin E levels (ρ=−0.745, P =0.0135). Conclusions — The results of the present study suggest that enhanced peroxidation of arachidonic acid to form bioactive F 2 -isoprostanes may represent an important mechanism linking hyperhomocysteinemia and platelet activation in CβSD patients. Moreover, they provide a rationale for dose-finding studies of vitamin E supplementation in this setting.

Under this scenario, it is poss-ible to discriminate between subjects with LVMappropriate to compensate an abnormal cardiacworkload at a given individual body size and gen-der, and those with LVM exceeding the value thatwould be normal for their loading conditions. Wetermed the latter condition ‘inappropriate LVM’. Inprevious reports we found that inappropriate LVMwas associated with relevant cardiovascular abnor-malities, suggesting that inappropriate LVM is ahigh-risk cardiac phenotype.

SummaryTotal fasting plasma homocysteine (tHcy), homozygosity for the C677T mutation of the methylenetetrahydrofolate reductase (MTHFR) gene and for the A2756G mutation of the methionine synthase (MS) gene, vitamin B12 and folate plasma levels were evaluated in 170 consecutive patients (89 M, 81 F; mean age 41 ± 12 yrs) with documented early-onset thrombosis (89 venous, 69 arterial, 12 both; mean age at first episode 36 ± 11 yrs), and in 182 age- and sex-matched healthy control subjects. Moderate hyperhomocysteinemia (HHcy, tHcy >19.5 µM in men and >15 µM in women) was detected in 45 patients (26.5%) and in 18 controls (9.9%, Mantel-Haenszel OR and 95% C.I. after stratification for arterial or venous thrombosis: 3.25, 1.78–5.91). The 677TT MTHFR genotype was not significantly more prevalent in patients (27.6%) than in controls (21.4%, RR = 1.42; 0.84–2.41), and markedly contributed to HHcy (Mantel-Haenszel RR after stratification for case/control status: 8.29, 4.61–14.9). The 2756GG MS genotype, observed in 4 patients (2.4%) and 8 controls (4.4%), was not associated to HHcy. tHcy was negatively correlated to folate and vitamin B12 levels, with better correlation found in subjects with the 677TT mutation (r = −0.42 and −0.25) than with the 677CC or CT MTHFR genotype (r = −0.37 and −0.11). However, folate was similar in patients and controls and vitamin B12 was higher in patients (460 ± 206 vs. 408 ± 185 pg/ml, p = 0.011). In a generalized linear model, 44% of the variation in tHcy levels was explained by folate and vitamin B12 levels, the MTHFR genotype, gender, and by the interaction of the MTHFR genotype with folate (p ≤0.028); the interactions of vitamin B12 with the MTHFR genotype, gender and patient/control status also significantly contributed to the variation in tHcy levels (p ≤0.028). A 4-week administration of 5-methyltetrahydrofolate (15 mg/day) markedly lowered plasma tHcy in 24 patients with MTHFR 677TT genotype, but the response to treatment correlated with vitamin B12 levels (p = 0.023). Subjects carrying the MTHFR 677TT genotype have higher folate and vitamin B12 requirements irrespective of the A2756G polymorphism of the MS gene. Yet unidentified abnormalities of MS or of any of the enzymes participating in the synthesis of methylated vitamin B12 may play an important role in the phenotypic expression of moderate hyperhomocysteinemia.

Abnormally High Frequency of Inherited Pro-thrombotic Conditions in Subjects with Recurrence of Venous Thrombosis

PHT 3/10 (33.3%) 4/10 (40%) 1/10 (10%) VT 51/244 (20.9%) 31/244 (12.7%)a 38/244 (15.5%) Controls 45/259 (17.4%) 16/259 (6.3%)b 15/259 (5.8%)

Epidemiological observations indicate that high plasma fibrinogen levels are strongly correlated to the frequency of two major thrombotic complications of atherosclerosis: stroke and myocardial infarction. Thrombosis is increasingly recognized as a central mechanism in stroke and myocardial infarction, and fibrinogen is involved in events thought to play a major role in thrombosis. Therefore, elucidation of the relationship between fibrinogen and thrombosis may strengthen the predictive value of this protein and define new interventions against stroke and myocardial infarction. In addition, advances in the understanding of the atherogenic potential of several risk factors of coronary heart disease took advantage of information emerging from the measurement of the factor in population-based studies. Thus, it is conceivable that measuring plasma fibrinogen to predict stroke and myocardial infarction is a major direction to be followed to gain insight into the thrombogenic potential on this protein and inspire new strategies against thrombotic complications of atherosclerosis.