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Myeloproliferative neoplasms are most commonly associated with venous thrombosis. Up to 60% of patients experience a thrombotic event in their lifetimes, including stroke or myocardial infarction. It is unclear whether pathogenetic factors linking essential thrombocythemia (ET) and polycythemia vera (PV) to thrombotic complications do play a role in the risk of coronary artery disease (CAD). We aimed to assess coronary flow reserve (CFR) as a marker of coronary microvascular function in asymptomatic patients with ET and PV. Fifty-two patients with ET (M/F 13/39, age 61 ± 7 years) and 22 patients with PV (M/F 13/9, age 60.4 ± 13 years) without clinical evidence of heart disease, and 50 controls matched for age and gender were studied. None had CAD. All control subjects were asymptomatic with no history of heart disease. CFR in the left anterior descending coronary artery was detected by transthoracic Doppler echocardiography, at rest, and during adenosine infusion. In patients with ET and PV, CFR was lower than in controls (2.9 ± 0.94 and 2.2 ± 0.7 vs. 3.8 ± 0.7, P 0.004 and P 0.0001 respectively). The prevalence of CFR ≤ 2.5 was higher in patients with ET (20 cases, 38.5%) and PV (15 cases, 68.2%) compared with controls (4.1%) (P 0.0001). Severe CFR (CFR 2) impairment was found in eight patients with ET (15.4%), in nine patients with PV (40.9%), and in none of control subjects. The mutation of JAK2 gene was associated with abnormal CFR. Asymptomatic patients with ET and PV have coronary microvascular dysfunction in the absence of clinical conditions suggesting CAD.

Veno-occlusive disease (VOD) is a major complication following hematopoietic stem cell transplantation (HSCT). Its diagnosis is based on clinical criteria, which have a limited sensitivity. Increased plasminogen activator inhibitor-1 (PAI-1) levels have been suggested as a marker of VOD. We aimed to prospectively evaluate how the fibrinolytic parameters behaved to discriminate VOD from other liver disorders occurring after HSCT in a pediatric population.A total of 195 HSCT were performed on 161 children and VOD complicated 11 cases (6.8%). Alanine aminotransferase, total bilirubin, PAI-1 antigen (PAI-1:Ag) and activity, t-PA antigen, D-dimer, prothrombin time, activated partial thromboplastin time, antithrombin, fibrinogen, and platelet counts were measured in 105 HSCT before and then weekly for 1 month after HSCT.An early, significant increase in the fibrinolytic parameters was seen in patients who developed VOD, even before VOD was diagnosed clinically, by comparison with patients without complications or those with non-VOD liver disorders. The combined increase in bilirubin, D-dimer, and PAI-1:Ag levels beyond the normal range distinguished VOD cases from other liver complications with a high sensitivity and specificity.Our study demonstrates that fibrinolytic tests can help diagnose VOD after HSCT in the pediatric population.

SummarySevere type I plasminogen deficiency is the underlying cause of ligneous conjunctivitis, a rare disease characterized by wood-like pseudomembranes developing on the ocular and extraocular mucosa. Two unrelated female patients with ligneous conjunctivitis and moderate hypoplasminogenemia are described. Being of fertile age, they were treated with oral contraceptives, which determined a marked increase in plasminogen levels. Moreover, a palpebral pseudomembrane stopped growing in one patient and disappeared completely in the other while on the estroprogestinic treatment. In patient n.2,who also suffered from von Willebrand’s disease, prior Cushing’s disease induced an increase in both von Willebrand factor and plasminogen levels, which dropped after curative hypophysectomy. Genetic plasminogen study showed a 19Lys>Glu mutation in a heterozygous state in the first proposita and in a homozygous state in the second proband. In addition, both index patients were homozygous for a new intron F-14T>G mutation, which was found to reduce the acceptor splicing site prediction score.In conclusion, oral contraceptive therapy may improve plasminogen deficiency and deserves attention as an alternative therapeutic approach in selected cases of ligneous conjunctivitis with low, but not absent, plasminogen synthesis.

To establish the prevalence of antibodies against beta2-glycoprotein I (beta2GPI) in unselected patients with venous thromboembolism, as well as the association with antiphospholipid antibodies (aPL) and a history of previous thromboembolism, we investigated the presence of these antibodies in 227 consecutive patients with acute deep vein thrombosis or pulmonary embolism, of whom 63 were carriers of aPL with or without lupus anticoagulant (LA), and seven were carriers of LA alone. The presence of antibodies against beta2GPI was demonstrated in 19 patients [8.4%; 95% confidence interval (CI), 4.5-11.3%]. All of them belonged to the group of 63 patients with aPL (30.2%). A history of a previous thromboembolism was identified in 11 of the 19 patients with anti-beta2GPI antibodies (57.9%) and in 45 of the 208 patients without these antibodies [21.6%; odds ratio (OR)=4.98; 95% CI, 1.89-13.1; p0.0005]. In the subgroup of patients with aPL and/or LA, the rate of recurrent thromboembolism among patients with anti-beta2GPI antibodies (11 of 19, 57.9%) was significantly higher than that observed in patients without these antibodies (15 of 51, 29.4%; OR=3.3; 95% CI, 1.1-9.83; p=0.28). We conclude that in patients with acute venous thromboembolism the prevalence of antibodies against beta2GPI is unexpectedly high. The presence of these antibodies seems to identify a subgroup of patients with antiphospholipid antibodies who have a peculiarly high risk of thrombotic recurrences. Further prospective studies are indicated to better define the role of anti-beta2GPI antibodies in the development of recurrent thromboembolism.

In the present study, the prevalence of thromboembolic events in patients suffering from type I plasminogen deficiency was evaluated. One hundred and twelve affected subjects belonging to twenty-eight kindreds were gathered from the literature and from personal observations. The incidence of thrombosis found in this group was compared with those seen in: a) 86 unaffected family members; b) 100 hospitalized patients; c) 100 outpatient clinic patients. In the latter two groups, congenital clotting disorders were excluded. Thrombotic manifestations were found in 25.8% of patients with plasminogen deficiency, a figure which was statistically different from those found in unaffected family members (1.16%, p0.001), hospitalized patients (3%, p0.001) and outpatient clinic patients (5%, p0.001). In twenty-four kindreds with hypoplasminogenemia, data concerning the actuarial ages at first thrombotic event were available for construction of thrombosis-free survival curves by the Cutler-Ederer method. The difference between the two curves, corresponding to affected and unaffected family members respectively, were statistically significant (p0.01). In conclusion, although the incidence of thromboembolic events in type I plasminogen deficiency is certainly lower than that described in other congenital clotting disorders such as AT III, protein C and protein S, patients with hypoplasminogenemia should be considered at risk for thrombosis, particularly when triggering factors are present.