Thromboembolic (TE) events have been frequently reported in β-thalassemic patients in association with known risk factors such as diabetes, complex cardiopulmonary abnormalities, hypothyroidism, liver function anomalies, and postsplenectomy thrombocytosis. In a recent survey involving 9 Italian thalassemic centers, we identified 32 patients with TE episodes in a total of 735 subjects, of whom 683 had thalassemia major and 52 thalassemia intermedia, corresponding to 3.95 and 9.61%, respectively. There was a great variation in localization: the main one (16/32) was CNS, with a clinical picture of headache, seizures and hemiparesis. Other localizations were the pulmonary (3 patients), mesenteric (1 patient) and portal (2 patients) sites. There were 6 cases of deep venous thrombosis (2 in the upper limbs, 4 in the lower ones). Intracardiac thrombosis was found in 2 subjects and clinical and laboratory signs of DIC were observed in 2 others during pregnancy. Since our patients with TE events present a statistically significantly higher incidence of associated dysfunction (cardiomyopathy, diabetes, liver function anomalies, hypothyroidism) than those without TE events (50 vs. 13.8%), we suggest close monitoring of those patients who are at higher risk of developing TE events because of the presence of one or more of these predisposing factors.

In patients with betao thalassaemia from Ferrara, beta globin mRNA sequences are either absent or structurally abnormal while in betao thalassaemia in Catania, beta globin mRNA sequences are present. In deltabeta thalassaemia there is a deletion of beta-like globin genes, while in betao Catania DNA, no beta globin gene deletion is detectable.

Osteoporosis in beta-thalassemia major has emerged as a topic of interest since optimized transfusion regimens have increased life expectancy and quality in these patients. Although the pathogenesis of thalassemic osteopathy is multifactorial, the evidence of an increased resorption phase suggests that the use of antiresorptive drugs such as bisphosphonates can be considered a valuable therapeutic strategy to reduce bone turnover and the risk of fragility fractures. We compared the effects of long-term cyclical clodronate therapy (300 mg intravenous infusion every 3 weeks for 2 years) and of an active placebo (calcium 1 vitamin D) on bone mass and bone turnover in 30 male patients with beta-thalassemia major. We also tested the possibility of using quantitative ultrasound (QUS) for assessing bone involvement in thalassemic osteopenia and in monitoring the response to antiresorptive therapy. Broadband ultrasound attenuation (BUA) was significantly reduced in patients with beta-thalassemia major as compared to healthy controls. In calcium and vitamin D-treated patients, a significant decline in spine, femoral, and total body areal bone density was observed. In the patients given intravenous clodronate we measured a substantial stability of bone mass, which was not significantly changed at the end of the study. The urinary excretion of deoxypyridinoline (a marker of bone resorption) showed a progressive significant decline throughout the study period in clodronate-treated patients. No significant change was observed in BUA values in both groups of patients. These results indicate that intermittent intravenous clodronate administration was not able to increase areal bone density in our thalassemic patients. Moreover, this is the first study to have assessed the usefulness of broadband ultrasound measurements in beta-thalassemia major.

SUMMARY Lymphocyte subpopulations were studied in 20 hypertransfused patients with ,B-thalassaemia major, some of whom had been splenectomised. B-lymphocytes were normal but T-lymphocytes were decreased in all patients. The T-cell count was lower in the splenectomised patients than in the nonsplenectomised ones. In the former, the active rosette-forming lymphocytes were also diminished, but the difference was not significant. In all patients the percentage of null cells was greater and the activity of K-cells increased compared with controls.

Summary:exclusion of those who had clinically significant symptoms and laboratory evidence of HBV infection. Therefore, all thalassemic patients, with the only exception being those We evaluated the immune status with respect to HBV and the immune response to readministration of HBV who had undergone allogeneic bone marrow transplantation (BMT), can be considered as protected against HBV infecvaccine in a series of 20 patients with homozygous ␤-thalassemia, aged 6-23 years (mean age: 13.0 ± 4.2) who tion. BM-transplanted patients must be considered as immunodeficient subjects and to be at increased risk of conhad undergone allogeneic bone marrow transplantation (BMT). Thirteen of them (group A), had received three tracting infectious diseases. 4,5 The immunosuppressive therapy that is used to prevent rejection and for the prophylaxis doses of plasma-derived HBV vaccine from 7 to 5 years before BMT and 4-5 weeks after the last dose of vacof graft-versus-host disease (GVHD) induces an almost complete loss of all immune functions. 4 Moreover, the cine, they had had high serum levels of HBV antibodies (anti-HBs). The remaining seven patients (group B) had immunity conferred by the donor's memory cells is transient and negligible 6 since the donor's memory cells engraft had clinical symptoms and laboratory evidence of HBV infection in childhood with markedly elevated serum of with difficulty, their numbers decline quickly according to their different degree of cellular maturity at the time of the anti-HBs. Before revaccination, a significantly lower percentage of patients (P Ͻ 0.005) with seropositive levtransplant 7 and a long time period is required for restoration of their complete function. 8 In addition, serum levels of els of anti-HBs was observed in group A than in group B. After administration of the second dose of HBV vacimmunoglobulins in these patients become normal within times ranging from 3-6 months to 1-2 years. 9 cine the percentage of subjects with protective levels of anti-HBs rose to 100% in both groups of patients evenThis study was performed to assess the immune status against HBV in BM-transplanted beta-thalassemic patients if the geometric mean of titers of anti-HBs increased more significantly in group B patients than in group A.who had previously been given HBV vaccine and in those who had had clinically significant symptoms and laboratory We conclude that the serum levels of anti-HBs afforded by HBV vaccine administered from 7 to 5 years preevidence of HBV infection, in order to evaluate if revaccination in these subjects is indicated and effective. In fact, viously are very low and probably non-protective in most ␤-thalassemic patients after allogeneic BMT, and these patients, although no longer treated by regular blood transfusion after successful BMT, are in the age range most that at least two doses of HBV vaccine should be readministered from 18 to 24 months after BMT to achieve susceptible to HBV infection 10 and live in a country where HBV is still quite prevalent. 1 adequate and l...