Stefania Vacquer

Increased survival and reversion of iron-induced cardiac disease in patients with thalassemia major receiving intensive combined chelation therapy as compared to desferoxamine alone.

Myocardial iron overload is the leading cause of death in patients with beta-thalassemia major. An intensification monotherapy with deferoxamine (DFO) as well as a combination therapy with DFO and deferiprone (DFP) reduces myocardial iron and improves cardiac function. However, the prognosis for thalassemia major patients with established cardiac disease switched from DFO monotherapy to combined DFP/DFO chelation is unknown. Twenty-eight thalassemia major patients with cardiac disease were enrolled in a prospective study lasting 42+/-6 months. Fifteen (9 high-ferritin and 6 low-ferritin) were placed on DFP/DFO (DFP, 75 mg/kg t.i.d.; DFO, 40-50mg/kg over 8-12h at night 5-7 days/week), while 13 (5 high- and 8 low-ferritin) received DFO alone. No cardiac events were observed among high-ferritin patients on combination therapy, whereas 4 cardiac events (p=0.0049), including three deaths, occurred in high-ferritin patients on DFO monotherapy. These findings demonstrate that in thalassemia major patients with well-established cardiac disease combined iron-chelation therapy with DFP/DFO is superior to DFO monotherapy.

Anemia in beta-thalassemia patients targets hepatic hepcidin transcript levels independently of iron metabolism genes controlling hepcidin expression.

In thalassemia patients, hepcidin mRNA expression was inversely related to erythroid activity, indicating that erythroid marrow expansion inhibits hepatic production of this peptide. Thalassemia associates anemia and iron overload, two opposite stimuli regulating hepcidin gene expression. We characterized hepatic hepcidin expression in 10 thalassemia major and 13 thalassemia intermedia patients. Hepcidin mRNA levels were decreased in the thalassemia intermedia group which presented both lower hemoglobin and higher plasma soluble transferrin receptor levels. There was no relationship between hepcidin mRNA levels and those of genes controlling iron metabolism, including HFE, hemojuvelin, transferrin receptor-2 and ferroportin. These results underline the role of erythropoietic activity on hepcidin decrease in thalassemic patients and suggest that mRNA modulations of other studied genes do not have a significant impact.

High prevalence of thyroid dysfunction in adult patients with β-thalassemia major submitted to amiodarone treatment

Amiodarone may induce hyper- or hypothyroidism. Patients with β-Thalassemia Major (β-Thal) have an increased prevalence of primary hypothyroidism and often require amiodarone for hemosyderotic cardiomyopathy. Aim of this study was to retrospectively evaluate thyroid function in β-Thal adult patients on long-term amiodarone. The study group consisted of twenty-two (21 males, 1 female; age: 23-36 yr) β-Thal patients submitted to long-term (3-48 months) amiodarone therapy from January 1991 to July 1996. Controls included 73 β-Thal patients (23 males and 50 females aged 25-35 yr) not treated with amiodarone. In all cases serum free thyroid hormones, thyrotropin and thyroid autoantibodies were evaluated. A higher prevalence of overt hypothyroidism (5/22 [22.7%]) as compared to controls (3/73 [4.1%], p=0.02) was found in β-Thal patients ≤3 months after starting amiodarone, while the prevalence of subclinical hypothyroidism was similar in amiodarone-treated (18.2%) and untreated (15%) β-Thal patients. Overt hypothyroidism resolved spontaneously after amiodarone withdrawal in 1 case, while the remaining patients were maintained euthyroid on amiodarone by L-thyroxine administration. After 21-47 months of amiodarone therapy, 3 patients (13.6%) developed thyrotoxicosis (2 overt and 1 subclinical), which remitted shortly after amiodarone withdrawal. No case of hyperthyroidism was observed in β-Thal controls (p=0.012 vs amiodarone-treated patients). In conclusion, amiodarone administration is often associated in adult β-Thal patients to a rapid progression of the pre-existing subclinical hypothyroidism, but transient thyrotoxicosis may also be observed after a longer period of therapy. These findings should be carefully considered in the management of these patients.

Thalassemia intermedia is associated with a proatherogenic biochemical phenotype

OBJECTIVE Unlike beta thalassemia major (β-TM) in which cardiac siderosis represents the leading cause of mortality and morbidity, in beta thalassemia intermedia (β-TI), pulmonary hypertension (PHT) and thrombosis seems to be the major cardiovascular complications. However, the mechanism underlying these complications in β-TI is still unclear. Endothelial dysfunction, the key early event in atherogenesis, is now emerging as an important cardiovascular risk determiner in β-TI patients. Among the factors known to affect endothelial function, iron and cholesterol merit particular consideration in β-TI patients. Therefore, with the aim to extend our knowledge on the mechanisms connecting atherosclerosis to β-TI, in this study, we compared lipid and iron metabolism in serum and in peripheral blood mononuclear cells (PBMCs) from β-TI and β-TM patients and controls. METHODS AND RESULTS In this study the iron status and the lipid profile in serum and in peripheral blood mononuclear cells (PBMCs) of 22 adult β-TI patients were examined, and compared with 70 adult β-TM, and 50 age-matched controls. Despite the great variability, levels of serum iron and transferrin saturation were significantly higher in β-TI compared to both controls and β-TM. By contrast, transferrin and hepcidin levels were lower in β-TI patients. Changes in serum indicators in β-TI patients were associated with altered expressions in PBMCs of hepcidin and IL-1α, involved in some way in the regulation of iron homeostasis. In addition β-TI exhibited a reduction of total and high density lipoprotein cholesterol in serum and of neutral cholesterol ester hydrolase in PBMCs, and an increase of cytoplasmic neutral lipids and mRNA levels of acetyl-coenzymeA:cholesterol acyltransferase. CONCLUSIONS Taken together, these findings provide experimental support for the idea that β-TI patients exhibit a proatherogenic biochemical phenotype which may contribute to enhance cardiovascular risk in these subjects.

Renal function in patients with β-thalassaemia major: a long-term follow-up study

BACKGROUND Little information is available about the kidneys involvement in patients with β-thalassaemia major (TM). In particular, there are no studies reporting the outcome of renal function over time. METHODS In this retrospective study, we evaluated the changes in estimated glomerular filtration rate (eGFR) in 81 adult patients with TM followed for 10 years. Only patients who had an eGFR of >90 mL/min/1.73 m(2) at presentation were admitted to the study. All patients were regularly followed for at least 10 years. RESULTS At 10 years, 66 patients showed a mild decline in eGFR that remained, however, within a normal range (from 119.9 to 113.6 mL/min/1.73 m(2), P = 0.636). In the remaining 15 patients (18.5%), eGFR decreased to <90 mL/min (from 98.1 to 78.2 mL/min/1.73 m(2); P = 0.004). The repeated-measures models showed that the decline in eGFR over time was significantly higher (P = 0.0068) in patients with baseline phosphaturia >1000 mg/24 h (P = 0.0068), while eGFR tended to decline more rapidly in patients with baseline uricuria >700 mg/24 h than in those with lower uricuria (P = 0.0783). Univariate Coxs proportional regression models showed that abnormal levels of calcaemia were associated with the risk of kidney damage [hazard ratio (HR) 0.30, 95% confidence interval 0.09-0.97 for calcaemia 8.4-10.2 mg/dL versus HR not estimable for calcaemia <8.4 or >10.2 mg/dL]. CONCLUSIONS In most adults with TM, the eGFR tends to remain within a normal range after 10 years. However, patients with elevated phosphaturia, elevated uricuria and/or abnormal levels of calcaemia show a significant decline in eGFR over time, suggesting that tubular damage acquired in childhood caused by either TM or its treatment may eventually result in abnormal eGFR. Further studies in a larger cohort of TM patients are needed to further elucidate the long-term impact of TM on renal function.

Evidence for a proatherogenic biochemical phenotype in beta thalassemia minor and intermedia.

The purpose of this study was to focus on pathophysiological mechanisms linking β-thalassemia intermedia (β-TI) and minor (β-TMI) with cardiovascular risk. Iron status, prooxidant-antioxidant balance and lipid profiles in serum, and lipid content in peripheral blood mononuclear cells (PBMCs) were evaluated in 20 β-TMI subjects, 22 β-TI patients and in 30 nonthalassemic blood donors. The mRNA levels of some genes involved in the regulation of iron and cholesterol metabolism were also determined. In β-TI and in β-TMI, serum iron, prooxidant-antioxidant ratio, transferrin saturation and erythropoietin levels were higher, while transferrin and hepcidin were lower compared to controls. Hepcidin and interleukin-1α mRNA levels were found to be reduced in β-TI- and β-TMI-PBMCs, while those of tumor necrosis factor alpha were increased. A reduction in high-density lipoprotein cholesterol in serum and an accumulation of neutral lipids coupled with increased mRNA levels of acetyl-coenzyme A:cholesterol acyltransferase and decreased neutral cholesterol ester hydrolase in PBMCs were also observed in β-TI and β-TMI compared to controls. Taken together, these findings provide experimental support for the idea that not only β-TI patients but also β-TMI have a proatherogenic biochemical phenotype which may contribute to increase their cardiovascular disease risk.

Human Immunodeficiency Virus and β-thalassemia Major: A “Competition of Guilt” for Pulmonary Arterial Hypertension. Report of A Case and A Review of the Literature

We report a case of a 43-year-old woman, affected by human immunodeficiency virus (HIV) and β-thalassemia major (β-TM), adequately treated with antiretroviral and transfusion-chelation therapy, that develops progressive right ventricular dysfunction due to severe pulmonary arterial hypertension (PAH), in absence of symptoms. The existence of both HIV and β-TM cardiomiopathy has recently been reported, but how these two diseases have a “competition of guilt” for creating PAH is still to be understood. The main physiopathological principles regarding HIV and β-TM associated PAH are reviewed. The possible interplay between these two different pathologies is discussed.

CMR survey in Thalassemia Intermedia patients

Results One-hundred and eighty-eight (74.6%) patients showed no MIO in any segment, 56 (22%) had an heterogeneous distribution (52 with global heart T2*≥20 ms), and 8 (0.3%) showed an homogeneous MIO. Left ventricular (LV) and right ventricular (RV) dilatations were present in 113 (45%) and in 49 (19%) patients, respectively. LV dysfunction was present in the 18.0% of the cases while RV dysfunction in the 3.63%. High LV mass indexes were present in 22 (8.7%) patients. Fifty-two/227 (22.9%) patients showed myocardial fibrosis. Myocardial fibrosis was associated to LV dysfunction (P = 0.001) and high mass indexes (P = 0.038). One-hundred and fourteen patients were non-transfusion dependent (transfusion requirements absent or sporadic) while 138 patients were transfusion-dependent (regular transfusions). The mean age at start of chronic transfusions was 11.8 ± 12.3 years. Table 1 shows the comparison between the two groups. Non-transfusion-dependent patients showed significantly higher global heart T2* values and MIO with a global heart T2* < 20 ms was detected in two of them (one requiring occasional blood transfusions and one non transfused). Biventricular end-diastolic volume index, stroke volume index, left ventricular (LV) mass index, and LV cardiac index were significantly higher in the non-transfusion dependent group.