Biomedical subjects
Publications and source records attributed to Anna Meo.
This retrospective one to one matched case-control study was aimed at evaluating risk factors for death in beta-thalassemic patients followed in Italian centers between 1997 and 2001. The mortality risk was lower in patients with good compliance to iron chelation therapy and in those treated with deferiprone.
In this retrospective study, we report the results of the association of a combined phlebotomy program and chelation in hereditary sideroblastic anemia (HSA) to reduce iron overload after bone marrow transplantation (BMT). A male HSA patient, not responding to pyridoxine treatment, was submitted to successful allogeneic BMT. As there was a persistence of a tissue iron overload, a regular phlebotomy program was started followed by chelation. A significant decrease of iron burden was obtained using a combined treatment with deferoxamine (DFO) and deferiprone (L1) in addition to the phlebotomy program. A 10-year follow-up shows a marked decrease in the concentration of serum ferritin, non-transferrin-bound iron (NTBI), liver iron and normal hemoglobin (Hb), which allows the patient to reach and maintain a good quality of life.
We studied a patient with mild beta-thalassaemia major under treatment with the oral chelator deferiprone (DFP or L1) for about 10 yr (L1 veteran). Due to poor compliance with desferrioxamine, the patient started compassionate use of DFP at an age of 23 yr with a serum ferritin of 5200 microg/L. Monitoring iron overload by SQUID biosusceptometry revealed a dramatic decrease of liver iron concentrations from 4500 to 950 microg/g(liver) within 9.5 yr. A good clinical response to chelation treatment with DFP was observed together with an improvement of liver and cardiac function and a reduction in the hepatitis virus load.
UNLABELLED: Osteoporosis represents an important cause of morbidity in adult thalassemic patients, and its pathogenesis has not, as yet, been completely clarified. In our study, we observed that thalassemic patients showed a significantly lower OPG/RANKL ratio than normal subjects. These data are extremely important for the possible therapeutic use of RANKL antagonists such as OPG in thalassemia-induced osteoporosis. INTRODUCTION: Osteoporosis represents an important cause of morbidity in adult thalassemic patients who display increased fracture risk. The etiology of this bone disease is multifactorial, but it is thought that the main role is played by hypogonadism. The mechanisms by which the skeletal effects of sex steroids are mediated are still not fully understood. Recently, two new cytokines, osteoprotegerin (OPG) and RANKL, have been implicated in the pathogenesis of postmenopausal osteoporosis and other metabolic bone diseases. Thus, the aim of this study was to characterize the possible role of the OPG/RANKL system in thalassemia-related bone loss. MATERIALS AND METHODS: We measured, in 30 thalassemic patients and in 20 healthy control subjects, serum OPG and RANKL levels, and determined their correlations with bone turnover markers, BMD, sex steroid levels, erythropoietin, and hemoglobin. RESULTS: Thalassemic patients had an unbalanced bone turnover with an increased resorption phase (shown by high levels of pyridinium cross-links) and a decreased neoformation phase (shown by the slightly low levels of osteocalcin). Moreover, they displayed lower BMD values than controls both at the lumbar and femoral level. As far as the OPG/RANKL system is concerned, thalassemic patients showed no differences in plasma levels of OPG compared with controls, and significantly higher plasma levels of RANKL, with a consequent significantly lower OPG/RANKL ratio. CONCLUSIONS: Our data suggest that, in thalassemic patients, an altered modulation of the OPG/RANKL system, resulting in increased expression of RANKL by stromal or osteoblastic cells, could contribute to the enhanced osteoclastic bone resorption and bone loss characteristic of these patients.
BACKGROUND AND OBJECTIVES: Updated information on liver disease in transfusion-dependent beta-thalassemia is lacking. We conducted a multicenter study within the Cooleycare Group to describe the clinical and histopathological features of liver disease in currently treated thalassemics. DESIGN AND METHODS: Two-hundred and three thalassemics with laboratory signs of liver disease were eligible. Liver biopsy was performed in the 129 (63.5%) who consented (age 26+/-7 years). Biological samples were sent to the central laboratory. RESULTS: Anti-hepatitis C virus (HCV) antibodies were found in 118 patients (91%), 85 (72%) of whom were viremic. Ninety-one patients (70%) had abnormal aminotransferase concentrations. In the 117 liver biopsies that met the criteria for evaluation (88%), the median Ishak's necroinflammatory and fibrosis scores were 4 (range, 0-9) and 2 (range, 0-6), respectively. Significant fibrosis (score >or=3) was found in 53 (45%); 9 (8%) had cirrhosis. At multivariate analysis, necroinflammation was related to HCV viremia, and fibrosis to increased serum aminotransferases, higher iron stores (including serum ferritin, Deugnier's total iron score, and liver iron content) and male gender (p<0.05). In HCV-RNA negative subjects, the median total iron score was 27 (range, 0-52). Iron accumulated in both mesenchymal cells and hepatocytes, and the presence of a lobular gradient was interpreted to indicate intestinal hyperabsorption. INTERPRETATION AND CONCLUSIONS: Transfusion-dependent thalassemics have mild liver necroinflammation, mainly attributable to HCV infection. Significant fibrosis is frequent, and its progression is mostly influenced by iron overload which, with current therapy regimens, may be attributable to both erythrocyte catabolism and iron hyperabsorption.
Sixty-seven homozygous male and female thalassemic patients with different phenotypes, aged between 8 and 33 years, were divided into three groups, according to the severity of their beta-thalassemia (thal) mutations. We investigated whether some co-inherited genetic factors could influence the phenotype. Patients with milder beta-thal defects, homozygotes or compound heterozygotes for the IVS-I-6 (T-->C) or -87 (C-->G) mutations had a milder disease. In addition, determination of the co-inheritance of the -158 (C-->T) G(gamma) polymorphism and the (AT)9T5 repeat motif in the region -540 to -525, 5' to the beta-globin gene, showed that in some patients with severe or mild/severe beta-thal mutations, linked to haplotype III, there was higher Hb F expression. We conclude that in homozygous beta-thal patients, the severity of the mutations is the most important factor influencing the phenotype, but some polymorphisms such as the -158 (C-->T) G(gamma) and (AT)9T5 repeat motif, increasing the Hb F expression and ameliorate the clinical course of the disease.
Beta-thalassemia, the most common hereditary anemia in the Mediterranean area, results from over 200 causative mutations in the beta-globin locus. The aim of this study was to validate a denaturing high-performance liquid chromatography (dHPLC)-based assay for postnatal and prenatal molecular diagnosis of beta-thalassemia in Southern Italy. Sixty beta-thalassemic patients, affected either by thalassemia intermedia or thalassemia major, were analyzed in a blind study. We also carried out prenatal molecular diagnosis in 12 couples at-risk for having affected offspring. Chorionic villi samples were subjected to dHPLC analysis upon molecular characterization of the parental beta-globin alleles. Direct sequence analysis was used to validate each result, showing an accuracy rate of 100% for dHPLC. Overall, our protocol was able to identify the responsible mutations in all 96 analyzed subjects (including 12 prenatals in at-risk pregnancies), detecting the eight most common mutations in Southern Italy. Three rare mutations (one of which, reported here for the first time) that standard mutation detection methods failed to reveal, were also identified. dHPLC assay proved to be a reliable, rapid, and sensitive method for detecting both common and rare mutations within the beta-globin gene. Because of this property our protocol has the potential to be implemented for mutational screening in different areas of high prevalence for beta-thalassemia.