Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Total cholesterol, triglycerides (TG), LDL-cholesterol, HDL-cholesterol, alpha-lipoprotein (LP) (HDL-LP), pre-beta-LP (VLDL-LP) and beta-lipoprotein (LDL-LP) were measured in the blood of 104 patients with major and intermedia form of beta-thalassaemia and 112 control subjects, mean age +/- SD 10.2 +/- 3.5 and 9.1 +/- 3.8 years, respectively. Cholesterol, LDL- and HDL-cholesterol were significantly decreased and TG was significantly increased in the patients compared to the control subjects. TG values in male patients were significantly higher than in male control subjects, but no differences were found in females. Patients with major and intermedia forms of beta-thalassaemia and chronic hepatitis C have significantly lower values of cholesterol and beta-LP and higher values of HDL-cholesterol than patients without hepatitis C. An increase of HDL-cholesterol and alpha-LP was found in patients with diabetes mellitus or impaired glucose tolerance (IGT) compared to patients without IGT. In the thalassaemic patients there was an increase of TG and pre-beta-LP and a decrease of HDL-cholesterol and alpha-LP with increasing ferritin values. There was a positive correlation of the patients' age with TG and pre-beta-LP whereas no such correlation was found in the control subjects. It appears, therefore, that many factors as iron overload, liver injury, hormonal disturbances and aging affects lipids and LP pattern in patients with major and intermedia form of beta-thalassaemia.
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PMID:beta-Thalassaemia and factors affecting the metabolism of lipids and lipoproteins. 1465 51

Hepatocellular carcinoma (HCC) frequently complicates hepatic cirrhosis secondary to viral infection or iron overload. Therefore, patients affected by thalassaemia syndromes have a theoretically high risk of developing the tumour. We collected data on patients attending Italian centres for the treatment of thalassaemia. Twenty-two cases of HCC were identified; 15 were male. At diagnosis, the mean age was 45 +/- 11 years and the mean serum ferritin was 1764 +/- 1448 microg/l. Eighty-six percent had been infected by hepatitis C virus. Nineteen of 22 cases were diagnosed after 1993, suggesting that this problem is becoming more frequent with the aging population of thalassaemia patients.
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PMID:Hepatocellular carcinoma in the thalassaemia syndromes. 1467 16

Hepatitis C virus (HCV) infection is a common cause of liver disease in thalassemia major patients in Western, especially Mediterranean, countries. Its significance in thalassemic patients from Southeast Asia has not been critically evaluated. In this report, we describe our study of the prevalence of HCV infection among Thai patients with thalassemia. The relationships of the infection to blood transfusion and the infection's effects on liver function have also been determined. Of the 104 patients studied, 21 (20.2%) tested positively by enzyme immunoassay for anti-HCV antibody, whereas only 2 patients (2%) had the hepatitis B surface antigen. There was no significant relationship between the presence of anti-HCV antibodies and the number and frequency of blood transfusions. In fact, 2 patients (10%) who tested positive for anti-HCV antibodies had never received transfusions. Patients with anti-HCV antibodies had significantly abnormal liver functions, such as higher levels of serum aspartate aminotransferase (SGOT) and alanine aminotransferase (SGPT) and lower levels of serum albumin, compared with patients without anti-HCV antibodies (P = .021, .017, and .004, respectively). However, there were also significant correlations between iron status as indicated by transferrin saturation or serum ferritin levels and SGOT, SGPT, and gamma-glutamyltransferase (GGT) levels. Moreover, abnormal liver function as represented by elevated levels of SGOT, SGPT, GGT, and serum alkaline phosphatase was observed more frequently in patients with iron overload than in patients with a lower degree of iron burden. The presence of HCV did not alter the effects of iron overload on liver function. The findings suggest that both HCV and iron overload are the main causes of abnormal liver function in Thai patients with thalassemia. The treatment of both problems, if coexisting in patients with thalassemia, is required to prevent progression to chronic liver disease.
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PMID:Prevalence and clinical significance of hepatitis C virus infection in Thai patients with thalassemia. 1468 98

Treatment of patients with beta-thalassemia major has improved dramatically during the past 40 years; however, the current clinical status of these patients remains poorly characterized. We performed a cross-sectional study of 342 patients in the Registry of the National Institutes of Health-sponsored Thalassemia Clinical Research Network. Evidence of hepatitis C exposure was present in 35% of tested patients, was associated with age, and had a rate of spontaneous viral clearance of 33%. Ferritin levels ranged from 147 to 11 010 ng/mL (median, 1696 ng/mL). Median hepatic iron content was 7.8 mg/g dry weight and 23% of patients had values of 15 mg/g dry weight or higher. No patients 15 years or younger and 5% of patients aged 16 to 24 years had heart disease requiring medication. Ten percent had cirrhosis on biopsy. Endocrinologic complications were common among adults. Seventy-four (22%) patients had recent implantable central venous access devices (CVADs) placed. Among 80 episodes of bacteremia in 38 patients, 90% were attributable to the CVAD. Among 330 patients who had received deferoxamine chelation therapy, 224 (68%) reported no complications. We conclude that hepatitis C, iron-related organ dysfunction, and complications of iron chelation therapy are strongly age-dependent in North American patients with beta-thalassemia.
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PMID:Complications of beta-thalassemia major in North America. 1498 52

New developments in the epidemiology, treatment and prognosis of thalassemia have dramatically altered the approach to the care of affected patients, and these developments are likely to have an even greater impact in the next few years. Demographic changes have required an awareness and understanding of the unique features of thalassemia disorders that were previously uncommon in North America but are now seen more frequently in children and recognized more consistently in adults. New methods for measuring tissue iron accumulation and new drugs to remove excessive iron are advancing two of the most challenging areas in the management of thalassemia as well as other transfusion-dependent disorders. Improved survival of patients with thalassemia has given new importance to adult complications such as endocrinopathies and hepatitis that have a major impact on the quality of life. This chapter describes how these changes are redefining the clinical management of thalassemia. In Section I, Dr. Renzo Galanello describes recent advances in iron chelation therapy. Several new chelators are either licensed in some countries, are in clinical trials or are in the late stages of preclinical development. Some of these iron chelators, such as deferiprone (DFP) and ICL670, are orally active. Others, such as hydroxybenzyl-ethylenediamine-diacetic acid (HBED) and starch deferoxamine, require parenteral administration but may be effective with less frequent administration than is currently required for deferoxamine. Chelation therapy employing two chelators offers the possibility of more effective removal of iron without compromising safety or compliance. Other strategies for chelation therapy may take advantage of the ability of particular chelators to remove iron from specific target organs such as the heart and the liver. In Section II, Dr. Dudley Pennell addresses cardiac iron overload, the most frequent cause of death from chronic transfusion therapy. The cardiac complications related to excessive iron may result from long-term iron deposition in vulnerable areas or may be due to the more immediate effects of nontransferrin-bound iron. Cardiac disease is reversible in some patients with intensive iron chelation therapy, but identification of cardiac problems prior to the onset of serious arrhythmias or congestive heart failure has proven difficult. New methods using magnetic resonance imaging (MRI) have recently been developed to assess cardiac iron loading, and studies suggest a clinically useful relationship between the results using these techniques and critical measures of cardiac function. Measurements such as T2* may help guide chelation therapy in individual patients and may also enhance the assessment of new chelators in clinical trials. The use of MRI-based technology also holds promise for wider application of non-invasive assessment of cardiac iron in the management of patients with thalassemia. In Section III, Dr. Melody Cunningham describes some of the important complications of thalassemia that are emerging as patients survive into adulthood. Hepatitis C infection is present in the majority of patients older than 25 years. However, antiviral therapy in patients with thalassemia has been held back by the absence of large clinical trials and concern about ribavirin-induced hemolysis. More aggressive approaches to the treatment of hepatitis C may be particularly valuable because of the additive risks for cirrhosis and hepatocellular carcinoma that are posed by infection and iron overload. Thrombosis is recognized with increasing frequency as a significant complication of thalassemia major and thalassemia intermedia, and pulmonary hypertension is now the focus of intense study. Risk factors for thrombosis such as splenectomy are being identified and new approaches to anticoagulation are being initiated. Pregnancies in women with thalassemia are increasingly common with and without hormonal therapy, and require a better understanding of the risks of iron overload and cardiac disease in the mother and exposure of the fetus to iron chelators. In Section IV, Dr. Elliott Vichinsky describes the dramatic changes in the epidemiology of thalassemia in North America. Hemoglobin E-beta thalassemia is seen with increasing frequency and poses a particular challenge because of the wide variability in clinical severity. Some affected patients may require little or no intervention, while others need chronic transfusion therapy and may be appropriate candidates for hematopoietic stem cell transplantation. Enhancers of fetal hemoglobin production may have a unique role in Hb E-beta thalassemia since a modest increase in hemoglobin level may confer substantial clinical benefits. Alpha thalassemia is also being recognized with increasing frequency in North America, and newborn screening for Hemoglobin Barts in some states is leading to early detection of Hb H disease and Hb H Constant Spring. New data clarify the importance of distinguishing these two disorders because of the increased severity associated with Hb H Constant Spring. The use of intrauterine transfusions to sustain the viability of fetuses with homozygous alpha thalassemia has created a new population of patients with severe thalassemia and has raised new and complex issues in genetic counseling for parents with alpha thalassemia trait.
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PMID:Thalassemia. 1556 74

Twelve thalassaemia major patients have been given deferiprone 75 mg/kg body weight daily as iron chelation therapy for 5 years. Their ages ranged from 18 to 34 years (mean 24.2) at the end of the study. Two patients were hepatitis C virus (HCV) mRNA positive and a further 5 were positive for HCV antibody. The mean serum ferritin level fell significantly from 4,302 +/- 2,245 microg/l SD at baseline to 3,032 +/- 1,155 microg/l at 2 years (p = 0.037) and 2,229 +/- 1,070 microg/l (p = 0.007) at 5 years. At the end of the study, liver iron ranged from 3.59 to 23.7 mg/g dry weight (mean 11.9 +/- 5.4), 3 patients having levels >15 mg/g. There was no significant change in serum AST levels, but ALT levels fell significantly at 2 years (p = 0.019) and 5 years (p = 0.001). Liver biopsy at the end of the study showed no evidence of hepatic fibrosis caused by deferiprone. Cardiac studies showed no overall change in left ventricular ejection fraction but a significant improvement in isovolumic relaxation time (p = 0.045). We conclude that in this albeit small group of thalassaemia major patients, deferiprone was a safe long-term method of iron chelation. In a minority, higher doses of deferiprone or a combination with desferrioxamine would be needed to lower liver iron below 15 mg/g.
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PMID:Five-year trial of deferiprone chelation therapy in thalassaemia major patients. 1556 27

Hepatitis C virus is considered to be the main aetiological agent responsible for the occurrence of post-transfusion hepatitis. Patients with thalassaemia acquire hepatitis most often from viruses contracted through blood transfusions. The present study was undertaken to evaluate the prevalence of hepatitis C virus (HCV) in thalassaemic patients with multiple blood transfusions. The association of HCV seropositivity with number of blood transfusions and liver enzyme profile was also analysed. The study group consisted of fifty patients (40 males and 10 females) attending the thalassaemic unit of Lok Nayak Hospital, a tertiary care hospital at Delhi, within the age group of 1-25 years. Thirty patients (60%) were found to be seropositive for HCV antibodies while one patient (2%) was co-infected with HCV antibodies and hepatitis B surface antigen. Study of liver enzyme profile showed aspartate aminotransferase levels to be significantly higher, although the level of serum alanine aminotransferase, alkaline phosphatase, total protein, bilirubin and albumin were not significantly altered in these patients. It is inferred from this study that 60% of the thalassaemics were infected with HCV and this was directly related to the number of blood transfusions received by them. The regularised national blood policy followed by blood banks for providing safe blood along with better screening method of donated blood in blood banks would bring down the incidence of hepatitis C in such high risk group.
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PMID:Anti-HCV seropositivity among multiple transfused patients with beta thalassaemia. 1600 15

Historically, fractures are cited as a frequent problem in patients with Thalassemia prior to optimization of transfusion and chelation regimens. The aim of this study was to determine the prevalence of fractures in a contemporary sample of North American patients with Thalassemia. The North American Thalassemia Clinical Research Network (TCRN) database registry was used to gather historical data on 702 patients with common alpha and beta-Thalassemia diagnoses including Thalassemia Major (TM), Intermedia (TI), E/Beta, homozygous alpha Thalassemia (AT), Hemoglobin H disease (HbH) and HbH with Constant Spring (HbH/CS), who consented to a medical record chart review. Bone mineral density (BMD) measurements by DXA were available for review in a subgroup of patients (n = 312). The overall fracture prevalence among all Thalassemia syndromes was 12.1%, equally distributed between females (11.5%) and males (12.7%). Fractures occurred more frequently in TM (16.6%) and TI (12.2%) compared to E/Beta (7.4%) and alpha (2.3%). Prevalence increased with age (2.5% ages 0-10 years, 7.4% ages 11-19 years, 23.2% ages >20 years) and with use of sex hormone replacement therapy (SHRT) (P < 0.01). On average, BMD Z and T scores were 0.85 SD lower among patients with a history of fractures (mean Z/T score -2.78 vs. -1.93, 95% CI for the difference -0.49 to -1.22 SD, P = 0.02). Presence of other endocrinopathies (i.e. hypothyroidism, hypoparathyroidism and diabetes mellitus), anthropometric parameters, heart disease or hepatitis C were not significant independent predictors of fractures. These data indicate that fractures remain a frequent complication among the aging patients with both TM and TI beta-Thalassemia. However, the fracture prevalence has improved compared to published reports from the 1960s to 1970s. In addition, children with Thalassemia appear to have low fracture rates compared to the general population.
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PMID:Prevalence of fractures among the Thalassemia syndromes in North America. 1629 78

The life expectancy of patients with thalassemia major has significantly increased in recent years, as reported by several groups in different countries. However, complications are still frequent and affect the patients' quality of life. In a recent study from the United Kingdom, it was found that 50% of the patients had died before age 35. At that age, 65% of the patients from an Italian long-term study were still alive. Heart disease is responsible for more than half of the deaths. The prevalence of complications in Italian patients born after 1970 includes heart failure in 7%, hypogonadism in 55%, hypothyroidism in 11%, and diabetes in 6%. Similar data were reported in patients from the United States. In the Italian study, lower ferritin levels were associated with a lower probability of experiencing heart failure and with prolonged survival. Osteoporosis and osteopenia are common and affect virtually all patients. Hepatitis C virus antibodies are present in 85% of multitransfused Italian patients, 23% of patients in the United Kingdom, 35% in the United States, 34% in France, and 21% in India. Hepatocellular carcinoma can complicate the course of hepatitis. A survey of Italian centers has identified 23 such cases in patients with a thalassemia syndrome. In conclusion, rates of survival and complication-free survival continue to improve, due to better treatment strategies. New complications are appearing in long-term survivors. Iron overload of the heart remains the main cause of morbidity and mortality.
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PMID:Survival and complications in thalassemia. 1633 50

Treatment of hepatitis C virus (HCV) in the general population has improved over the last decade. Patients treated with peginterferon alfa (PegIFN) and ribavirin (RBV) combination therapy demonstrate overall 50-55% sustained viral response (SVR) with rates as high as 80% in patients with genotypes 2 and 3. Because RBV induces hemolysis and subsequently increases blood transfusion requirements, combination therapy has been considered contraindicated for hemoglobinopathies. This report reviews the response to interferon alfa and RBV (IFN/RBV) and PegIFN/RBV combination therapies in patients treated in the Northern California Comprehensive Thalassemia Center. A total of six thalassemia major patients were treated with IFN/RBV (n = 5; age: 4-38 years) or with PegIFN/RBV (n = 1; age: 26 years). Quantitative HCV RNA polymerase chain reaction and liver iron level assessment were completed. Transfusion volumes were obtained from patients' medical records. On IFN/RBV combination, four of five patients demonstrated SVR. The one patient on PegIFN/RBV showed end-treatment viral response after 6 months of therapy (genotype 3), but subsequently relapsed. Liver iron pretreatment level ranged from 0.2 to 22 mg/g dry weight, with a mean +/- SD of 7.9 +/- 7.7. Transfusion requirement increased by a median of 43.5% (range: 32-137%). Five of the six patients had liver iron measurements within 1 year following completion of treatment, with quantitative liver iron increasing in two patients by 2.5 mg/g dry weight, decreasing in two patients by 3 and 14 mg/g dry weight, and remaining unchanged in one patient. All patients were able to complete combination therapy, although dose reductions were required. Patients with thalassemia and high iron overload can obtain SVR after combination therapy with rates similar to those in the general population and without significant complications. Although transfusion requirements increased in most patients, iron burden was not necessarily increased.
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PMID:Treatment of hepatitis C virus infection in thalassemia. 1633 77


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