Chronic Blood Transfusion Research Articles

Antigens Protected Functional Red Blood Cells By The Membrane Grafting Of Compact Hyperbranched Polyglycerols

Red blood cell (RBC) transfusion is vital for the treatment of a number of acute and chronic medical problems such as thalassemia major and sickle cell anemia 1-3. Due to the presence of multitude of antigens on the RBC surface (~308 known antigens 4), patients in the chronic blood transfusion therapy develop alloantibodies due to the miss match of minor antigens on transfused RBCs 4, 5. Grafting of hydrophilic polymers such as polyethylene glycol (PEG) and hyperbranched polyglycerol (HPG) forms an exclusion layer on RBC membrane that prevents the interaction of antibodies with surface antigens without affecting the passage of small molecules such as oxygen ,glucose, and ions3. At present no method is available for the generation of universal red blood donor cells in part because of the daunting challenge presented by the presence of large number of antigens (protein and carbohydrate based) on the RBC surface and the development of such methods will significantly improve transfusion safety, and dramatically improve the availability and use of RBCs. In this report, the experiments that are used to develop antigen protected functional RBCs by the membrane grafting of HPG and their characterization are presented. HPGs are highly biocompatible compact polymers 6, 7, and are expected to be located within the cell glycocalyx that surrounds the lipid membrane 8, 9 and mask RBC surface antigens10, 11.

Red cell and human leukocyte antigen alloimmunization in candidates for renal transplantation: a reality

Red cell and human leukocyte antigen alloimmunization in candidates for renal transplantation: a reality

Stroke recurrence in Nigerian children with sickle cell disease treated with hydroxyurea

To compare the outcome after a first clinical stroke, following treatment with and without hydroxyurea (HU).A retrospective review of a cohort of Nigerian children with SCD, who had suffered a first stroke, was carried out. Outcomes in the group of children who received and did not receive HU were compared.Thirty two children presented with stroke and one died of haemorrhagic stroke at presentation. All the children had haemoglobin SS phenotype, and ischaemic stroke was the predominant form seen. Mean age at first clinical stroke was 7 years, 7 months (SD=2 years, 4 months). Thirteen children received HU while 18 declined HU therapy. Maximum dose of HU ranged from 20-25 mg/kg/ day. The secondary stroke incidence of 7/100 person years in the HU group was significantly lower than the 28/100 person years in the non-HU group (P=0.001, OR 3.808, 95% CI 1.556, 9.317). Children who did not receive HU were more likely to drop out of school and to have moderate-severe motor disabilities requiring caregiver assistance for daily living.In settings where facilities for chronic blood transfusion are not accessible or feasible, HU therapy should be considered for secondary stroke prevention in children with SCD.

Evidence for a Novel Mechanism Independent of Myocardial Iron in β-Thalassemia Cardiac Pathogenesis

Human β-thalassemia major is one of the most prevalent genetic diseases characterized by decrease/absence of β-globin chain production with reduction of erythrocyte number. The main cause of death of treated β-thalassemia major patients with chronic blood transfusion is early cardiac complications that have been attributed to secondary iron overload despite optimal chelation. Herein, we investigated pathophysiological mechanisms of cardiovascular dysfunction in a severe murine model of β-thalassemia from 6 to 15-months of age in the absence of confounding effects related to transfusion. Our longitudinal echocardiography analysis showed that β-thalassemic mice first display a significant increase of cardiac output in response to limited oxygen-carrying erythrocytes that progressed rapidly to left ventricular hypertrophy and structural remodeling. Following this compensated hypertrophy, β-thalassemic mice developed age-dependent deterioration of left ventricular contractility and dysfunction that led toward decompensated heart failure. Consistently, murine β-thalassemic hearts histopathology revealed cardiac remodeling with increased interstitial fibrosis but virtual absence of myocardial iron deposits. Importantly, development of thalassemic cardiac hypertrophy and dysfunction independently of iron overload has uncoupled these cardiopathogenic processes. Altogether our study on β-thalassemia major hemoglobinopathy points to two successive phases resulting from severe chronic anemia and from secondarily induced mechanisms as pathophysiologic contributors to thalassemic cardiopathy.

Monocyte Chemotactic Protein-1 Is Associated with Microvascular Abnormalities and Serum Ferritin Concentrations in Sickle Cell Disease Patients

Abstract 3255 Introduction:Microvascular abnormalities underlie much of the morbidity observed in sickle cell disease (SCD). Adherence of sickle erythrocytes and leukocytes to the microvascular endothelium leads to vaso-occlusion and end organ ischemia/reperfusion injury. Monocyte chemotactic protein-1 (MCP-1) is a chemokine involved in the recruitment of monocytes to sites of endothelial activation or injury and thus contributes to the pathophysiology of vascular disease. In SCD patients, circulating MCP-1 concentrations are elevated during both steady state and vaso-occlusive crisis. However, the relationship between MCP-1 and microvascular abnormalities in SCD patients has not been assessed. In the present study, we measured a panel of circulating cytokines including serum MCP-1 and hematological biomarkers including serum ferritin in SCD patients who were being monitored by computer-assisted intravital microscopy (CAIM) to assess severity of microvasculopathy. Methods:The study included 31 steady state SCD patients (22 females, 9 males) ranging in age from 4–61 years. MCP-1 concentrations were measured by Luminex multiple analyte profiling. Ferritin concentrations were measured by chemiluminometric immunossay. The conjunctival microvasculature was assessed using CAIM. A severity index on a scale of 0–15 was calculated as described previously (Cheung et al, Am J Hematol 85:899, 2010) to quantify the degree of microvasculopathy observed among the patients. Results:The mean ± SD MCP-1 concentration was 445 ± 253 pg/ml (range: 122–1180 pg/ml), mean ± SD ferritin concentration was 1675 ± 1883 ng/ml (range 18–5825 ng/ml), and mean ± SD severity index was 5.0 ± 2.5 (range: 0–9). By multiple regression analysis, with controlling for age and gender, MCP-1 was directly correlated with severity index (p = 0.046), and serum ferritin was directly correlated with MCP-1 (p = 0.019). Conclusions:Monocyte recruitment to the site of endothelial injury involves chemotactic signaling mediated in part by MCP-1, levels of which rise in SCD. Our results indicate that MCP-1 is associated with and may directly contribute to the microvasculopathy observed in SCD patients. Furthermore, we find that MCP-1 levels are correlated with ferritin concentrations. Ferritin reflects body iron stores, and an increase of iron stores in SCD resulting from chronic blood transfusion as well as increased iron absorption associated with hemolysis may thus lead to monocyte/macrophage recruitment to the vascular endothelium and contribute to vasculopathy. Measurements of MCP-1 and ferritin may also serve as surrogate biomarkers of microvasculopathy severity and inflammation. Disclosures:Green:Emisphere - Consultancy : Consultancy; Teva Pharmaceuticals - expert testimony: Consultancy.

Impact of Jaundice On Adults with Sickle Cell Anemia

AbstractAbstract 4753 IntroductionFor many patients with sickle cell anemia (SCA), jaundice, yellow discoloration of the skin and mucous membranes, may be the most visible manifestation of their disease. The degree to which jaundice impacts the daily lives of patients with SCA has not been previously described. This study aims to assess the effect of jaundice on the health-related quality of life (HRQOL) of adults living with SCA. MethodsThis study was a cross-sectional survey of patients with SCA. A convenience sample of patients age > 17 years with SCA were approached during routine clinic visits to Parkland Memorial Hospital or UT Southwestern University Hospitals. Consenting patients completed a 15 question survey instrument. The survey was divided into three subscales (personal, relational, and behavioral) where individual items were presented in a 5-point Likert scale. This instrument was reviewed by non-study hematologists, nurses and patients for face validity. No other assessment of reliability or validity was performed. Additional data collected included serum total bilirubin (TB), hemoglobin, reticulocyte count (%) and patient self-report of current treatment for SCA (hydroxyurea [HU], chronic blood transfusions, or other).We tested for associations between survey subscales and TB, reticulocyte count, or hemoglobin using Spearman correlation coefficients. We compared the Spearman correlations of the survey subscales and TB between treatment and non-treatment groups using the Fisher's z transformation. Gender and age adjustments were made using linear regression. TB was transformed by natural log for regression analysis. ResultsWe surveyed 100 subjects (58% female) with SCA. The median age was 25 years (range: 18–63), and the median TB was 2.5 mg/dL (range: 0.4–13.8). Nearly half of patients reported receiving treatment with 28% on HU and 14% on chronic transfusions. The majority of patients reported a history of jaundice, with 79% listing responses of ‘sometimes', ‘often', or ‘always'. Summary results for the remainder of the survey are listed in the table.TB was positively correlated with the 3 subscales (personal, r=0.32, p=0.002; relational, r=0.38, p=0.0002; behavioral, r=0.31, p=0.003). We compared these correlations between ‘treatment' and ‘no treatment' groups and observed strong correlations in the ‘no treatment' group (personal, r=0.55, p<0.0001; relational, r=0.63, p<0.0001; behavioral, r=0.52, p=0.0002). TB was not correlated with the subscales in the ‘treatment' group. After adjusting for age, gender, and disease-modifying therapy, the three subscales were associated with TB (personal, β = 0.066, 95% Confidence Interval (CI) [0.027, 0.104], p=0.001; relational, β = 0.061, 95% CI [0.031, 0.092], p=0.0001; behavioral, β = 0.104, 95% CI [0.045, 0.164], p=0.0009). ConclusionJaundice negatively impacts the lives of many adults with SCA. The personal and relational subscales suggest more impact on the self-image of respondents, but only a few reported behavioral changes. The impact of jaundice appears to be mitigated by disease-modifying therapy for SCA (HU or chronic transfusions); however, this study was not created to determine the effectiveness of these reported treatments. Despite the fact this instrument was not validated, our study results suggest jaundice should be well-represented in HRQOL assessment tools in adults with SCA. Moreover, prospective studies are needed to clarify potential benefits of disease-modifying therapies, particularly HU, on the burden of jaundice in SCA.Table -Jaundice SurveySubscalesItemsResponses (Expressed as %)NeverAlmost NeverSometimesOftenAlmost AlwaysPersonalBothered by jaundice (N=93)4813171111Embarrassed by jaundice (N=92)5514111010Worry about jaundice (N=93)491515138RelationalTeased about jaundice (N=92)561215115Jaundice mentioned by others (N=89)1616272616Uncomfortable being asked about jaundice (N=93)5311141112Talked to others about jaundice (N=92)45232094Didn't fit in with friends because of jaundice (N=93)7413524BehavioralKept me from going to work, school, etc… (N=93)854920Try to avoid new people and places because of jaundice (N=93)7251094I tried to hide or cover-up my jaundice (N=93)7251094 Disclosures:Buchanan:HemaQuest Pharmacuetical, Inc.: Research Funding.

Examination of Risk and Resiliency in a Pediatric Sickle Cell Disease Population Using the Psychosocial Assessment Tool 2.0

To evaluate the Psychosocial Assessment Tool 2.0 (PAT) as an appropriate screening measure of risk for patient and family psychological distress in pediatric sickle cell disease (SCD). 219 caregivers completed the PAT during regular hematology clinic visits. Confirmatory factor analysis and tests of reliability were conducted. Multilevel modeling examined change and predictors of risk scores across four assessments. Confirmatory factor analysis factor loadings ranged from .03 to .81, and reliability coefficients ranged from .43 to .83. Risk for patient and sibling emotional problems, family problems, and parent stress reaction decreased over time. Increased patient age, chronic blood transfusion, lower caregiver education, caregivers being divorced, fewer adults and more children in the home, and greater financial difficulties were independent predictors of psychosocial risk. Results suggest that the PAT has utility in a pediatric sickle cell disease sample. Most caregivers reported low distress and high resiliency factors in this population.

An update on iron chelation therapy.

Iron overload is a common clinical problem, arising from disorders of increased iron absorption such as hereditary haemochromatosis or thalassaemia intermedia syndromes or as a consequence of chronic blood transfusions for various blood disorders. Regular red blood cell (RBC) transfusions are the principal supportive therapy for many rare anaemias involving a decrease in RBC production, an increase in cell destruction, or chronic blood loss1. Anaemias such as beta-thalassaemia and sickle cell disease are examples of chronic diseases that require long-term transfusion therapy to improve life expectancy. Although transfusion requirements may vary according to the diagnosis, chronic blood transfusion therapy inevitably leads to secondary iron overload that can cause significant damage to many organs, such as the liver and heart, and to the endocrine system2,3. Iron overload is associated with the production of free radicals that can damage tissues, resulting in cardiac toxicity, endocrine dysfunction, and liver toxicity. The effects of iron overload are visible after damage has been done, when patients already have liver dysfunction, cirrhosis, cardiomyopathy or diabetes1,4. Iron is an essential element within the body and its quantity is tightly regulated physiologically; however, the body has no mechanism to excrete excess iron and it deposits iron into end organs leading to severe dysfunction. Each unit of RBC transfused contains 180 to 200 mg of iron. Chronic packed RBC transfusion therapy increases liver iron by approximately 1 mg/mL (by dry weight) for every 15 mL/kg delivered5. Labile plasma iron (LPI) is a toxic and chelatable form of iron that is produced continually during conditions of iron overload, and has been linked to the development of co-morbidities6. It is very important to remove excess iron and suppress LPI to avoid the serious clinical sequelae associated with iron overload. In this specific context phlebotomy cannot be used because patients are usually anaemic and other means must be used to mobilise the excess iron. The gold standard is iron chelation therapy.

Ascorbate status modulates reticuloendothelial iron stores and response to deferasirox iron chelation in ascorbate-deficient rats

Iron chelation is essential to patients on chronic blood transfusions to prevent toxicity from iron overload and remove excess iron. Deferasirox (DFX) is the most commonly used iron chelator in the United States; however, some patients are relatively refractory to DFX therapy. We postulated that vitamin C supplementation would improve the availability of transfusional iron to DFX treatment by promoting iron's redox cycling, increasing its soluble ferrous form and promoting its release from reticuloendothelial cells. Osteogenic dystrophy rats (n = 54) were given iron dextran injections for 10 weeks. Cardiac and liver iron levels were measured after iron loading (n = 18), 12 weeks of sham chelation (n = 18), and 12 weeks of DFX chelation (n = 18) at 75 mg/kg/day. Ascorbate supplementation of 150 ppm, 900 ppm, and 2250 ppm was used in the chow to mimic a broad range of ascorbate status; plasma ascorbate levels were 5.4 ± 1.9, 8.2 ± 1.4, 23.6 ± 9.8 μM, respectively (p < 0.0001). The most severe ascorbate deficiency produced reticuloenthelial retention, lowering total hepatic iron by 29% at the end of iron loading (p < 0.05) and limiting iron redistribution from cardiac and hepatic macrophages during 12 weeks of sham chelation. Most importantly, ascorbate supplementation at 2250 ppm improved DFX efficiency, allowing DFX to remove 21% more hepatic iron than ascorbate supplementation with 900 ppm or 150 ppm (p < 0.05). We conclude that vitamin C status modulates the release of iron from the reticuloendothelial system and correlates positively with DFX chelation efficiency. Our findings suggest that ascorbate status should be probed in patients with unsatisfactory response to DFX.

Transfusion Transmitted Infections in Indian Thalassemics: A Perspective

To the Editor, We read with interest the paper entitled “Blood transfusion transmitted infections in multiple blood transfused patients of beta thalassemia” by Vidja et al. [1] in your esteemed journal. Patients with thalassemia major require chronic blood transfusion and thus they are at serious risk of transfusion transmitted viral infections. There are several studies on prevalence of transfusion transmitted infections (TTI) in thalassemics from this country [2–5]. To put in proper perspectives these studies can be classified into three groups. (i) Those conducted prior to or within 2–3 years of Supreme Court order for mandatory testing for HIV. (ii) Those published between 1995 and 2002 when mandatory testing for HCV by serological technique that was not in force but HIV testing was a must. (iii) Post 2002 when serological screening of all three viruses i.e. HIV, hepatitis B and C were under taken in multitransfused thalassemic patients. Studies conducted in and around 1988 showed extremely high prevalence of HIV infection in the range of 14–18 % among multitransfused thalassemic patients [2, 3] while prevalence of hepatitis B and C virus infection remained at 14 and 25–38 %, respectively [4, 5]. Post 2002 studies [1, 6, 7] including the present one show interesting data. In the present study (1), the TTI in multitransfused thalassemics have been reduced substantially almost to the level of their prevalence in normal population. However, a similar study conducted from the same state [6] showed extremely high prevalence of hepatitis C infection. This high prevalence of hepatitis C infection is in line with similar contemporary study [7]. Hemophilia in India is still managed with liquid blood products like whole blood, FFP and cryoprecipitate. A study conducted by Ghosh et al. [8] showed high prevalence of hepatitis B and C infections in these patients. Today hepatitis B vaccine is available and it is very effective. Hence all patients who are likely to require multiple transfusions should always be vaccinated. NAT testing is widely recommended to reduce further the transfusion transmitted viral infections. One such study published from this country [9] has shown that blood units seronegative for HIV 1+2, HbsAg and hepatitis C has 1:1,000–1:1,500 NAT positivity rate (infective units) and majority of the positivity (80 %) is due to hepatitis B virus underlining the urgent need of hepatitis B vaccination for all likely multitransfused thalassemic patients. Variation in prevalence of TTI amongst multitransfused thalassemics even after serological screening could be related to geographical differences in prevalence of the viral infections amongst blood donors, nature of blood donors and nature of care the thalassemia patients are receiving. In centres where thalassemia patients are better cared for may show higher prevalence of these viral infections even if all other factors are constant simply because better cared thalassemics live longer and are exposed to more blood units hence more chances of TTI. Hence while describing prevalence of contracting TTI some normalization is required in terms of mean blood units transfused to patients so that the data becomes comparable.

HIV Infection in Infants and Children - An Updated Review

DOI: http://dx.doi.org/10.3329/bjch.v34i2.10219 BJCH2010; 34(2): 62-66

Shire Bolsters its Haematology Business with US$325 M FerroKin BioSciences Acquisition

Shire has moved to strengthen its haematology franchise by agreeing to acquire FerroKin BioSciences for up to US$325 M. With the acquisition, Shire will gain FerroKin’s iron chelator FBS0701, which is in Phase II development for the treatment of iron overload due to chronic blood transfusions. Shire will pay US$100 M upfront in cash and up to US$225 M in potential clinical development, regulatory and commercial milestones related to the drug, which could be launched as early as 2016.

Silent Cerebral Infarcts in Children With Sickle Cell Anemia

Source: Debaun MR, Sarnaik SA, Rodeghier MJ, et al. Associated risk factors for silent cerebral infarcts in sickle cell anemia: low baseline hemoglobin and relative high systolic blood pressure. Blood. Epub 2011 Nov 17; doi: 10.1182/blood-2011-05-349621Investigators from 29 clinical sites in the United States conducted the Silent Cerebral Infarct Transfusion (SIT) Trial to assess the risk factors for silent cerebral infarcts (SCI). In this cross-sectional study, children with sickle cell anemia (SCA) between the ages of 5 and 15 years with no history of overt stroke or seizures were evaluated with magnetic resonance imaging (MRI) of the brain to screen for SCI. SCI was radiographically defined as MRI signal abnormality measuring at least 3 mm on the T-2 weighted images judged by two of three neuroradiologists on a central review committee. SCI was determined to be truly silent by a central neurology committee’s review of the local neurologist’s examination and the patient’s MRI findings. Clinical history and baseline laboratory values were examined to determine potential risk factors for SCI.Study data were analyzed on 814 participants; the mean age of enrolled children was 9.1 years and 50.7% were male. SCIs were diagnosed in 30.8% (n=251) of study patients. In a multivariable logistic regression analysis, lower baseline hemoglobin concentration (P<.001), higher baseline systolic blood pressure (SBP) (P=.013), and male gender (P=.026) were all associated with a significantly increased risk of a SCI. The odds ratio for SCIs for patients with a hemoglobin less than 7.6 g/dl or SBP greater than 112 mm/Hg were 2.12 and 1.73, respectively. Those individuals who had both a hemoglobin less than 7.6 and SBP greater than 104 had the highest odds of a SCI. In addition, 83% (5 of 6) of patients who carried a diagnosis of hypertension had a higher rate of SCIs than the other study participants (P=.012).The investigators conclude that lower hemoglobin concentration and higher SBP are risk factors for SCI in children with SCA. Further research is needed to determine if interventions targeting these risk factors, such as hydroxyurea, blood transfusion therapy, or antihypertensive medications, can be effective in preventing SCIs.Dr Villella has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.Although previous investigators have also identified SCIs in approximately one third of patients with SCA, this study is the first to identify a lower baseline hemoglobin and higher SBP as risk factors for SCI in a large multicenter setting.1–3 SCIs may be silent, but they are not benign. SCIs in children with SCA are associated with an increased risk of overt stroke as well as progressive SCIs.4 Additionally, SCIs are associated with poorer cognitive function and school performance as compared to children with SCA without SCIs as well as sibling controls.5–6 Even more concerning is the finding that cognitive function appears to worsen over time in children with SCA and SCIs.7 As children mature and develop into young adults, they may be silently losing IQ points. Indeed, a recent study showed that asymptomatic adults with SCA have significantly lower performance IQs as compared to matched controls.8These findings have important implications for all pediatric practitioners. Many children do not live in close proximity to a sickle cell center and therefore the responsibility of providing health maintenance for these children can fall onto the shoulders of the primary care giver. The American Academy of Pediatrics recommends that all children with SCA receive a thorough assessment of school attendance and performance with consideration for formal neurocognitive testing.9 MRI of the brain should also be considered for children struggling in school, although this remains controversial since a proven intervention to prevent or limit SCIs is lacking. Neurocognitive testing, however, can be extremely helpful in identifying cognitive deficiencies and helping the family and school to optimize the child’s learning environment.There is strong evidence that SCIs in children with SCA are common and associated with significant morbidity. Studies evaluating potential interventions are desperately needed. By identifying risk factors for SCI in this study, the investigators have uncovered potential therapeutic targets which may respond to interventions to decrease the proportion of sickle cells and thereby increase cerebral blood flow, such as hydroxyurea and chronic blood transfusion therapy, or decrease blood pressure through the use of antihypertensive medications. Thankfully, the investigators of the SIT trial are addressing this as well. Patients enrolled into SIT are randomized to receive chronic blood transfusion therapy or standard observation. Follow-up imaging and neurocognitive testing is then performed to ascertain whether chronic blood transfusion therapy can prevent progression of SCIs and stabilize cognitive function. We anxiously await the results.

Abstract 2602: Changing Ethnic Disparity in Ischemic Stroke Mortality in US Children after the STOP Trial

Objective: A prior report showed higher stroke mortality in U.S. black children compared to white children (1979-1998), a disparity likely due in part to sickle cell disease. We hypothesized that this disparity has diminished since the publication of the Stroke Prevention Trial in Sickle Cell Anemia (STOP) trial in 1998 demonstrating the efficacy of chronic blood transfusions for primary stroke prevention. Because most childhood strokes in the setting of sickle cell disease are ischemic, we would expect a greater impact on ethnic disparities in ischemic than hemorrhagic stroke. Methods: We evaluated the demographics and secular trends in mortality from ischemic and hemorrhagic stroke in U.S. children &lt;20 years of age, using death certificate data from the National Center of Health Statistics (NCHS) from 1988 to 2007. Results: A total of 1,555,045,537 person-years were included in the study. There were 4,425 deaths attributed to childhood stroke (as primary cause of death) within this cohort, yielding an average of 221 deaths per year. Ischemic strokes accounted for 20% of deaths; hemorrhagic strokes accounted for 67% (12% were unspecified). The relative risk of ischemic stroke mortality for black versus white children from 1988 to 1998 was 1.74 (95% CI 1.42-2.13, p&lt;0.001) while the relative risk from 1999 to 2007 was 1.27 (95%CI 0.99-1.64, p= 0.063). While ischemic stroke mortality rates in black versus white children appear to be converging, the ethnic disparity in hemorrhagic stroke mortality has remained relatively stable ( Figure 1 ). Conclusion: The excess risk of death from ischemic, but not hemorrhagic, stroke in U.S. black children has decreased over the past decade. This may be related to the implementation of an effective primary stroke prevention strategy for children with sickle cell disease.

Torque teno virus and hepatitis C virus co-infection in Iranian pediatric thalassemia patients.

Objective: Torque teno virus (TTV) infects patients at risk for parenteral exposure and chronic blood transfusion, such as those with β-thalassemic. This study aimed to assess the prevalence of TTV infection and co-infection of TTV and hepatitis C virus (HCV) in pediatric thalassemia patients receiving chronic blood transfusion. Material and Methods: The study included 90 pediatric thalassemia patients receiving chronic blood transfusion that presented to the Mofid Children’s Hospital, Tehran, Iran. The control group included 90 healthy volunteer children. Serum TTV DNA detection via semi-nested PCR and HCV Ab were performed in all the participants. Demographic characteristics and clinical data were collected from each participant for statistical analysis. Results: In all, 64.4% of the patients had TTV infection, versus 24.4% of the controls (P < 0.01). The thalassemia patients had a greater probability of having TTV and HCV infections than the controls, with a common OR of 5.60 (95% CI: 2.94-10.69) and 2.15 (95% CI: 1.83-2.50), respectively. In total, 17.2% (10/58) of the patients that were TTV positive were also HCV positive, whereas 6.3% (2/32) of the TTV-negative patients were anti-HCV antibody (Ab) positive (P = 0.14).Conclusion: The prevalence of TTV and HCV infection was higher in the Iranian thalassemia patients on chronic transfusion therapy than in the controls. The high prevalence of TTV in pediatric thalassemia patients on chromic transfusion therapy may indicate the superiority of the parenteral route compared to other routs of TTV transmission.

A study of the prevalence of thalassemia and its correlation with liver function test in different age and sex group in the Chittagong district of Bangladesh.

Thalassemia is the name of a group of genetic, inherited disorders of the blood. More specifically, it is a disorder of the hemoglobin molecule inside the red blood cells. According to World health Organization (WHO), there are about 3% beta-thalassemia carrier and about 4% Hb E/beta-thalassemia carrier in Bangladesh. Our objective is to identify the prevalence of beta-thalassemia in our adolescent populations and to review risk factors that would most easily identify a subset of adolescent patients at greatest risk for the development of beta-thalassemia. We also made a study of clinical profile of 53 thalassemic patients, observing the relationship between the patients with their verity ages and sex. The cases are taken on the basis of their age (2-30 years), beta-thalassemia major, clinical jaundice with history of chronic blood transfusion. The cases excluded those who had jaundice due to viral hepatitis or hepatitis due to heavy metal poisoning (Arsenic) and those with spleenectomy. Liver function test has been evaluated in 53 patients. That were recorded with some relevant demographical data such as age, sex, blood group where median age was of 16 years and mean (±SD) age 15.4151 ± 7.90918. Among them were 21 (39.6%) female and 32 (60.4%) male. With an average 15.1% (8 in no.) beta-thalassemia, 7.5% (4 in no.) beta-thalassemia major and 77.4% (41 in no.) E-beta-thalassemia cases have been found in the study. Mean (±SD) TSB in total 53 subjects with age group 2-10 years and 21-30 years is significant. The study revealed that in thalassemic patients when the age is more, the disease progresses with their complication. Hepatic complication is mainly due to being hepatocellular in nature than that of obstructive one.

Beliefs about chelation among thalassemia patients

BackgroundUnderstanding patients’ views about medication is crucial to maximize adherence. Thalassemia is a congenital blood disorder requiring chronic blood transfusions and daily iron chelation therapy.MethodsThe Beliefs in Medicine Questionnaire (BMQ) was used to assess beliefs in chelation in thalassemia patients from North America and London in the Thalassemia Longitudinal Cohort (TLC) of the Thalassemia Clinical Research Network (TCRN). Chelation adherence was based on patient report of doses administered out of those prescribed in the last four weeks.ResultsOf 371 patients (ages 5-58y, mean 24y), 93% were transfused and 92% receiving chelation (26% deferoxamine (DFO; a slow subcutaneous infusion via portable pump), 63% oral, 11% combination). Patients expressed high “necessity” for transfusion (96%), DFO chelation (92%) and oral chelation (89%), with lower “concern” about treatment (48%, 39%, 19% respectively). Concern about oral chelation was significantly lower than that of DFO (p<0.001). Self-reported adherence to chelation was not associated with views about necessity or concerns, but negatively correlated with perceived sensitivity to DFO (Sensitive Soma scale; r=−0.23, p=0.01) and side effects of oral chelation (r=−0.14, p=0.04). High ferritin iron levels, potentially indicating lower adherence, were found in 41% of patients reporting low necessity of oral chelation compared to 24% reporting high necessity (p=0.048). Concerns about treatment were associated with lower quality of life and more symptoms of anxiety and depression.ConclusionsDespite their requirement for multimodal therapy, thalassemia patients have positive views about medicine, more so than in other disease populations. Patients may benefit from education about the tolerability of chelation and strategies to effectively cope with side effects, both of which might be beneficial in lowering body iron burden.Clinicaltrials.gov identifierNCT00661804

More definitions in sickle cell disease: Steady state v base line data

Ballas et al. [1] published concise definitions of the complications of sickle cell disease (SCD). There are other definitions that pertain to SCD that are not complications of the disease as such but are associated with establishing the accurate diagnosis, management, and natural history of each complication. Definition of the steady state and of baseline clinical features and lab data are two such examples. These are important in detecting any significant acute change in the clinical picture or any change after the initiation of therapeutic modalities. No history of an acute painful episode that required treatment in the emergency department or in the hospital for at least four consecutive weeks after a previous painful crisis. No history of admission to the hospital or emergency department 2–3 days after the point in time in question. Previous studies showed that the number of irreversibly sickled cells increases and RBC deformability decreases 2–3 days before admission to the hospital in crisis [2]. This change coincides with the prodromal phase of the acute painful crisis described in children and adults [3, 4]. No history of blood transfusion during the previous 4 months of the point in time. Alternately, the % of Hb A determined by electrophoresis or by high performance liquid chromatography must be ≤10%. The exception would be in patients with sickle-β+-thalassemia in whom endogenous Hb A could be as high as 30%. In these patients, history of recent blood transfusion could be obtained from the blood bank that usually supports the institution in question. Patients on chronic blood transfusion or exchange transfusion may be exempt from this requirement or their Hb S steady state level could be the average of 3 determinations of the % of Hb S before scheduled transfusion or exchange transfusion. No history of intercurrent illness such as infection, inflammation during the previous 4 weeks. No treatment with medications such as antibiotics that may affect the blood counts during the previous 3 weeks. The steady state values may change with time. It is, therefore, advisable to determine them periodically every 2–3 years. Knowing the steady state values is extremely important in evaluating patients who present themselves with acute episodes. Comparing data during the acute event with the steady state values often reveals objective changes during crisis. Baseline values include clinical and lab data determined before the initiation of therapy or other interventions. They do not need to meet the requirement of steady state values. Occasionally, they could be the same as steady-state values especially in patients who have relatively mild disease with infrequent painful episodes. Baseline values are markers of the effect of an intended intervention whereas steady-state values are markers of the disease itself. Samir K. Ballas*, * Department of Medicine Cardeza Foundation for Hematologic Research Jefferson Medical College Philadelphia, Pennsylvania.

Health Care Utilization for Painful Events Is Associated with Early Mortality in a Contemporary Population of Adults with Sickle Cell Anemia

Abstract▪2115▪This icon denotes a clinically relevant abstract Background:Painful vaso-occlusive crises are the most common symptom associated with sickle cell anemia (SCA) and show a large inter-patient variability in the frequency and severity. Historically a high rate of admissions for pain is associated with early mortality in SCA adults. Modern day management of SCA includes screening for life threatening complications such as pulmonary hypertension and disease modifying therapies such as hydroxyurea and chronic blood transfusions. It has also become clear that all acute painful events including some self reported crisis do not lead to ED visit/ hospitalization therefore use of healthcare utilization may underestimate the actual frequency of painful vaso-occlusive crises. The present study determined if ED visit/ hospitalizations for painful vaso-occlusive crises remain a marker of early mortality in the modern era. Methods:To determine the relative contribution of pain and other established risk factors for death in a contemporary adult cohort with sickle cell anemia, we analyzed data of SCA individuals who were evaluated at NIH between February 2001 and June 2007 for screening of the IRB approved protocol to study pulmonary hypertension in sickle cell disease. Self reported history of vaso-occlusive painful events requiring visit to an emergency department (ED) or in-patient hospitalization in 12 months preceding the enrollment was used to stratify study subjects into no-ED visit/ hospitalization or ED visit/hospitalization group. Characteristics between the groups were compared. Doppler echocardiography was used to estimate systolic pulmonary artery pressure through measurement of the tricuspid regurgitation velocity (TRV). Study subjects were followed prospectively and age at death was recorded. Results:One hundred and four (40%) SCA subjects reported no ED visit/ hospitalization while 160 (60%) reported at least one ED visit/ hospitalization in 12 months preceding the enrollment. Although not statistically significant, a higher proportion of study participants in the ED visit/ hospitalization group were on hydroxyurea (38 vs. 69%; P=0.4), and more likely to have received > 10 red cell transfusions (37 vs. 48%; P= 0.09). The no-ED/ hospitalization group and ED/ hospitalization groups were not different in median age (33 vs. 31; P=0.1) or fetal hemoglobin concentration (7.7 vs. 6.9%; P=0.3). Overall forty (15.1%) individuals died during the median follow-up period of 5 years. Cox proportional hazards analysis was performed to determine if severe pain crisis requiring ED visits/hospitalizations were associated with early mortality after adjusting for other known risk factors for mortality (Table 1). Risk for mortality was significantly associated with a history of severe pain crisis requiring ED visit/hospitalization in preceding year (RR 2.81, 95% CI: 1.2–6.4, P= 0.04), elevated TRV ≥ 3 m/s (RR 4.07, 95% CI: 1.3–12.8, P= 0.02) and elevated ferritin (RR 2.31, 95% CI: 1.0–5.0, P= 0.04).Table 1:Cox Proportional Hazards Analysis of MortalityRisk FactorsRR (95% CI)1P2ED visits/hospitalization in past year2.81 (1.2–6.4)0.04TRV, m/sec2.5–2.92.46 (0.8–7.9)0.133.0+4.07 (1.3–12.8)0.02Ferritin2.31 (1.0–5.2)0.041 RR for TRV is given relative to <2.5 m/sec; RR for ED is given relative to zero visits in the past year. RR for ferritin is given for the 75th relative to the 25th percentile.2From Wald χ2 Conclusions:Severe painful episodes requiring health care utilization are associated with premature mortality and despite likely underestimation of actual frequency of pain, remain a marker of disease severity. Elevated TRV a marker of elevated pulmonary arterial pressure and early mortality has a cumulative effect with pain on reduced survival. Consistent with Cooperative Study of Sickle Cell Disease (CSSCD) report, higher hemoglobin (and lower LDH) was associated with reports of ED visit/ hospitalization likely related to increased viscosity. We conclude that as a group, SCA patients reporting severe pain requiring ED visits /hospitalization and elevated TRV are at the highest risk for shortened survival. Disclosures:No relevant conflicts of interest to declare.

Hybrid AAV6/2-Mediated Human β-Globin Expression in β-Thalassemia Patient Hematopoietic Stem Cells Transplanted Into Irradiated BALB/c Nude Mouse

Abstract 4715β -Thalassemia is one of the most common worldwide monogenic human diseases,caused by molecular defects in the human β -globin gene cluster leading to decrease or absence of β-globin. Loss of β -globin chains causes ineffective production of oxygen-carrying hemoglobin and therefore results in severe anemia. The treatment for β -Thalassemia major usually includes lifelong blood transfusions but chronic blood transfusion often causes iron overload, and accumulated iron produces tissue damage in multiple organs, so that iron chelating treatment is also needed. Bone marrow transplantation is another effective therapy, which can eliminate a patient’s dependence on blood transfusions, however, it is difficult to find a matching donor for most patients; therefore it is only available for a minority of patients.Gene therapy is one potential novel therapy for treatment of inherited monogenic disorders. The long–term therapeutic strategy for this disease is to replace the defective β-globin gene via introduction of a functional gene into hematopoietic stem cells (HSCs). Adeno-associated virus type 2 (AAV), a nonpathogenic human parvovirus, has gained attention as a potentially useful vector for human gene therapy. AAV can infect both dividing and non-dividing cells and wild AAV integrates preferentially at a specific site on human chromosome 19. In the absence of helper virus, recombinant AAV will stably integrate into the host cell genome, mediating long-term and stable expression of the transgene.In this study, we used a hybrid rAAV6/2 vector carrying the human β-globin gene to transduce HSCs from a β -Thalassemia patient, followed by transplantation into irradiated BALB/c nude mice. One month post-transplantation, Hb was prepared from peripheral blood and analyzed by Western Blot and HPLC respectively. RNA and DNA were isolated from bone marrow cells (BMCs) from recipient mice transplanted with mock-infected or hybrid rAAV–globin-infected cells and analyzed by RT-PCR and PCR respectively. The results showed: 1. Human β-actin and β-globin transcripts were detected by RT-PCR in BMCs from all recipient mice, indicating that human HSCs were successfully transplanted in these mice and that the human β-globin gene was transcriptionally active in the donor cells. 2. The level of human hemoglobin expressed in peripheral red blood cells of recipient mice as measured by HPLC (ratio of β/α) was increased to 0.3 from 0.05 of pre-transplantation levels. Expression of human β-globin was also confirmed in recipient mice by Western Blot; a 2–3-fold increase compared with that of controls.Our results indicate that human HSCs from a β-Thalassemia patient can be efficiently transduced by a hybrid rAAV6/2-β-globin vector followed by expression of normal human β-globin protein. This study provides a proof-of-concept that rAAV6/2-mediated gene transfer into human HSCs might be a potential approach for gene therapy of β-Thalassemia. Disclosures:No relevant conflicts of interest to declare.