Thalassemias

Comparison of screening indicators for different types of thalassemia carriers in Hunan Province

Background

Carrier screening is the most effective method to block the occurrence of thalassemia. However, due to differences in race and genotype, MCV, MCH, HbA2 and other indicators are far from each other. The purpose of this study is to evaluate the common screening indicators of a, b and ab-compound thalassemia carriers in Hunan Province, and try to use the relevant formulas in the existing literature to predict and distinguish different types of thalassemia carriers.

Methods

Receiver operating characteristic curve (ROC curve) combined with Youden index was utilized to analyze results of blood routine examination, hemoglobin electrophoresis, and literature-related formulas for 1111 a-thalassemia carriers, 464 b-thalassemia carriers and 24 ab-thalassemia carriers.

Kidney transplantation in an adult with transfusion-dependent beta thalassemia: A challenging case report and literature review

The markedly increased survival of transfusion-dependent beta thalassemia patients has led to the recognition of new complications, such as renal disorders. Kidney transplantation is nowadays the preferred treatment option for end-stage kidney disease (ESKD). We describe a case of a 49-year-old woman with β-Transfusion Dependent Thalassemia, who developed ESKD as a result of focal segmental glomerulosclerosis and received a deceased-donor kidney transplant following hemodialysis for over a decade. The particular challenges of this case are discussed, including the long-term survival in hemodialysis. Our patient had to overcome multiple obstacles, including hypercoagulability issues presented in the form of thromboembolism, infections, such as hepatitis C and gastroenteritis, and the acute T-cell-mediated rejection, which had to be managed postoperatively. A review of the current literature revealed only one previous report of a thalassemia patient who successfully underwent renal transplantation. More than a year after the transplantation our patient presents with a normal glomerular filtration rate (GFR=62ml/min/1.73m²) and creatinine level (Cr=0.96mg/dL) and is transfused every 3 weeks. In conclusion, renal transplantation is possible in patients with TDT and should not be discouraged. Regular transfusions and optimal follow-up for the elimination of post-transplant complications are required.

Feasibility of combining short tandem repeats (STRs) haplotyping with preimplantation genetic diagnosis (PGD) in screening for beta thalassemia

β-thalassemia is an autosomal recessive disease with the reduction or absence in the production of β-globin chain in the hemoglobin, which is caused by mutations in the Hemoglobin subunit beta (HBB) gene. In Vietnam, the number of β-thalassemia carriers range from 1.5 to 25.0%, depending on ethnic and geographical areas, which is much higher than WHO's data worldwide (1.5%). Hence, preimplantation genetic diagnosis (PGD) plays a crucial role in reducing the rate of β-thalassemia affected patients/carriers. In this research, we report the feasibility and reliability of conducting PGD in combination with the use of short tandem repeat (STR) markers in facilitating the birth of healthy children. Six STRs, which were reported to closely linked with the HBB gene, were used on 15 couples of β-thalassemia carriers. With 231 embryos, 168 blastocysts were formed (formation rate of 72.73%), and 88 were biopsied and examined with STRs haplotyping and pedigree analysis. Thus, the results were verified by Sanger sequencing, as a definitive diagnosis. Consequently, 11 over 15 couples have achieved pregnancy of healthy or at least asymptomatic offspring. Only three couples failed to detect any signs of pregnancy such as increased Human Chorionic Gonadotropin (HCG) level, foetal sac, or heart; and one couple has not reached embryo transfer as they were proposed to continue with HLA-matching to screen for a potential umbilical cord blood donor sibling. Thus, these results have indicated that the combination of PGD with STRs analysis confirmed by Sanger sequencing has demonstrated to be a well-grounded and practical clinical strategy to improve the detection of β-thalassemia in the pregnancies of couples at-risk before embryo transfer, thus reducing β-thalassemia rate in the population.

Amlodipine: Can act as an antioxidant in patients with transfusion-dependent β-thalassemia? A double-blind, controlled, crossover trial

BACKGROUND AND AIM

This study aimed to assess the antioxidant effects of amlodipine in transfusion-dependent β-thalassemia (TDT) patients.

METHODS

This crossover trial consisted of two sequences (AP and PA). In the AP sequence, nine cases received amlodipine 5 mg daily (phase I) and then were switched to placebo (phase II). In PA sequence, 10 patients took the placebo (phase I) and were shifted to amlodipine (phase II). The washout period was 2 weeks. The length of each phase was 6 months. Serum malondialdehyde (MDA, μmol/L), carbonyl (protein CO, μM/L), glutathione (GSH, nM/L), and total antioxidant capacity (TAC, μmol FeSO4/L) were measured in the beginning and at the end of phases I and II. The clinical significance was viewed as a minimum change difference of 5% for each outcome between amlodipine and placebo.

RESULTS

Seventeen cases completed the study. According to the baseline MDA values, the adjusted Hedges's g for MDA was -0.59, 95% confidence interval [CI] -1.26 to 0.08. After controlling the baseline protein CO values, Hedges's g computed for protein CO was -0.11, 95% CI -0.76 to 0.55. The estimated values of the adjusted Hedges's g for GSH and TAC were also 0.26, 95% CI -0.40 to 0.91, and 0.42, 95% CI -0.24 to 1.09, respectively. The change difference for MDA was 8.3% (protein CO 2.2%, GSH 3.1%, and TAC 12.9%).

CONCLUSION

Clinically, amlodipine therapy is an efficacious adjuvant treatment with conventional iron chelators for improving the levels of MDA and TAC in patients with TDT.

A novel rearrangement of the α-globin gene cluster containing both the -α3.7 and ααααanti4.2 crossover junctions in a Chinese family

BACKGROUND

Thalassemia is one of the most common hemoglobinopathies. Thalassemia is mainly caused by the loss and/or deficiency of one or more globin chains in hemoglobin. The copy number variant (CNV) of α-globin gene is one of the important factors affecting the clinical phenotype of β-thalassemia. The precise detection for this type of variation is needed.

METHODS

Peripheral blood of a 33-year-old man and his family members were collected. Complete blood counts and serum iron levels were measured for participants. Genomic DNA was extracted from all family members. Routine genetic analysis of thalassemia was performed to determine the genotype. Additional PCR-electrophoresis and Multiplex ligation dependent probe amplification (MLPA) were conducted. Single-molecule real-time technology(SMRT) was then performed as a validation assay and further characterization of the variant for family members.

RESULTS

PCR-electrophoresis and MLPA found a new variant, but the exact genotype could not be determined. At last, SMRT identified the new variant as a rearrangement of the α-globin gene cluster named αHKαα (NC_000016.9:g.169818_174075dup169818_174075dup173302_177105del), which contained both the -α3.7 and ααααanti4.2 crossover junctions. Carriers of the novel CNV show normal clinical phenotype according to the hematological results.

CONCLUSION

We have identified an unreported CNV (αHKαα) in α-globin gene cluster. The novel CNV not only demonstrates the accuracy and efficiency of our combining strategy in detecting unknown CNVs, but also enriched the variant spectrum of thalassemia.

Adherence to Iron Chelation Therapy among Adults with Thalassemia: A Systematic Review

Iron chelation therapy (ICT) is essential to prevent complications of iron overload in patients with transfusion-dependent thalassemia. However, the role that adherence to ICT plays in health-related outcomes is less well known. Our objectives were to identify adherence rates of ICT, and to assess methods of measurement, predictors of adherence, and adherence-related health outcomes in the literature published between 1980 and 2020. Of 543 articles, 43 met the inclusion criteria. Studies measured ICT adherence, predictors, and/or outcomes associated with adherence. Most studies were across multiple countries in Europe and North America (n = 8/43, 18.6%), recruited in clinics (n = 39/43, 90.7%), and focused on β-thalassemia (β-thal) (n = 25/43, 58.1%). Common methods of assessing ICT adherence included patient self-report (n = 24/43, 55.8%), pill count (n = 9/43, 20.9%), prescription refill history (n = 3/43, 7.0%), provider scoring (n = 3/43, 7.0%), and combinations of methods (n = 4/43, 9.3%). Studies reported adherence either in 'categories' with different levels of adherence (n = 24) or 'quantitatively' as a percentage of doses of medication taken out of those prescribed (n = 17). Adherence levels varied (median 91.7%, range 42.0-99.97%). Studies varied in sample size and methods of adherence assessment and reporting, which prohibited meta-analysis. Due to a lack of consensus on how adherence is defined, it is difficult to compare ICT adherence reporting. Further research is needed to establish guidelines for assessing adherence and identifying suboptimal adherence. Behavioral digital interventions have the potential to optimize ICT adherence and health outcomes.

Dynamic Thiol-Disulfide Homeostasis in Children With β-Thalassemia Trait

In children with β-thalassemia (β-thal) trait, tissue damage occurs with oxidative stress due to oxygen free radicals and reactive oxygen species (ROS) production. Dynamic thiol-disulfide homeostasis (DTDH) is one of the most important indicators showing the pro-oxidant/antioxidant status in the body. In this study, we aimed to examine the status of DTDH by measuring native thiol, disulfide, and total thiol levels in children with β-thal trait. The study included 40 children with β-thal trait and 30 healthy controls (matched by age and gender). The DTDH parameters were measured by an automated method and results were compared between the groups. The levels of native thiol, total thiol, and disulfide in children with β-thal trait group were statistically significantly higher than the control group (p < 0.001). There was no significant difference in disulfide/native thiol, disulfide/total thiol, and native thiol/total thiol levels between the groups. In addition, there was no correlation between hemoglobin (Hb) and serum ferritin levels with the markers of DTDH in children with β-thal trait. In our study, a significant increase was found in native thiol, total thiol, and disulfide levels in response to oxidative stress in children with β-thal trait compared to the healthy control group. Disulfide levels of the children with β-thal trait were higher than the control group, showing oxidative stress is high in β-thal trait. Accordingly, it increases the native thiol and total thiol capacity as compensation.

Use of Deferasirox Film-Coated Tablets in Pediatric Patients with Transfusion Dependent Thalassemia: A Single Center Experience

Thalassemic syndromes are characterized by clinical heterogenicity. For severe disease forms, lifelong blood transfusions remain the mainstay of therapy, while iron overload monitoring and adequate chelation treatment are required in order to ensure effective disease management. Compared to previous chelators, the new deferasirox film-coated tablet (DFX FCT) is considered to offer a more convenient and well-tolerated treatment scheme, aiming at better treatment-related and patient-related outcomes. The present study’s objective was to prospectively evaluate the safety and efficacy of DFX FCT in children and adolescents with transfusion-dependent thalassemia. Data collected included patient demographics, hematology and biochemistry laboratory work up, magnetic resonance imaging of heart and liver for iron load, as well as ophthalmological and audiological examination prior to and a year following drug administration. Study results confirmed DFX FCT safety in older children in a manner similar to adults, but demonstrated increased frequency of adverse events in younger patients, mainly, involving liver function. With regards to efficacy, study results confirmed the preventive role of DFX FCT in iron loading of liver and heart, however, higher doses than generally recommended were required in order to ensure adequate chelation.

Association between left ventricular strain and cardiac iron load in beta-thalassaemia major: a cardiac magnetic resonance study

OBJECTIVE

To evaluate the utility of cardiac magnetic resonance feature tracking-derived left ventricular strain in assessing cardiac dysfunction and investigate the correlation between left ventricular strain and myocardial T2* in patients with beta-thalassaemia major.

METHODS

Forty-two patients with beta-thalassaemia major, having a mean age of 22.49 ± 8.48 years, and age-matched healthy controls were enrolled in the study. The observer drew regions of interest on the interventricular septum, and T2* decay curves were calculated accordingly. The short-axis cine images were used to derive left ventricular circumferential and radial strains, and the long-axis four-chamber and two-chamber images were used to assess left ventricular longitudinal strain.

RESULTS

The mean global left ventricular strains were lower in beta-thalassaemia major patients than the controls (p < 0.05). Left ventricular strains of beta-thalassaemia major patients with cardiac T2* values of > 20 ms were also significantly reduced compared with the controls (p < 0.05); there was no difference between the mean left ventricular ejection fractions of the two groups (p = 0.84). Cardiac T2* showed a weak correlation with left ventricular ejection fraction (r = 0.33, p = 0.03), while the left ventricular circumferential strain showed a good positive correlation with cardiac T2* (r = 0.6, p < 0.0001).

CONCLUSION

Compared with healthy controls, patients with beta-thalassaemia major, including those with myocardial T2* values of >20 ms, showed reduced global left ventricular strains. Left ventricular circumferential strain was positively correlated with myocardial T2*. Left ventricular strain analysis using cardiac magnetic resonance feature tracking may have utility in beta-thalassaemia major assessment.Key FindingsPatients with beta-thalassaemia major, including those with myocardial T2* values of >20 ms, had reduced global left ventricular strains.Cardiac T2* showed a weak correlation with left ventricular ejection fraction, while the left ventricular circumferential strain showed a good positive correlation with cardiac T2*.ImportanceLeft ventricular strain using cardiac magnetic resonance feature tracking might be used as an adjunct in assessing cardiac functions in beta-thalassaemia major.

Health Status of Patients With β-Thalassemia in the West Bank: A Retrospective-Cohort Study

Management of β-thalassemia in developing countries is demanding in the absence of available therapies rather than recurrent transfusions. This study describes the characteristics and evaluates the hematological, biochemical, and hormonal findings of patients with β-thalassemia in the West Bank. We conducted a retrospective cohort study between January 2017 and December 2018. Data were collected through medical files of the patients with β-thalassemia from eight primary healthcare clinics, nine emergency departments, and 11 governmental hospitals across the West Bank. Results of the hematological, biochemical, and hormonal evaluations, in addition to demographic data and the use of iron chelation were included in the study and analyzed. A total of 309 patients with β-thalassemia were included with a male-to-female ratio of 1:1 and an average age of 23.4 ± 10.4 years. The anemic presentation was reported in 78.6% of the patients as indicated by hemoglobin level (mean ± SD = 8.4 ± 1.4 g/dl), and 73.1% had iron overload with serum ferritin (SF) levels ≥ 1,000 μg/L (mean ± SD = 317.8 ± 3,378.8 μg/L). Evaluation of the liver function tests showed that alanine transaminase (ALT) and aspartate transaminase (AST) levels were high among 38.1 and 61.2% of the patients, respectively. ALT and AST showed significant positive correlations with SF levels, while the kidney tests did not. As for iron chelation medications, patients receiving deferoxamine (26.5%) showed significantly higher SF levels compared with patients receiving deferasirox (73.5%). This study highlights the importance of establishing patient-tailored comprehensive assessment and follow-up protocols for the management of β-thalassemia with an emphasis on blood transfusion and iron chelation practices.

Long-Term Effects of Iron Chelating Agents on Ocular Function in Patients with Thalassemia Major

Background

The aim of this study is to evaluate eye structures and function in patients receiving iron chelating therapy and to assess whether a correlation exists between the onset of ocular alterations and the intake of iron chelating drugs.

Methods

A prospective cohort study was performed. Eighty-eight patients, composed of children and adults with thalassemia major (TM) who are taking or had taken iron chelating drugs (deferoxamine, deferiprone or deferasirox), have been initially enrolled in the study. The final sample featured 80 patients, including 18 children and 62 adults. These subjects received an eye examination to evaluate intraocular pressure (IOP), best corrected visual acuity (BCVA), the presence of refractive defects, cornea, anterior chamber, lens, fundus oculi, visual field and mean retinal nerve fiber layer (RNFL) thickness. Logistic regression model analysis was performed in order to assess any correlation. In addition, a literature search regarding the relation between iron chelating drugs and ocular adverse events was carried out to compare the results obtained with the evidence in the literature.

Results

Logistic regression did not report a significant correlation between the intake of iron chelating drugs and the onset of anterior ocular segment alterations, lens opacities, retinal diseases, optical neuropathies, astigmatism, visual field and RNFL thickness defects. Logistic regression returned a statistically significant correlation between myopia and iron chelation therapy (p-value 0.04; OR 1.05) and also between presbyopia and total duration of therapy with deferoxamine (p-value 0.03; OR 1.21). Although intraocular pressure levels remained within the normal range, a significant correlation with the length of deferoxamine therapy has been found (p-value 0.002; association coefficient -0.12). A negative correlation between deferiprone and presbyopia has also been observed.

Conclusion

Iron chelation therapy is not associated with severe visual function alterations. Limitation of deferoxamine treatment can help prevent ocular complications. Deferiprone and/or deferasirox may be preferable, especially in patients over age 40 years.

Erythrocyte transfusion restored heart rate variability in children with thalassemia major

Thalassemia major (TM) is a severe transfusion-dependent anemia. Regular erytrocyte transfusion is required for the treatment of thalassemia patients. However, repeated transfusion may result in impairements in heart function. In this study, we aimed to investigate short-term effects of erythrocyte transfusion on autonomic control of heart in children with thalassemia major. For that purpose heart rate variability (HRV), which is a non-invasive method used to evaluate the effects of the autonomic nervous system on the heart rhythym, was measured before and after erythrocyte transfusion and compared to the healthy controls. Children diagnosed with TM (n = 17) and sex and age matched healthy children (HC, n = 30) were included in the study. HRV values of TM patients were measured 5 min before erythrocyte transfusion (BET, n = 17) and 5 min after erythrocyte transfusion (AET, n = 17). Parameters of time-domain and frequency-domain of HRV were evaluated in all participants. Heart rate (HR) was higher in the BET than AET (P = 0.002) but there was no difference between AET and HC groups (P > 0.05). HRV parameters were lower in BET than AET (P < 0.05) but there were no statistical difference between AET and HC (P> 0.05). The data suggest that, in thalassemia major patients, erythrocyte transfusion restores HR and HRV parameters to the levels observed in healthy controls and, thus, in short-terms, appears to be beneficial for the autonomic control of the heart.

A narrative review of in utero gene therapy: advances, challenges, and future considerations

The field of in utero gene therapy (IUGT) represents a crossroad of technologic advancements and medical ethical boundaries. Several strategies have been developed for IUGT focusing on either modifying endogenous genes, replacing missing genes, or modifying gene transcription products. The list of candidate diseases such as hemoglobinopathies, cystic fibrosis, lysosomal storage disorders continues to grow with new strategies being developed as our understanding of their respective underlying molecular pathogenesis increases. Treatment in utero has several distinct advantages to postnatal treatment. Biologic and physiologic phenomena enable the delivery of a higher effective dose, generation of immune tolerance, and the prevention of phenotypic onset for genetic diseases. Therapeutic technology for IUGT including CRISPR-Cas9 systems, zinc finger nucleases (ZFN), and peptide nucleic acids (PNAs) has already shown promise in animal models and early postnatal clinical trials. While the ability to detect fetal diagnoses has dramatically improved with developments in ultrasound and next-generation sequencing, treatment options remain experimental, with several translational gaps remaining prior to implementation in the clinical realm. Complicating this issue, the potential diseases targeted by this approach are often debilitating and would otherwise prove fatal if not treated in some manner. The leap from small animals to large animals, and subsequently, to humans will require further vigorous testing of safety and efficacy.

Clinical Usefulness of Furosemide to Prevent Volume Overload Among Children and Young Adults with Transfusion-Dependent Thalassemia: A Randomized, Open-Label, Crossover Study

Purpose

Red blood cell transfusion is a key element of treatment among patients with transfusion-dependent thalassemia (TDT). Volume overload and HCC syndrome (hypertension, convulsion, and intracranial hemorrhage) are fatal complications related to transfusion. Furosemide has been widely used to prevent hypertension secondary to volume overload with unclear supportive evidence. This study aimed to evaluate the efficacy of furosemide to prevent volume overload among children and young adults diagnosed with TDT.

Methods

Patients diagnosed with TDT were enrolled and randomized to receive either furosemide pretransfusion or no furosemide pretransfusion. After 3 weeks to 4 months of wash-out periods, those patients underwent the alternate regimens as per crossover design of the study. Clinical and laboratory parameters including blood pressure and NT-proBNP levels were measured before and after each transfusion. The difference of those parameters between two randomized groups and their potential associated factors were analyzed.

Results

In all, 30 patients undergoing 60 red blood cell transfusions were enrolled in the study. All were randomized and crossover was designed as receiving and not receiving furosemide pretransfusion. No transfusion reactions, symptoms of volume overload and HCC syndrome were observed. No statistically significant correlation was found between pretransfusion furosemide and the difference between pre- and posttransfusion systolic blood pressure (2 mmHg systolic blood pressure difference in pretransfusion furosemide and 1.5 mmHg in no pretransfusion furosemide; p-value = 0.721), as well as between pretransfusion furosemide and the difference between pre- and posttransfusion NT-proBNP levels (−3.8 pg/mL NT-proBNP level difference in pretransfusion furosemide and −2.4 pg/mL in no pretransfusion furosemide; p-value = 0.490). No significant correlation was also observed even in selected patients with high NT-proBNP levels (p-value = 0.262). Associated factors affecting the difference between pre- and posttransfusion NT-proBNP levels were analyzed, and none of those were affected concerning the difference in the levels.

Conclusion

Furosemide has been included in standard transfusion guidelines in many institutions. Our study provided important evidence of the unnecessary use of the drug in preventing volume overload particularly in pediatric and young adult patients with TDT.

Thai Clinical Trials Registry (Tctr) Number

TCTR20180209001. Registered 6 February 2018, https://www.clinicaltrials.in.th/.

Association of HFE Gene Mutations With Serum Ferritin Level and Heart and Liver Iron Overload in Patients With Transfusion-dependent Beta-Thalassemia

OBJECTIVE

This study was performed on patients with transfusion-dependent beta-thalassemia (TDT) to investigate the effect of HFE gene mutations of iron overload in a large group of patients with TDT major and its relationship with heart and liver T2* magnetic resonance imaging (MRI) level.

MATERIALS AND METHODS

In a cross-sectional study, a total of 253 patients with TDT who had regular blood transfusion were included in this study. HFE gene mutations including H63D and C282Y were evaluated in all patients through molecular assay. Heart and liver T2* MRI results, types, duration of iron therapy, and the demographic data including age, gender, serum ferritin level, blood transfusion, and splenectomy history of the included participants were also collected, using a questionnaire.

RESULTS

Homozygous and heterozygous H63D mutation was found in 39.5% of the patients and C282Y mutation was found only in 1 patient. Ferritin level was significantly higher in patients with H63D mutation in comparison with patients without this mutation (P=0.036). Although heart T2* MRI and also the liver T2* MRI in the patients with H63D was slightly higher, the difference was not statistically significant. No significant correlation was observed between serum ferritin level and heart and liver T2* MRI, and iron chelation regimen.

DISCUSSION

Heart and liver iron overload was not significantly different between patients with and without H63D mutation. As for serum ferritin, it was significantly higher among patients with H63D mutation compared with patients without this mutation. Hence, it is recommended to consider HFE gene mutations among patients with thalassemia to reach a better iron overload evaluation and management.

Role of Red Cell Indices in Screening for Beta Thalassemia Trait: an Assessment of the Individual Indices and Application of Machine Learning Algorithm

Antenatal screening for beta thalassemia trait (BTT) followed by counseling of couples is an efficient way of thalassemia control. Since high performance liquid chromatography (HPLC) is costly, other cost-effective screening methods need to be devised for this purpose. The present study was aimed at evaluating the utility of red cell indices and machine learning algorithms including an artificial neural network (ANN) in detection of BTT among antenatal women. This cross-sectional study included all antenatal women undergoing thalassemia screening at a tertiary care hospital. Complete blood count followed by HPLC was performed. Receiver operating characteristic (ROC) curve analysis was performed for obtaining optimal cutoff for each of the indices with determination of test characteristics for detection of BTT. Machine learning algorithms including C4.5 and Naïve Bayes (NB) classifier and a back-propagation type ANN including the red cell indices was designed and tested. Over a period of 15 months, 3947 patients underwent thalassemia screening. BTT was diagnosed in 5.98% of women on the basis of HPLC. ROC analysis yielded the maximum accuracy of 63.8%, sensitivity and specificity of 66.2% and 63.7%, respectively for Mean corpuscular hemoglobin concentration (MCHC). The C4.5 and NB classifier had accuracy of 88.56%-82.49% respectively while ANN had an overall accuracy of 85.95%, sensitivity of 83.81%, and specificity of 88.10% in detection of BTT. The present study highlights that none of the red cell parameters standalone is useful for screening for BTT. However, ANN with combination of all the red cell indices had an appreciable sensitivity and specificity for this purpose. Further refinements of the neural network can provide an appropriate tool for use in peripheral settings for thalassemia screening.

Prenatal diagnosis of a rare β-thalassemia gene －90 (C>T) (HBB: c.-140 C>T) mutation associated with deletional Hb H disease (--SEA /-α4.2 )

Background

Hemoglobin H (Hb H) disease can be caused by compound heterozygosity for two different mutations or from homozygotes for mutations, and conventional genetic methods may lead to misdiagnosis when Hb H disease is combined with a rare β‐thalassemia.

Methods

Hematology parameters and hemoglobin electrophoresis analysis, gap‐polymerase chain reaction (gap‐PCR) and reverse dot‐blot hybridization (RDB‐PCR) were employed to identify common α‐thalassemia and Hb H disease. Rare β‐thalassemia mutations were detected by DNA sequencing.

Results

Hematological analysis and hemoglobin electrophoresis revealed a mild anemia α⁰‐thalassemia trait (Hb 90 g/L, MCV 71 fL, and MCH 22.7 pg) compound with β⁺‐thalassemia trait (MCV 71 fL, MCH 22.7 pg, and HbA2 5.51%) for the pregnant woman. DNA sequencing for the β‐globin gene revealed rare a －90 (C>T) (HBB: c.‐140 C>T) mutation for the woman. DNA analysis identified that the fetus inherited the α⁰‐thalassemia mutation [‐‐^SEA (Southeast Asian)] and a rare β⁺‐thalassemia mutation －90 (C>T) (HBB: c.‐140 C>T) from the mother, and the α⁺‐thalassemia mutation [‐α^4.2 (leftward)] from the father.

Conclusion

We reported a rare －90 (C>T) (HBB: c.‐140 C>T) mutation combined with the ‐‐^SEA/‐α^4.2 in a family. This finding enriched the mutation spectrum of thalassemia molecular characteristics in China and emphasized the significance in DNA sequencing in mutation screening for the families with thalassemia.

Novel genetic therapeutic approaches for modulating the severity of β-thalassemia (Review)

Thalassemia is a genetic haematological disorder that arises due to defects in the α and β-globin genes. Worldwide, 0.3-0.4 million children are born with haemoglobinopathies per year. Thalassemic patients, as well as their families, face various serious clinical, socio-economic, and psychosocial challenges throughout their life. Different therapies are available in clinical practice to minimize the suffering of thalassemic patients to some extent and potentially cure the disease. Predominantly, patients undergo transfusion therapy to maintain their haemoglobin levels. Due to multiple transfusions, the iron levels in their bodies are elevated. Iron overload results in damage to body organs, resulting in heart failure, liver function failure or endocrine failure, all of which are commonly observed. Certain drugs have been developed to enhance the expression of the γ-gene, which ultimately results in augmentation of fetal haemoglobin (HbF) levels and total haemoglobin levels in the body. However, its effectiveness is dependent on the genetic makeup of the individual patient. At present, allogeneic haematopoietic Stem Cell Transplantation (HSCT) is the only practically available option with a high curative rate. However, the outcome of HSCT is strongly influenced by factors such as age at transplantation, irregular iron chelation history before transplantation, histocompatibility, and source of stem cells. Gene therapy using the lentiglobin vector is the most recent method for cure without any mortality, graft rejection and clonal dominance issues. However, delayed platelet engraftment is being reported in some patients. Genome editing is a novel approach which may be used to treat patients with thalassemia; it makes use of targeted nucleases to correct the mutations in specific DNA sequences and modify the sequence to the normal wild-type sequence. To edit the genome at the required sites, CRISPR/Cas9 is an efficient and accurate tool that is used in various genetic engineering programs. Genome editing mediated by CRISPR/Cas9 has the ability to restore the normal β-globin function with minimal side effects. Using CRISPR/Cas9, expression of BCL11A can be downregulated along with increased production of HbF. However, these genome editing tools are still under in-vitro trials. CRISPR/Cas9 has can be used for precise transcriptional regulation, genome modification and epigenetic editing. Additional research is required in this regard, as CRISPR/Cas9 may potentially exhibit off-target activity and there are legal and ethical considerations regarding its use.

Analysis of Hb levels and degree of anemia in relation to genotype in 615 patients with hemoglobin H disease

OBJECTIVES

We analyzed hemoglobin (Hb) levels and degree of anemia in relation to genotype in patients with hemoglobin H (Hb H) disease, thereby providing a scientific basis for the prevention and treatment of Hb H disease in the Guangxi region of China.

METHODS

Hb analysis was conducted in 615 patients using high performance liquid chromatography. Seven α-thalassemia and 17 β-thalassemia genotypes commonly found in the Chinese population were detected by Gap-polymerase chain reaction and reverse dot hybridization. Multiple ligation-dependent probe amplification and sequencing were used to detect α-globin gene.

RESULTS

On analyzing the degree of anemia, we found that the proportion of severe and moderate anemia was the highest among cases with - ^SEA/α^CSα genotype, followed by - ^SEA/α^QSα. When Hb H disease was present in combination with β-thalassemia, the clinical symptoms of most patients were milder than those with simple Hb H disease.

CONCLUSION

The clinical manifestations of various types of Hb H disease are heterogeneous; the Hb levels of patients with deletional Hb H are generally higher than those with non-deletional Hb H (P < 0.05). In-depth knowledge of the gene mutation spectrum of thalassemia in Guangxi can provide a basis for genetic counseling of couples and enable prenatal diagnosis.

Early detection of ventricular dysfunction by tissue Doppler echocardiography related to cardiac iron overload in patients with thalassemia

Cardiac T2* MRI is used as a gold standard for cardiac iron quantification in patients with transfusion-dependent thalassemia (TDT). We hypothesized that left ventricular (LV) diastolic dysfunction would reflect the severity of iron overload and can serve as an early detection of cardiac iron deposits. A study was conducted on all patients with TDT. Hemoglobin, serum ferritin and non-transferrin bound iron, together with a complete echocardiography and cardiac T2* MRI, were performed on all patients. Seventy-seven patients with TDT were enrolled (median age 14 years). In the patient group with a mean serum ferritin of > 2500 ng/mL during the past 12 months, there were more patients with severe cardiac iron deposits than in the group with a mean serum ferritin of ≤ 2500 ng/mL. Diastolic dysfunction was absent in all patients with a serum ferritin of < 1000 ng/mL. All patients with cardiac T2* ≤ 20 ms had grade III LV diastolic dysfunction. However, twenty-one percent of patients with cardiac T2* > 20 ms had LV diastolic dysfunction. The differences observed in pulmonary vein atrial reversal duration and mitral A-wave (PVAR-MVA) duration ≥ - 1 ms and an E/E' ratio ≥ 11 were proven to be the associated factors with the cardiac T2* ≤ 20 ms. Increased PVAR-MVA duration and increased E/E' ratio reliably reflected a severe iron overload, according to a cardiac T2* in patients with TDT. LV diastolic dysfunction can occur prior to severe cardiac iron deposition. Tissue Doppler echocardiography has the potential for the early detection of cardiac involvement in patients with TDT .

The role of iron repletion in adult iron deficiency anemia and other diseases

Iron deficiency anemia (IDA) is the most prevalent and treatable form of anemia worldwide. The clinical management of patients with IDA requires a comprehensive understanding of the many etiologies that can lead to iron deficiency including pregnancy, blood loss, renal disease, heavy menstrual bleeding, inflammatory bowel disease, bariatric surgery, or extremely rare genetic disorders. The treatment landscape for many causes of IDA is currently shifting toward more abundant use of intravenous (IV) iron due to its effectiveness and improved formulations that decrease the likelihood of adverse effects. IV iron has found applications beyond treatment of IDA, and there is accruing data about its efficacy in patients with heart failure, restless leg syndrome, fatigue, and prevention of acute mountain sickness. This review provides a framework to diagnose, manage, and treat patients presenting with IDA and discusses other conditions that benefit from iron supplementation.

Splenectomy for people with thalassaemia major or intermedia

BACKGROUND

Thalassaemia is a genetic disorder of the haemoglobin protein in red blood cells. It has been historically classified into thalassaemia minor, intermedia and major, depending on the genetic defect and severity of the disease. The clinical presentation of β-thalassaemia varies widely from a mild asymptomatic form in thalassaemia minor, to a severe disease in thalassaemia major where individuals are dependant on life-long blood transfusions. The hallmark of thalassaemia syndromes is the production of defective red blood cells that are removed by the spleen resulting in an enlarged hyperfunctioning spleen (splenomegaly). Removal of the spleen may thus prolong red blood cell survival by reducing the amount of red blood cells removed from circulation and may ultimately result in the reduced need for blood transfusions.

OBJECTIVES

To assess the efficacy and safety of splenectomy in people with β-thalassaemia major or intermedia.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Review Group's Haemoglobinopathies Trials Register, compiled from searches of electronic databases and the handsearching of journals and conference abstract books. We also searched online trial registries and the reference lists of relevant articles and reviews (27 July 2018).Date of the most recent search of the Group's trials register: 02 August 2019.

SELECTION CRITERIA

We included randomised controlled and quasi-randomised controlled studies of people of any age with thalassaemia major or intermedia, evaluating splenectomy in comparison to conservative treatment (transfusion therapy and iron chelation) or other forms of splenectomy compared to each other (laparoscopic, open, radio-frequency).

DATA COLLECTION AND ANALYSIS

Two authors independently selected and extracted data from the single included study using a customised data extraction form and assessed the risk of bias. The quality of the evidence was assessed using GRADE.

MAIN RESULTS

One study, including 28 participants was included in the review; the results were described, primarily, in a narrative manner. This study assessed the feasibility of splenectomy using a laparoscopic approach versus open surgery. Given the lack of detail regarding the study methods beyond randomisation, the overall risk of bias for this study was unclear. The study was carried out over a period of 3.5 years, with each participant followed up only until discharge (less than one week after the intervention); it did not assess the majority of the outcomes outlined in this review (including two of the three primary outcomes, frequency of transfusion and quality of life). A total of three serious post-operative adverse events (the review's third primary outcome) were reported in the laparoscopic splenectomy group (one case of atelectasis and two cases of bleeding), compared to two events of atelectasis in the open surgery group; however, there were no significant differences between the groups for either atelectasis, risk ratio (RR) 0.50 (95% confidence interval (CI) 0.05 to 4.90) or for bleeding, RR 5.00 (95% CI 0.26 to 95.61) (very low-quality evidence). In addition, the study also reported three serious cases of intra-operative bleeding in the laparoscopic group which mandated conversion to open surgery, although the difference between groups was not statistically significant, RR 7.00 (95% CI 0.39 to 124.14) (very low-quality evidence). These effect estimates are based on very small numbers and hence are unreliable and imprecise. From this small study, there appeared to be an advantage for the laparoscopic approach, in terms of post-operative hospital stay, although the group difference was not large (median difference of 1.5 days, P = 0.03).

AUTHORS' CONCLUSIONS

The review was unable to find good quality evidence, in the form of randomised controlled studies, regarding the efficacy of splenectomy for treating thalassaemia major or intermedia. The single included study provided little information about the efficacy of splenectomy, and compared open surgery and laparoscopic methods. Further studies need to evaluate the long-term effectiveness of splenectomy and the comparative advantages of surgical methods. Due to a lack of high quality evidence from randomised controlled studies, well-conducted observational studies may be used to answer this question.

Computer and mobile technology interventions to promote medication adherence and disease management in people with thalassemia

BACKGROUND

Thalassemia syndromes are inherited hemoglobin disorders that result when the synthesis of normal hemoglobin is lacking or significantly reduced. For people with thalassemia, long-term red blood cell transfusion remains the mainstay of therapy, which may lead to iron overload causing severe complications and damage in different body organs. Long-term iron chelation therapy is essential for people with thalassemia to minimize the ongoing iron-loading process. In addition, suboptimal adherence can increase adverse events associated with iron overload and result in increased morbidity, mortality, healthcare utilization and cost of care.

OBJECTIVES

To identify and assess the effects of computer and mobile technology interventions designed to facilitate medication adherence and disease management in individuals with thalassemia, including:- evaluating the effects of using computer and mobile technology interventions for medication adherence and disease management on health and behavioral outcomes;- identifying and assessing the effects of computer and mobile technology interventions specific to different age groups (children, adolescents and adults) and type of modality (e.g. cell phone, the Internet).

SEARCH METHODS

We searched CENTRAL (the Cochrane Library), MEDLINE, Embase, CINAHL, PsycINFO, ProQuest Dissertations & Theses Global, Psychology and Behavioral Sciences Collection, Web of Science Science & Social Sciences Conference Proceedings Indexes, IEEE Xplore and ongoing trial databases (22 February 2018). We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register (20 June 2019). We also searched for unpublished work in the abstract book of nine major conferences in the related field.

SELECTION CRITERIA

Randomized controlled trials (RCT) and quasi-RCTs comparing single- or multi-component interventions versus no intervention, placebo or standard care, with adherence to iron chelation as the primary outcome were eligible for inclusion. Non-randomized studies of interventions, controlled before-after studies, and interrupted-time-series studies were also eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed study eligibility. If we had included any studies, we would have independently assessed risk of bias and extracted data; we planned to assess the quality of the evidence using GRADE.

MAIN RESULTS

We did not identify any eligible studies for inclusion in the review.

AUTHORS' CONCLUSIONS

Due to lack of evidence, we cannot comment on the efficacy or effectiveness of computer and mobile technology intervention strategies to promote disease management and adherence to iron chelation therapy in people with thalassemia.We concluded that RCTs are needed to examine a variety of computer and mobile technology intervention strategies that may be useful for promoting disease management and increasing adherence to iron chelation therapy in individuals with thalassemia.

Splenectomy to Optimize Hemoglobin S Control in Children With Sickle Cell Anemia on Chronic Transfusion Therapy for Stroke Prevention

Chronic transfusion therapy with the goal of maintaining a hemoglobin (Hb) S <30% is the primary recommended treatment for children with sickle cell anemia and a history of overt stroke or abnormal transcranial Doppler examination. We report chronic hypersplenism as a cause of poor HbS% control in 3 children on chronic transfusion therapy for stroke prevention. Splenectomy resulted in a 39.77% (95% confidence interval, 34.3-45.3, P<0.0001) mean reduction in HbS% with no perioperative or infectious complications suggesting the need for additional research into splenectomy as a therapeutic option for select high-risk children to optimize transfusion therapy for stroke prevention.

N-terminal-pro-b-type natriuretic peptide levels and cardiac hemosiderosis in adolescent β-thalassemia major patients

Background:

Iron-induced cardiomyopathy remains the leading cause of mortality in patients with β-thalassemia major. Iron overload cardiomyopathy, which may be reversible through iron chelation, is characterized by early diastolic dysfunction. Amino-terminal pro-brain natriuretic peptide (NT-proBNP) is a sensitive biomarker of diastolic dysfunction.

Aim:

The aim of the study is to evaluate the diagnostic value of NT-proBNP as a surrogate marker of iron overload examined with magnetic resonance imaging T2-star (MRI T2*).

Methods:

Sixty-eight β-thalassemia major patients (10–18 years) with no signs of heart failure underwent NT-proBNP measurement before routine transfusion. All participants prospectively underwent cardiac MRI T2* examination within 3 months (median 19 days). Patients were divided as cardiac hemosiderosis (cardiac MRI T2* <20 ms) and nonhemosiderosis (cardiac MRI T2* >20 ms).

Results:

Of 68 patients, the male-to-female ratio was 1:1.1 and the median age was 14.1 years (range: 10–17.8 years). NT-proBNP levels were not different between hemosiderosis and nonhemosiderosis patients (P = 0.233). Further receiver operating characteristic analysis resulted in no significant correlation of NT-proBNP and MRI T2* (area under the curve 0.393, P = 0.233).

Conclusion:

Measurement of NT-proBNP levels cannot be used for early detection of cardiac iron overload in adolescent with β-thalassemia major.

Assessment of thiol/disulfide balance as an oxidative stress marker in children with β-thalassemia major

Objective:

We aimed to investigate the oxidative stress status in children with β-thalassemia major (β-TM) by measuring native thiol (SH), disulfide (SS) and total thiol (SH + SS) plasma levels.

Methods:

This study was carried out from November 2017 to March 2018 at the Pediatric Hematology Clinic of the Harran University Medical Faculty Hospital. Blood specimens were collected from 100 participants, including 50 β-TM patients and 50 controls, and SH, SS and SH+SS levels were detected through a newly developed method.

Results:

SH, SS, SH+SS levels and SS/SH ratio were markedly higher in β-TM patients than in controls. In β-TM group, SH and SH+SS levels were positively correlated with age, albumin and total bilirubin. Serum ferritin level was positively correlated with SH, SH+SS, aspartate transaminase and alanine transaminase.

Conclusions:

We found that the SS/SH ratio was high in patients with β-TM, which shows increased oxidative stress. This ratio may be considered as a tool for the determination of oxidative status in such patients due to easily calculate, suitable for routine use and economical.

The effect of splenectomy on complement regulatory proteins in erythrocytes in β-thalassemia major

INTRODUCTION

Hemolysis due to ineffective erythropoiesis is a serious problem β-thalassemia major (β-TM) patients. The role of complement system in the etiopathogenesis of hemolysis observed in β-TM were released. Hemolysis induced by activation of complement system is prevented by complement regulatory proteins. Decay accelerating factor (CD55), membrane inhibitor of reactive lysis (CD59), and complement reception 1 (CR1, CD35) are among these proteins. The absence of these proteins thus accounts for the increased susceptibility of erythrocytes to complement lysis. Splenomegaly and hypersplenism are common complications among thalassemia major patients necessitating splenectomy.

MATERIAL AND METHODS

In this study we investigated how splenectomy effects complement regulatory system in erythrocytes. We analysed CD35, CD55, and CD59 levels on erythrocytes in β-TM by flow cytometry.

RESULTS

The overall mean percentage of CD55 and CD35 positive RBCs of group 1 (22 β-TM with splenectomy) was significantly lower than group 2 (23 β-TM without splenectomy) and group 3 (healthy controls) (p < 0.05). The overall mean percentage CD59 positive RBCs of patients was no significantly different in all groups. The levels of CD35 and CD55 expression on the erythrocytes of splenectomized patients was significantly lower than non-splenectomized patients (p < 0.05).

CONCLUSIONS

Increased erythrocyte destruction and iron deposition in organs due to deficiency of these regulatory proteins may be the underlying mechanism of organ damage developing in β-TM patients.

Prenatal diagnosis of a case with SEA-HPFH deletion thalassemia with whole HBB gene deletion

OBJECTIVE

The thalassemias is a group of hereditary disorders with impaired production of functional hemoglobin. In this report we described a rare case of compound heterozygous mutation of South-East Asia type hereditary persistence of fetal hemoglobin (SEA-HPFH) and β -thalassemia that allowed prenatal diagnosis to be performed in a subsequent pregnancy in the family.

CASE REPORT

The father showed a SEA-HPFH thalassemia trait phenotype, while his genotype revealed that he was heterozygous for the SEA-HPFH deletion; The mother genotype was heterozygote for IVS-II-654 mutation; the second child had co-inherited both parental mutations and was, thus, a compound heterozygote for β-thalassemia (IVS-II-654)/SEA-HPFH deletion. His phenotype was intermediate β-thalassemia. Prenatal genotyping of a fetal sample during the third pregnancy confirmed the fetus was only heterozygote for SEA-HPFH deletion and the parents elected to continue the pregnancy.

CONCLUSION

We described the clinical and molecular characterization of the first detected case of compound β-Thalassemia/SEA-HPFH deletion in Northern Vietnam. The report also highlighted the accuracy and necessity of mutation screening for families with thalassemia to inform accurate genetic counseling and targeted prenatal diagnosis when desired.

Efficacy of Oral Acetaminophen and Intravenous Chlorpheniramine Maleate versus Placebo to Prevent Red Cell Transfusion Reactions in Children and Adolescent with Thalassemia: A Prospective, Randomized, Double-Blind Controlled Trial

Background

Thalassemia is a common congenital hemolytic disorder. In severe cases, regular blood transfusion is essentially required. The role of premedications to prevent transfusion reactions is varied among institutions with no standard guideline.

Objective

To prospectively compare the risk of transfusion reactions in thalassemia patients premedicated with acetaminophen and chlorpheniramine maleate (CPM) versus placebo prior to blood transfusion.

Material and Method

A randomized, double-blinded, placebo-controlled transfusion reaction study of 147 eligible patients was analyzed. All administered red blood cell (RBC) products were leukoreduced blood products. Patients were monitored and followed for the development of transfusion reactions for 24 hours after RBC transfusion.

Results

A total of 73 patients randomized to receive active drugs consisting of acetaminophen and CPM were compared to 74 patients receiving placebo. The overall incidences of febrile reaction and urticarial rash were 6.9% and 22% in the patients randomized to receive active drugs comparing with 9.5% and 35.2% in the patients receiving placebo with no significant differences between two groups. However, delayed development of urticarial rash at 4-24 hours after RBC transfusion was significantly higher in female and patients receiving placebo.

Conclusion

Administration of premedications in thalassemia patients receiving RBC transfusion without a history of transfusion reactions does not decrease the overall risk of transfusion reactions. However, the use of CPM might be beneficial to prevent delayed urticarial rash in those patients especially in females (Thai Clinical Trial Registry (TCTR) study ID: 20140526001).

New Bioinformatics-Based Discrimination Formulas for Differentiation of Thalassemia Traits From Iron Deficiency Anemia

Thalassemia traits (TTs) and iron deficiency anemia (IDA) are the most common disorders of hypochromic microcytic anemia (HMA). The present study aimed to differentiate TTs from IDA by analyzing discrimination formulas and provides comprehensive data of hemoglobin disorders prevalent in Pakistan. Among 12 published discrimination formulas, 6 formulas-MI, EF, G&K, RDWI, R, and HHI-were the most reliable to discriminate TTs from IDA. The failure cutoff values were improved by the random forest (RF) decision-tree approach. Moreover, the Shine and Lal (S&L) formula, which completely failed to discriminate IDA from TTs with original cutoff value (<1530), improved with the use of new proposed cutoff value (<1016) and was found to successfully discriminate all cases of TTs from those with IDA. In addition, 2 newly proposed formulas discriminated TTs from IDA more reliably than the original 12 formulas assessed. The proposed formulas could play a crucial role for clinicians to discriminate between TTs and IDA.

α+-Thalassemia Caused by an 811 bp Deletion in Individuals from Nanning, Guangxi: A Report of Two Cases

A novel 811 bp deletion was first identified in two families of Nanning City, Guangxi Zhuang Autonomous Region, People's Republic of China (PRC). The molecular basis of this anomaly is a deletion from NG_000006.1: g.32945_33755, and is 20 bp upstream of the translation initiation codon of HBA2. From analyses of the blood indices of the two probands, the 811 bp deletion is an α⁺-thalassemia (α⁺-thal). This is the first report of this deletional thalassemia anywhere in the world.

Prevalence of Thalassemia Traits and Iron Deficiency Anemia in Sindh, Pakistan

Among microcytic hypochromic anemias, the most common disorders are iron deficiency anemia and co-pathological conditions such as α- or β-thalassemia (α- or β-thal) traits. The aim of the present study was to determine the frequency and prevalence of iron deficiency anemia and α- or β-thal traits based on clinical laboratory data across different ethnic groups in five districts of Sindh Province, Pakistan. The present retrospective study analyzed 3 years (2012-2015) of encoded and unlinked clinical laboratory data, and identified 3030 microcytic hypochromic anemia cases. The data contained complete blood counts (CBCs) with smear morphology examinations, serum ferritin levels, and hemoglobin (Hb) electrophoreses. After reviewing the data, 994 confirmed subjects (iron deficiency anemia and α- and β-thal traits) were then selected for the present study. The prevalence of α- and β-thal traits was highest in Badin district (35.27%), while the prevalence of iron deficiency anemia was highest in Larkana district (30.73%). According to the ethnic-wise distribution, higher numbers of α- and β-thal trait cases were seen in the Sindhi ethnic group [375 (64.21%) and 283 (69.02%), respectively] than in the other ethnic groups. In addition, a higher distribution of β-thal trait cases was observed in the Sindhi ethnic group [n = 327 (56%)] in α- and β-thal cases overall. Findings from the present study strongly suggested that screening is important not only for β-thal trait but also other traits as well. However, careful monitoring of CBC parameters, including red blood cell (RBC) indices and morphology, along with clinical findings are essential to diagnose carrier cases, especially in high prevalence areas.

Anemia for the Primary Care Physician

Anemia denotes a reduced red blood cell (RBC) mass from any cause. The causes of anemia are numerous and due to decreased (or abnormal) erythropoesis, shortened RBC life span, or blood loss. The most common etiology of anemia is iron deficiency. A judicious work up of anemia includes evaluating the reticulocyte count and peripheral smear. The severity of illness of a patient with anemia is determined by the degree of anemia and the seriousness of the underlying disorder. Management of patients with hereditary and hemolytic anemias should involve a hematologist.

Unusual Anemias

Many processes lead to anemia. This review covers anemias that are less commonly encountered in the United States. These anemias include hemoglobin defects like thalassemia, bone marrow failure syndromes like aplastic anemia and pure red cell aplasia, and hemolytic processes such as paroxysmal nocturnal hemoglobinuria. The pathogenesis, diagnostic workup, and treatment of these rare anemias are reviewed.

Circulating microparticles and the risk of thromboembolic events in Egyptian beta thalassemia patients

The presence of elevated numbers of circulating microparticles (MPs) has been hypothesized to be responsible for the occurrence of thromboembolic events (TEEs) in thalassemic patients. Our aim is to evaluate the presence and the thrombotic risk of circulating MPs in thalassemia patients and to determine the difference in MPs between β-thalassemia major (β-TM) and thalassemia intermedia (TI). The percentage of the annexin-labeled MPs, platelet-derived MPs (PMPs), erythrocyte-derived MPs (RMPs), and endothelial-derived MPs (EMPs) was measured by flow cytometry, in 87 thalassemia patients (39 β-TM and 48 TI). By multiple regression analysis, we then assessed the various independent risk factors for the occurrence of TEE. The thalassemic patients who experienced TEE had a significantly higher platelet count, higher percentage of annexin-labeled MPs, and higher percentage of PMPs (p value = 0.014, 0.003, and 0.014, respectively). There was no significant difference between β-TM and TI patients at the level of any of the studied MPs. The predictive risk factors for TEE in thalassemic patients were splenectomy, total and direct bilirubin, the RMPs, and the EMPs (OR = 10.07 (CI = 3.7-27.1), 4.3 (CI = 2.1-8.7), 1.4 (CI = 1.5-6.2), 1.6 (CI = 1.1-2.2), 3.0 (CI = 1.9-4.9), respectively). In conclusion, the elevated numbers of circulating MPs is a risk factor for the TEE in thalassemia patients.

Mutation in a Highly Conserved COOH-Terminal Residue of Krüppel-Like Factor 1 Associated with Elevated Hb F in a Compound Heterozygous β-Thalassemia Patient with a Nontransfusion-Dependent Thalassemia Phenotype

We present a patient with a compound heterozygosity codon 39 (C > T) (β⁰) [or β39(C5)Gln→Stop (G39X); CAG > TAG; HBB: c.118C > T] and -87 (C > T) (β⁺) (HBB: c.-137C > T) β-globin mutations, a non transfusion-dependent thalassemia phenotype and 97.0% fetal hemoglobin. A novel heterozygous mutation was identified in a highly conserved residue in the COOH-terminus of the Krüppel-like factor 1, R360H, that likely altered DNA-binding and impaired transactivation.

Heart Rate Variability for Early Detection of Cardiac Iron Deposition in Patients with Transfusion-Dependent Thalassemia

Background

Iron overload cardiomyopathy remains the major cause of death in patients with transfusion-dependent thalassemia. Cardiac T2* magnetic resonance imaging is costly yet effective in detecting cardiac iron accumulation in the heart. Heart rate variability (HRV) has been used to evaluate cardiac autonomic function and is depressed in cases of thalassemia. We evaluated whether HRV could be used as an indicator for early identification of cardiac iron deposition.

Methods

One hundred and one patients with transfusion-dependent thalassemia were enrolled in this study. The correlation between recorded HRV and hemoglobin, non-transferrin bound iron (NTBI), serum ferritin and cardiac T2* were evaluated.

Results

The median age was 18 years (range 8–59 years). The patient group with a 5-year mean serum ferritin >5,000 ng/mL included significantly more homozygous β-thalassemia and splenectomized patients, had lower hemoglobin levels, and had more cardiac iron deposit than all other groups. Anemia strongly influenced all domains of HRV. After adjusting for anemia, neither serum ferritin nor NTBI impacted the HRV. However cardiac T2* was an independent predictor of HRV, even after adjusting for anemia. For receiver operative characteristic (ROC) curve analysis of cardiac T2* ≤20 ms, only mean ferritin in the last 12 months and the average of the standard deviation of all R-R intervals for all five-minute segments in the 24-hour recording were predictors for cardiac T2* ≤20 ms, with area under the ROC curve of 0.961 (p<0.0001) and 0.701 (p = 0.05), respectively.

Conclusions

Hemoglobin and cardiac T2* as significant predictors for HRV indicate that anemia and cardiac iron deposition result in cardiac autonomic imbalance. The mean ferritin in the last 12 months could be useful as the best indicator for further evaluation of cardiac risk. The ability of serum ferritin to predict cardiac risk is stronger than observed in other thalassemia cohorts. HRV might be a stronger predictor of cardiac iron in study populations with lower somatic iron burdens and greater prevalence of cardiac iron deposition.

A new index to discriminate between iron deficiency anemia and thalassemia trait

Background

The most common microcytic and hypochromic anemias are iron deficiency anemia and thalassemia trait. Several indices to discriminate iron deficiency anemia from thalassemia trait have been proposed as simple diagnostic tools. However, some of the best discriminative indices use parameters in the formulas that are only measured in modern counters and are not always available in small laboratories.

The development of an index with good diagnostic accuracy based only on parameters derived from the blood cell count obtained using simple counters would be useful in the clinical routine. Thus, the aim of this study was to develop and validate a discriminative index to differentiate iron deficiency anemia from thalassemia trait.

Methods

To develop and to validate the new formula, blood count data from 106 (thalassemia trait: 23 and iron deficiency: 83) and 185 patients (thalassemia trait: 30 and iron deficiency: 155) were used, respectively. Iron deficiency, β-thalassemia trait and α-thalassemia trait were confirmed by gold standard tests (low serum ferritin for iron deficiency anemia, HbA₂ > 3.5% for β-thalassemia trait and using molecular biology for the α-thalassemia trait).

Results

The sensitivity, specificity, efficiency, Youden's Index, area under receiver operating characteristic curve and Kappa coefficient of the new formula, called the Matos & Carvalho Index were 99.3%, 76.7%, 95.7%, 76.0, 0.95 and 0.83, respectively.

Conclusion

The performance of this index was excellent with the advantage of being solely dependent on the mean corpuscular hemoglobin concentration and red blood cell count obtained from simple automatic counters and thus may be of great value in underdeveloped and developing countries.

Thalassemia and risk of dementia: a nationwide population-based retrospective cohort study

BACKGROUND

This study is a nationwide population-based retrospective cohort study to investigate the risk for developing dementia in thalassemia population.

METHODS

In a longitudinal cohort of 1 million insured people, we identified 871 thalassemia patients who were newly diagnosed between 2000 and 2004 and selected a comparison cohort of 3484 subjects without thalassemia. We analyzed the risks for thalassemia and dementia using Cox proportional hazard regression models to assess the dementia risk in thalassemia patients after adjusting for age, gender, insured amount, urbanization and comorbidities.

RESULTS

The overall risks for developing dementia were 1.88-fold (95% CI=1.10-3.21) in patients with thalassemia compared with the comparison cohort after adjusting for age, sex, insured amount, urbanization and comorbidities. The combined effects measured for patients afflicted with thalassemia and the comorbidities of diabetes, hypertension, CAD, head injury, depression, CKD, or substance-related disorder exhibited a significant association with hyperlipidemia risk compared with that measured for patients without thalassemia and without any counterpart comorbidities. In subgroup analysis, the HRs of dementia increased, from 1.69 (95% CI=0.93-3.07) for those who had not undergone transfusion to 2.72 (95% CI=1.09-6.78) for those experienced transfusion compared with the no thalassemia cohort (p for trend<0.01).

CONCLUSION

Our long-term cohort study result showed that thalassemia should be considered a crucial risk factor for developing dementia.

Zinc status affects glucose homeostasis and insulin secretion in patients with thalassemia

Up to 20% of adult patients with Thalassemia major (Thal) live with diabetes, while 30% may be zinc deficient. The objective of this study was to explore the relationship between zinc status, impaired glucose tolerance and insulin sensitivity in Thal patients. Charts from thirty subjects (16 male, 27.8 ± 9.1 years) with Thal were reviewed. Patients with low serum zinc had significantly lower fasting insulin, insulinogenic and oral disposition indexes (all p < 0.05) and elevated glucose response curve, following a standard 75 g oral load of glucose compared to those with normal serum zinc after controlling for baseline (group × time interaction p = 0.048). Longitudinal data in five patients with a decline in serum zinc over a two year follow up period (−19.0 ± 9.6 μg/dL), showed consistent increases in fasting glucose (3.6 ± 3.2 mg/dL) and insulin to glucose ratios at 120 min post glucose dose (p = 0.05). Taken together, these data suggest that the frequently present zinc deficiency in Thal patients is associated with decreased insulin secretion and reduced glucose disposal. Future zinc trials will require modeling of oral glucose tolerance test data and not simply measurement of static indices in order to understand the complexities of pancreatic function in the Thal patient.

Risk of coronary artery disease in transfusion-naïve thalassemia populations: A nationwide population-based retrospective cohort study

OBJECTIVE

Few studies have focused on the association between coronary artery disease (CAD) and transfusion naïve thalassemia populations (this term means silent carrier, thalassemia minor or intermedia), who usually had less clinical manifestations and didn't require frequently blood transfusion.

DESIGN, SETTING AND PATIENTS

This nationwide population-based cohort study involved analyzing data obtained between 1998 and 2010 from the Taiwanese National Health Insurance Research Database, with a follow-up period extending to the end of 2011. We identified patients with thalassemia and selected a comparison cohort that was frequency matched with the patients with thalassemia according to age, sex, and diagnosis year at a ratio of 1 patient with thalassemia to 4 control patients. We analyzed the risks of thalassemia and CAD by using Cox proportional hazard regression models.

MEASUREMENTS AND MAIN RESULTS

In this study, 1537 patients with thalassemia and 6418 controls were included. The overall risks of developing CAD were 1.5-fold in patients with thalassemia compared with those in the comparison cohort after adjustment for age, sex, and comorbidities. Patients with thalassemia and with comorbidities, including hypertension, diabetes, hyperlipidemia, and chronic obstructive pulmonary disease, were 3.73-fold more likely to develop CAD than those without thalassemia and comorbidity (95% confidence interval=2.41-5.79).

CONCLUSION

This is the first large long-term cohort study of which the results showed that that transfusion-naïve thalassemia populations should be considered a crucial risk factor for CAD, even in patients with relatively mild clinical manifestations of thalassemia.

Factor-induced Reprogramming and Zinc Finger Nuclease-aided Gene Targeting Cause Different Genome Instability in β-Thalassemia Induced Pluripotent Stem Cells (iPSCs)

The generation of personalized induced pluripotent stem cells (iPSCs) followed by targeted genome editing provides an opportunity for developing customized effective cellular therapies for genetic disorders. However, it is critical to ascertain whether edited iPSCs harbor unfavorable genomic variations before their clinical application. To examine the mutation status of the edited iPSC genome and trace the origin of possible mutations at different steps, we have generated virus-free iPSCs from amniotic cells carrying homozygous point mutations in β-hemoglobin gene (HBB) that cause severe β-thalassemia (β-Thal), corrected the mutations in both HBB alleles by zinc finger nuclease-aided gene targeting, and obtained the final HBB gene-corrected iPSCs by excising the exogenous drug resistance gene with Cre recombinase. Through comparative genomic hybridization and whole-exome sequencing, we uncovered seven copy number variations, five small insertions/deletions, and 64 single nucleotide variations (SNVs) in β-Thal iPSCs before the gene targeting step and found a single small copy number variation, 19 insertions/deletions, and 340 single nucleotide variations in the final gene-corrected β-Thal iPSCs. Our data revealed that substantial but different genomic variations occurred at factor-induced somatic cell reprogramming and zinc finger nuclease-aided gene targeting steps, suggesting that stringent genomic monitoring and selection are needed both at the time of iPSC derivation and after gene targeting.

Discrimination index of microcytic anemia in young soldiers: a single institutional analysis

Background

The common differential diagnosis of microcytic anemia in young Asian men includes iron deficiency anemia (IDA), α-thalassemia (αT) and β-thalassemia (βT). In this study, we aimed to distinguish between these diseases in a distinct population of young men using a specific index.

Patients and Methods

We retrospectively reviewed the laboratory data of young men with microcytic anemia. The clinical, characteristic and laboratory data, including complete blood cell counts, serum ferritin and hemoglobin electrophoresis results, were collected; genomic DNA mutations were also evaluated. Based on these data, ten discrimination indices were used to differentiate thalassemia from IDA. The sensitivity, specificity, positive and negative predictive values, Youden’s index and receiver operating characteristic (ROC) curves were also calculated.

Results

A total of 877 patients (92 patients with IDA, 332 with αT and 453 with βT) were enrolled; the Shine and Lal (S&L) formula was the best method with which to discriminate IDA from thalassemia (100% sensitivity, 91% specificity). The new cut-off values were evaluated, and the approaches used in our study cohort, particularly the Green & King (G&K) formula, significantly increased the accuracies of red cell distribution width-containing indices (cut-off value: 58.66; 89.62% sensitivity and 96.2% specificity; AUC: 0.9716). In addition, when applied properly, these indices could differentiate IDA patients from αT patients, especially Huber-Herklotz index (HH).

Conclusions

The sensitivity and specificity differed among ethnic and age groups. We concluded that when using the original cut-off value, the S&L formula was the best discriminating index for differentiating between IDA and thalassemia in young Asian men. However, when using the G&K formula, the newly obtained cut-off value must be applied to increase accuracy based on the results from our cohort.

A novel promoter mutation (HBB: c.-75G>T) was identified as a cause of β(+)-thalassemia

We report a novel β-globin gene promoter mutation in a Chinese family identified using fluorescence resolution melting curve analysis and gene sequencing. The proband, who showed the phenotype of β-thalassemia intermedia (β-TI), was found to be a compound heterozygote for the novel mutation -25 (G>T) (HBB: c.-75G>T) and a codon 17 (HBB: c.52A>T) mutation. Moreover, conservation analysis using phyloP and phastCons indicated that the mutated base in the proband was conserved. This novel point mutation on the β-globin gene is in close proximity to the conserved ATAA sequence located at position -25 relative to the mRNA Cap site. We performed a further comparative analysis of the clinical phenotypes and hematological parameters in this pedigree and found that the father was a carrier of the novel point mutation and showed low levels of hemoglobin (Hb), mean corpuscular volume (MCV) and mean corpuscular Hb (MCH). Thus, the available evidence suggests that this novel mutation, -25, results in β(+)-thalassemia (β(+)-thal).

Hemoglobinopathies and sleep--The road less traveled

Sickle cell disease and thalassemia are common hereditary blood disorders associated with increased systemic inflammation, tissue hypoxia, endothelial dysfunction and end-organ damage, the latter accounting for the substantial morbidity and abbreviated lifespan associated with these conditions. Sleep perturbations in general, and sleep-disordered breathing in particular are also highly prevalent conditions and the mechanisms underlying their widespread end-organ morbidities markedly and intriguingly overlap with the very same pathways implicated in the hemoglobinopathies. However, little attention has been given to date to the potential contributing role of sleep disorders to sickle cell disease manifestations. Here, we comprehensively review the pathophysiological mechanisms and clinical manifestations linking disturbed sleep and hemoglobinopathies, with special emphasis on sickle cell disease. In addition to a broad summary of the available evidence, we identify many of the research gaps that require attention and future investigation, and provide the scientific contextual setting that should enable opportunities to investigate the intertwined pathophysiological mechanisms and clinical outcomes of sleep disorders and hemoglobinopathies.

Extracellular vesicles in hematological disorders

Extracellular vesicles (EVs), comprised of exosomes, microparticles, apoptotic bodies, and other microvesicles, are shed from a variety of cells upon cell activation or apoptosis. EVs promote clot formation, mediate pro-inflammatory processes, transfer proteins and miRNA to cells, and induce cell signaling that regulates cell differentiation, proliferation, migration, invasion, and apoptosis. This paper will review the contribution of EVs in hematological disorders, including hemoglobinopathies (sickle cell disease, thalassemia), paroxysmal nocturnal hemoglobinuria, and hematological malignancies (lymphomas, myelomas, and acute and chronic leukemias).