ß-Thalassemia minor & renal tubular dysfunction: is there any association?

OBJECTIVE: Beta(ß)-thalassemia is one of the most common hereditary hematologic disorders. Patients with thalassemia minor (TM) are often asymptomatic and the rate of renal dysfunction is unknown in these patients. Due to the high prevalence of renal dysfunction in Iran, the current study aimed to determine renal tubular dysfunction in patients with beta-TM. METHODS: In this case-control study, 40 patients with TM and 20 healthy subjects were enrolled and urinary and blood biochemical analysis was done on their samples. Renal tubular function indices were determined and compared in both groups. Data was analyzed by SPSS software, version 20.0. RESULTS: The fraction excretion (FE) of uric acid was 8.31 ± 3.98% in the case and 6.2 ± 34.71% in the control group (p = 0.048). Also, FE of potassium was significantly higher in patients with TM (3.22 ± 3.13 vs. 1.91 ± 0.81; p = 0.036). The mean Plasma NGAL level was 133.78 ± 120.28 ng/mL in patients with thalassemia and 84.55 ± 45.50 ng/mL in the control group (p = 0.083). At least one parameter of tubular dysfunction was found in 45% of patients with thalassemia. CONCLUSION: Based on the results of this study, the prevalence of tubular dysfunction in beta-thalassemia minor patients is high. Due to the lack of knowledge of patients about this disorder, periodic evaluation of renal function in TM patients can prevent renal failure by early diagnosis.

Molecular analysis of alpha- and beta-thalassemia in Meizhou region and comparison of gene mutation spectrum with different regions of southern China.

BACKGROUND: Thalassemia is a group of inherited autosomal recessive hemolytic anemia disease caused by reduced or absent synthesis of globin chain/chains of hemoglobin. Only few studies showed the molecular characterization of α- and ß-thalassemia in Meizhou city of China. METHODS: A total of 22,401 individuals were collected; hematological and hemoglobin electrophoresis analysis and thalassemia genetic testing were performed. RESULTS: Eleven thousand and thirty (49.24%) cases with microcytosis (mean corpuscular volume (MCV) < 82 fl), 11,074 (49.44%) cases with hypochromia (mean corpuscular Hb (MCH) < 27 pg) in 22,401 subjects, 11,085 cases with abnormal hemoglobin results were identified in subjects aged ≥6 months. 7,322 (32.69%) subjects harbored thalassemia mutations, including 4,841 (21.61%) subjects with α-thalassemia, 2,237 (9.99%) with ß-thalassemia, and 244 (1.09%) with α-thalassemia combined ß-thalassemia. 18 genotypes of α-thalassemia mutations and 27 genotypes of ß-thalassemia mutations were characterized. The most frequent α gene mutation was --SEA (64.69%), followed by -α3.7 (19.93%), -α4.2 (7.73%), αCS α (3.97%), and αWS α (2.83%). The six most common ß-thalassemia mutations were IVS-II-654 (C>T) (39.79%), CD41-42 (-TCTT) (33.02%), -28 (A>G) (10.38%), CD17 (A>T) (9.08%), CD27-28 (+C) (2.14%), and CD26 (G>A) (2.02%). In addition, MCV and MCH were sensitive markers for α- and ß-thalassemia except for -α3.7 /αα, -α4.2 /αα, αCS α/αα, αWS α/αα, and ßCap+40-43 /ßN . CONCLUSIONS: The --SEA , -α3.7 , and -α4.2 deletions were the main mutations of α-thalassemia, while IVS-II-654 (C>T), CD41-42 (-TCTT), -28 (A>G), and CD17 (A>T) mutations of ß-thalassemia in Meizhou. There were some differences in thalassemia mutation frequencies in Meizhou city from other populations in China.

Current status of beta-thalassemia and its treatment strategies.

BACKGROUND: Thalassemia is an inherited hematological disorder categorized by a decrease or absence of one or more of the globin chains synthesis. Beta-thalassemia is caused by one or more mutations in the beta-globin gene. The absence or reduced amount of beta-globin chains causes ineffective erythropoiesis which leads to anemia. METHODS: Beta-thalassemia has been further divided into three main forms: thalassemia major, intermedia, and minor/silent carrier. A more severe form among these is thalassemia major in which individuals depend upon blood transfusion for survival. The high level of iron deposition occurs due to regular blood transfusion therapy. RESULTS: Overloaded iron raises the synthesis of reactive oxygen species (ROS) that are noxious and prompting the injury to the hepatic, endocrine, and vascular system. Thalassemia can be analyzed and diagnosed via prenatal testing (genetic testing of amniotic fluid), blood smear, complete blood count, and DNA analysis (genetic testing). Treatment of thalassemia intermediate is symptomatic; however; it can also be accomplished by folic supplementation and splenectomy. CONCLUSION: Thalassemia major can be cured through regular transfusion of blood, transplantation of bone marrow, iron chelation management, hematopoietic stem cell transplantation, stimulation of fetal hemoglobin production, and gene therapy.

Clinical utility of Abbott Alinity hq extended red blood cell parameters in differentiating ß-thalassemia trait and iron deficiency anemia.

INTRODUCTION: The objective of the study was to evaluate the performance of the Abbott Alinity hq advanced multi angle polarized scatter separation (MAPSSTM )-based optical RBC technology, for the differentiation between iron deficiency anemia (IDA) and ß-thalassemia carrier status. METHODS: Four hundred and sixty-four samples were analyzed. 228 were healthy controls, 30 were ß-thalassemia carriers, and 40 were IDA. Receiver operating characteristics analysis evaluated the performance of red cell parameters and mathematical formulas. RESULTS: RBC concentration was the most efficient discriminant (area under the curve; AUC of 0.963, Youden Index of 0.88) followed by red blood cell distribution width in size distribution (AUC of 0.960 and YI of 0.86), and red blood cell distribution width coefficient of variation (AUC of 0.924, and YI of 0.74). The absolute reticulocyte concentration showed good diagnostic efficiency, with AUC of 0.808. Hemoglobin distribution width, the %CV of directly measured cellular hemoglobin concentration, and CHCr, the average hemoglobin concentration of reticulocytes have emerged as novel discriminating parameters, with AUC of 0.749 and 0.785, respectively. The England and Fraser index was the best discriminating mathematical formula based on Youden Index of 0.91. The Ricerca, red blood cell distribution width index, Green and King, and Mentzner Index formulas also showed strong discriminative power. The Shine and Lal index, together with the recent mathematical formula M/H, (ratio of percent microcytic and hypochromic red blood cells) demonstrated moderate performance with AUC of 0.796 and 0.740, respectively. CONCLUSION: Extended red cell analysis delivered by the advanced optical technology on the Alinity hq hematology analyzer has efficient diagnostic utility in the initial discrimination of the two most common microcytic anemias: IDA and ß-thalassemia trait.

Pleckstrin-2 is essential for erythropoiesis in ß-thalassemic mice, reducing apoptosis and enhancing enucleation.

Erythropoiesis involves complex interrelated molecular signals influencing cell survival, differentiation, and enucleation. Diseases associated with ineffective erythropoiesis, such as ß-thalassemias, exhibit erythroid expansion and defective enucleation. Clear mechanistic determinants of what make erythropoiesis effective are lacking. We previously demonstrated that exogenous transferrin ameliorates ineffective erythropoiesis in ß-thalassemic mice. In the current work, we utilize transferrin treatment to elucidate a molecular signature of ineffective erythropoiesis in ß-thalassemia. We hypothesize that compensatory mechanisms are required in ß-thalassemic erythropoiesis to prevent apoptosis and enhance enucleation. We identify pleckstrin-2-a STAT5-dependent lipid binding protein downstream of erythropoietin-as an important regulatory node. We demonstrate that partial loss of pleckstrin-2 leads to worsening ineffective erythropoiesis and pleckstrin-2 knockout leads to embryonic lethality in ß-thalassemic mice. In addition, the membrane-associated active form of pleckstrin-2 occurs at an earlier stage during ß-thalassemic erythropoiesis. Furthermore, membrane-associated activated pleckstrin-2 decreases cofilin mitochondrial localization in ß-thalassemic erythroblasts and pleckstrin-2 knockdown in vitro induces cofilin-mediated apoptosis in ß-thalassemic erythroblasts. Lastly, pleckstrin-2 enhances enucleation by interacting with and activating RacGTPases in ß-thalassemic erythroblasts. This data elucidates the important compensatory role of pleckstrin-2 in ß-thalassemia and provides support for the development of targeted therapeutics in diseases of ineffective erythropoiesis.

Identification and Development of a High-Risk District Model in the Prevention of ß-Thalassemia in Telangana State, India.

The burden of ß-thalassemia (ß-thal) is largely underestimated in India with a carrier frequency of 3.0-4.0% in general, whereas highly stratified frequencies of up to 17.0% are reported in local endogamous subpopulations. We have no idea whether ß-thal carrier frequencies or ß-thal major (ß-TM) births are increasing or decreasing in the population. The cross-sectional nature of all carrier screening programs including large-scale task force and micro level, lack of registration of ß-TM births and mechanism to modulate knowledge, awareness programs in a long-term perspective, all preempt impact assessment of preventive programs. During the implementation of a Telangana State Government-sponsored program on 'Micro profiling of ß-thalassemia mutations in Telangana,' we documented extensive in-depth demographic information on each ß-TM child of the study sample that included age-sex distributions, parental and grand-parental ethnic affiliations (local endogamous group level), birth places, marital migrations, endogamy and consanguinity to identify high-risk districts as ethno-geographic regions. In Telangana State, we found ß-thal is widely prevalent in 31 districts and 48 local endogamous subpopulations. The present study provided a method of identification of four 'high-risk districts' and developed a district model for prevention on high priority in Telangana State. The model has the advantage of impact-assessment of all preventive programs in the district.

Implications of Population Screening for Thalassemias and Hemoglobinopathies in Rural Areas of West Bengal, India: Report of a 10-Year Study of 287,258 Cases.

Thalassemia and hemoglobinopathies are the most common cause of high morbidity and mortality in India. Detection of carriers and premarital counseling play an important role in preventing the birth of a thalassemic child. The present study aimed to detect large numbers of asymptomatic carriers in rural areas of West Bengal, India. The present cross-sectional study was conducted over a period of 10 years. Thalassemia awareness programs and detection camps were organized at the community level. After signed written consent was obtained, the collected blood samples were subjected to a complete blood count (CBC) in an automated blood cell counter and then analyzed by high performance liquid chromatography (HPLC); in difficult cases, samples were sent to the reference laboratory for molecular characterization. Out of 287,258 samples collected, 32,921 (11.46%) cases revealed abnormal hemoglobins (Hbs); of these, 31,782 (11.06%) carried heterozygous states (carriers/traits), and the remainder were either homozygous or compound heterozygous for different hemoglobinopathies. Two common variants were revealed in the study, namely ß-thalassemia (ß-thal) (7.23%) and Hb E [ß26(B8)Glu→Lys, HBB: c.79G>A] (2.77%) traits. Among homozygous or compound heterozygous states, Hb E/ß-thal (0.14%) and ß-thal major (ß-TM) (0.12%) were predominant. In rural areas of West Bengal, the most common Hb variants detected were ß-thal and Hb E traits. In view of the high prevalence of hemoglobinopathies in this region, routine premarital screening and genetic counseling should be emphasized and encouraged to prevent the birth of a thalassemic child, and thus curtailing the burden on families and the health economy.

Changing patterns in the epidemiology of ß-thalassemia.

ß-thalassemia major is an inherited hemoglobinopathy that requires lifelong red blood cell transfusions and iron chelation therapy to prevent complications due to iron overload. Traditionally, ß-thalassemia has been more common in certain regions of the world such as the Mediterranean, Middle East, and Southeast Asia. However, the prevalence of ß-thalassemia is increasing in other regions, including Northern Europe and North America, primarily due to migration. This review summarizes the available data on the changing incidence and prevalence of ß-thalassemia as well as factors influencing disease frequency. The data suggest that the epidemiology of ß-thalassemia is changing: Migration has increased the prevalence of the disease in regions traditionally believed to have a low prevalence, while, at the same time, prevention and screening programs in endemic regions have reduced the number of affected individuals. Various approaches to prevention and screening have been used. Region-specific prevention and treatment programs, customized to align with local healthcare resources and cultural values, have been effective in identifying patients and carriers and providing information and care. Significant challenges remain in universally implementing these programs.

Hematological Characteristics of ß-Globin Gene Mutation -50 (G>A) (HBB: c.-100G>A) Carriers in Mainland China.

The -50 (G>A) (HBB: c.-100G>A) mutation was first reported as a ß-thalassemia (ß-thal) allele in a Chinese family. However, the hematological features of carriers with this variant are not available. In this study, we present the hematological data associated with -50 (G>A) to determine its phenotype. During a 4-year period, eight simple heterozygotes and three double heterozygotes for the -50 mutation and α-thalassemia (α-thal) were included. The simple heterozygotes had normal hematological parameters. The double heterozygotes had the hematological findings of simple α-thal heterozygotes. Two subjects with a compound heterozygosity for -50 and ß-thal were also found, and both had typical hematological parameters of ß-thal trait. Therefore, we present evidence that -50 (G>A) is likely a silent ß-thal allele. Compound heterozygotes for -50/ß-thal had no phenotype of severe ß-thal. This information might be helpful in genetic counseling for couples in thalassemia high-prevalence areas.

Red cell alloimmunization in transfusion-dependent and transfusion-independent beta thalassemia: A review from the Eastern Mediterranean Region (EMRO).

BACKGROUND: ß-Thalassemia is considered one of the common hemoglobin disorders in the Arabian Peninsula. Red blood cell (RBC) transfusion is a crucial component of the management of transfusion-dependent ß-Thalassemia patients. Patients with Thalassemia Intermedia (TI), also known as non-transfusion dependent ß-thalassemia, have a wide clinical presentation and variable transfusion dependence. Rates of RBC alloimmunization and its risk factors in transfusion-dependent ß-thalassemia patients varied between different reports. Risk of alloimmunization is higher in TI patients. MATERIAL AND METHODS: A literature review on existing reports on alloimmunization rates and risk factors in transfusion dependent and non-transfusion dependent ß-thalassemia in the Eastern Mediterranean region was performed. RESULTS: A total of 17 publications were found. Reported rates of alloimmunization among transfusion-dependent ß-Thalassemia patients ranged between 2.87 and 30 % and between 6.8 and 19.5 % among TI patients. Most centers utilize ABO and RhD matched RBCs. The most common antibodies described are anti-K and anti-E. The risk factors described included age at onset of transfusion, gender, history of splenectomy, duration of transfusion and number of units transfused. Rate of autoantibody formation ranged between 0.1 and 45 %. CONCLUSION: Our review showed variable alloimmunization rates and risk factors in thalassemia patients and scant data on TI patients. The commonest antibodies are anti-K and anti-E. Further studies are required in addressing the rate of alloimmunization, cross-match requirements and role of genotyping in this group of patients. Transfusion support of patients with thalassemia necessitates the availability of blood bank facilities and specialized expertise.

Genotype-phenotype association analysis identifies the role of α globin genes in modulating disease severity of ß thalassaemia intermedia in Sri Lanka.

ß thalassaemia intermedia (ßTI) are a heterogeneous group of disorders known to be extremely phenotypically diverse. This group is more complex to manage as no definitive treatment guidelines exist unlike for ß thalassaemia major (ßTM). There are only a few studies looking at genotype phenotype associations of ßTI outside the Mediterranean region. The reasons for the diverse clinical phenotype in ßTI are unknown. We categorized fifty Sri Lankan patients diagnosed with ßTI as mild, moderate or severe according to published criteria. DNA samples were genotyped for ß thalassaemia mutations, α globin genotype and copy number and known genetic modifiers of haemoglobin F production. There were 26/50 (52.0%) in mild group and 12/50 (24.0%) each in moderate and sever categories. 18/26 (69.2%) classified as mild were ß heterozygotes and 17/18 (94.4%) had excess α globin genes. 11/12 (91.6%) classified as moderate were ß heterozygotes and 8/11 (72.2%) had excess α globin genes. In contrast, 8/12 (66.7%) classified as severe were ß homozygotes and 7/8(87.5%) had α globin gene deletions. In Sri Lanka, co-inheritance of either excess α globin genes in ß thalassaemia heterozygotes or α globin gene deletions in ß thalassaemia homozygotes is a significant factor in modulating disease severity.

A case of post-splenectomy transfusion-dependent homozygous beta-thalassemia major complicated with myocardial siderosis and osteoporosis and usage of iron-chelating therapy with deferiprone in pregnancy.

Beta-thalassemia major is a subtype component of hemoglobinopathies; autosomal recessive disorders complicated with anemia that affect at least 50,000 babies each year. It contributes to problems in reproductive entities such as infertility due to iron deposition in the endocrine organs, which leads to malfunction of the hypothalamus-pituitary axis. Due to this, there have been very few pregnancies discovered and reported with this type of condition as they usually required an ovulation-induction agent with assisted reproductive technique to achieved pregnancy. We report a successful spontaneous pregnancy in a woman with beta-thalassemia major who underwent splenectomy with lifelong transfusion-dependence complicated with myocardial siderosis and osteoporosis. The close monitoring and regular blood transfusion are a core of successful support to this type of pregnancy. The unintentional consumption of Fosamax, hydroxyurea and deferiprone (Ferriprox) up till 20 weeks of gestation did not show any adverse effects on fetal well-being. As expected, this pregnancy ended with the preterm delivery via cesarean section due to intrauterine growth restriction with oligohydramnios, and currently, this child is thriving. We concluded that pregnancy is not a contraindication in beta-thalassemia major; complex individual care is needed to achieve a safe outcome for the mother.

The first case of severe acute hemolytic transfusion reaction caused by anti-Sc2.

BACKGROUND: Alloantibodies to the low-frequency antigen Scianna-2 (Sc2) have been implicated in cases of hemolytic disease of the fetus and newborn but never in hemolytic transfusion reactions (HTRs); thus, the clinical significance of anti-Sc2 has yet to be fully addressed. STUDY DESIGN AND METHODS: A 26-year-old woman with thalassemia presented rigors, fever, nausea, abdominal pain, and hemolytic biochemistry after exposure to 75 mL of plasma-reduced red blood cells (RBCs). The RBC unit was issued by electronic crossmatch but was 3+ incompatible on recrossmatch by gel indirect antiglobulin test (IAT). The patient had anti-Sc2 previously identified, but considered to be clinically insignificant. The transfusion history was reviewed and a monocyte monolayer assay (MMA) was performed. RESULTS: The patient was investigated for a RBC reaction 9 years prior, when she developed symptoms of HTR. The RBC unit was crossmatched by immediate spin due to consistent screen negativity. Full crossmatch found the RBC 1+ incompatible by gel IAT with both pre/post samples, while direct antiglobulin test was negative (pre) and 1+ immunoglobulin G positive (post). The antibody remained unidentified and she was committed to gel IAT crossmatch. Two-years later, the specificity to Sc2 was deduced when one RBC unit was found 3+ incompatible. Finally, the transfusion reaction reported herein occurred when she received by happenstance RBCs from the same donor who was associated with the remote reaction 9 years earlier. MMA yielded highly positive phagocytic indices only for Sc2+ RBCs, including the donor's RBCs that triggered the severe HTR. CONCLUSION: This is the first case of HTR caused by anti-Sc2 confirmed by clinical findings and MMA.

The changing epidemiology of Ebstein's anomaly and its relationship with maternal mental health conditions: a European registry-based study.

OBJECTIVES: The aim of this study was to describe the epidemiology of Ebstein's anomaly in Europe and its association with maternal health and medication exposure during pregnancy. DESIGN: We carried out a descriptive epidemiological analysis of population-based data. SETTING: We included data from 15 European Surveillance of Congenital Anomalies Congenital Anomaly Registries in 12 European countries, with a population of 5.6 million births during 1982-2011. Participants Cases included live births, fetal deaths from 20 weeks gestation, and terminations of pregnancy for fetal anomaly. Main outcome measures We estimated total prevalence per 10,000 births. Odds ratios for exposure to maternal illnesses/medications in the first trimester of pregnancy were calculated by comparing Ebstein's anomaly cases with cardiac and non-cardiac malformed controls, excluding cases with genetic syndromes and adjusting for time period and country. RESULTS: In total, 264 Ebstein's anomaly cases were recorded; 81% were live births, 2% of which were diagnosed after the 1st year of life; 54% of cases with Ebstein's anomaly or a co-existing congenital anomaly were prenatally diagnosed. Total prevalence rose over time from 0.29 (95% confidence interval (CI) 0.20-0.41) to 0.48 (95% CI 0.40-0.57) (p<0.01). In all, nine cases were exposed to maternal mental health conditions/medications (adjusted odds ratio (adjOR) 2.64, 95% CI 1.33-5.21) compared with cardiac controls. Cases were more likely to be exposed to maternal ß-thalassemia (adjOR 10.5, 95% CI 3.13-35.3, n=3) and haemorrhage in early pregnancy (adjOR 1.77, 95% CI 0.93-3.38, n=11) compared with cardiac controls. CONCLUSIONS: The increasing prevalence of Ebstein's anomaly may be related to better and earlier diagnosis. Our data suggest that Ebstein's anomaly is associated with maternal mental health problems generally rather than lithium or benzodiazepines specifically; therefore, changing or stopping medications may not be preventative. We found new associations requiring confirmation.

Mitophagy is increased during erythroid differentiation in ß-thalassemia.

Mitophagy is a selective degradation of mitochondria, which also plays a critical role in hematopoiesis. However, it is unclear what role, if any, this process plays in the pathogenesis of ß-thalassemia. To determine the role of mitophagy in ß-thalassemia, CD34+ hematopoietic progenitor cells (HPCs) were isolated from peripheral blood of ß-thalassemia patients and healthy controls and differentiated into erythrocytes. We found that the ratio of mitochondrial membrane depolarization was significantly increased, and that mitochondria co-localize with lysosomes at a higher level in ß-thalassemia compared with control. Furthermore, the expression of LC3-II and Nix, as well as degradation of p62, in ß-thalassemia was higher than in the control. In sum, our data suggest that selective mitophagy is enhanced during erythrocyte differentiation in ß-thalassemia.

Current trends of seroprevalence of transfusion transmitted infections in Pakistani ß-thalassaemic patients.

BACKGROUND: Though regular blood transfusion improves the survival, it carries the unavoidable risk of transfusion transmitted infections (TTI) in ß-thalassaemic patients. Owing to the lack of uniformity in blood screening practices in Pakistan, TTI is still a major challenge. OBJECTIVES: To study the current trends of TTI in regularly transfused ß-thalassaemics and their correlation with age, number of transfusions, hematological and biochemical markers. METHODS: We carried out a prospective case-control study. 100 ß-thalassemic patients and 200 healthy donors were recruited from June 2011 to June 2014. HCV antibodies, Hepatitis B surface antigen and human immunodeficiency virus antibodies (I & II) were evaluated. Complete blood counts, LFTs and serum ferritin were tested on all patients. RESULTS: Mean age of patients and controls was 11.18±5.07 and 20.5±1.87 years respectively. In patients, 54% and 46% were males and females respectively. Anti-HCV antibody and HbsAg were positive in 27% versus 3% and 3% versus 2% in patients and controls respectively. None of the patients and controls was HIV reactive. Seropositivity of Anti-HCV was significantly higher in patients than that of controls (P<0.001). Anti-HCV positively correlated with age above 10 years, numbers of transfusions (≥150 units), high serum ferritin, elevated ALT and alkaline phosphatase (P<0.001). CONCLUSIONS: Over the decade, TTI magnitude has significantly reduced, but hepatitis C is still a main hazard. Further preventive measures including nucleic acid testing, voluntary donation and stringent donor selection will be required for reducing TTI in ß-thalassaemics.

ß-thalassemias: paradigmatic diseases for scientific discoveries and development of innovative therapies.

ß-thalassemias are monogenic disorders characterized by defective synthesis of the ß-globin chain, one of the major components of adult hemoglobin. A large number of mutations in the ß-globin gene or its regulatory elements have been associated with ß-thalassemias. Due to the complexity of the regulation of the ß-globin gene and the role of red cells in many physiological processes, patients can manifest a large spectrum of phenotypes, and clinical requirements vary from patient to patient. It is important to consider the major differences in the light of potential novel therapeutics. This review summarizes the main discoveries and mechanisms associated with the synthesis of ß-globin and abnormal erythropoiesis, as well as current and novel therapies.