Newborn screening for hemoglobinopathies in California

Global Trends on β-Thalassemia Research Over 10 Years: A Bibliometric Analysis

Purpose

Thalassemia, an inherited quantitative globin disorder, is the most prevalent monogenic disease globally. While severe alpha thalassemia results in intrauterine death, β-thalassemia manifests during childhood due to the "second conversion of hemoglobin", garnering increased attention in recent decades.

Methods

In this study, a bibliometric analysis was conducted of thalassemia articles published in the Web of Science Core Collection database between 2013 and 2023 to establish a comprehensive overview and to identify emerging trends. A total of 5655 studies published between 2013 and 2023 were systematically retrieved, and annual publications demonstrated a steady increase, maintaining a high level over the past decade.

Results

The United States contributed the highest number of publications, followed by China. Notably, the journal Blood emerged as the leading authority in β-thalassemia research. Analysis of research hotspots revealed that the pathogenesis of β-thalassemia is primarily linked to iron overload, anemia, gene mutations, and ineffective erythropoiesis. Furthermore, recent studies focusing on gene editing therapies present promising avenues for future investigation.

Conclusion

These findings grasp the research status of β-thalassemia and shed new light on future research frontiers.

A multiplexed, allele-specific recombinase polymerase amplification assay with lateral flow readout for sickle cell disease detection

Isothermal nucleic acid amplification tests have the potential to improve disease diagnosis at the point of care, but it remains challenging to develop multiplexed tests that can detect ≥3 targets or to detect point mutations that may cause disease. These capabilities are critical to enabling informed clinical decision-making for many applications, such as sickle cell disease (SCD). To address this, we describe the development of a multiplexed allele-specific recombinase polymerase amplification (RPA) assay with lateral flow readout. We first characterize the specificity of RPA using primer design strategies employed in PCR to achieve point mutation detection, and demonstrate the utility of these strategies in achieving selective isothermal amplification and detection of genomic DNA encoding for the healthy βA globin allele, or genomic DNA containing point mutations encoding for pathologic βS and βC globin alleles, which are responsible for most sickle cell disorders. We then optimize reaction conditions to achieve multiplexed amplification and identification of the three alleles in a single reaction. Finally, we perform a small pilot study with 20 extracted genomic DNA samples from SCD patients and healthy volunteers - of the 13 samples with valid results, the assay demonstrated 100% sensitivity and 100% specificity for detecting pathologic alleles, and an overall accuracy of 92.3% for genotype prediction. This multiplexed assay is rapid, minimally instrumented, and when combined with point-of-care sample preparation, could enable DNA-based diagnosis of SCD in low-resource settings. The strategies reported here could be applied to other challenges, such as detection of mutations that confer drug resistance.

Αlpha-thalassemia: A practical overview

α-Thalassemia is an inherited blood disorder characterized by decreased synthesis of α-globin chains that results in an imbalance of α and β globin and thus varying degrees of ineffective erythropoiesis, decreased red blood cell (RBC) survival, chronic hemolytic anemia, and subsequent comorbidities. Clinical presentation varies depending on the genotype, ranging from a silent or mild carrier state to severe, transfusion-dependent or lethal disease. Management of patients with α-thalassemia is primarily supportive, addressing either symptoms (eg, RBC transfusions for anemia), complications of the disease, or its transfusion-dependence (eg, chelation therapy for iron overload). Several novel therapies are also in development, including curative gene manipulation techniques and disease modifying agents that target ineffective erythropoiesis and chronic hemolytic anemia. This review of α-thalassemia and its various manifestations provides practical information for clinicians who practice beyond those regions where it is found with high frequency.

Algorithm of differential diagnosis of anemia involving laboratory medicine specialists to advance diagnostic excellence

OBJECTIVES

Anemia is a severe global public health issue. Testing practices for anemia suggest overuse of screening laboratory tests and misinterpretation of studies even in "easy-to-diagnose" underlying causes, leading to late diagnoses and missed treatment opportunities. We aimed to develop a complete and efficient algorithm for clinical pathologists and laboratory medicine physicians for the differential diagnosis of anemia.

METHODS

Comprehensive literature search encompassing original articles, studies, reviews, gold standard books, and other evidence.

RESULTS

We created a complex algorithm, primarily for clinical pathology/laboratory use, that explores all major and several rare causes of anemia in an efficient and evidence-based manner. The algorithm includes gold-standard diagnostic laboratory tests available in most clinical laboratories and indices that can be easily calculated to provide an evidence-based differential diagnosis of anemia.

CONCLUSIONS

The diagnostic strategy combines previously available diagnostic tests and protocols in an efficient order. Clinical pathologists following the algorithm can independently provide valuable diagnostic support for healthcare providers. Clinical pathologists providing complete differential diagnostic services with the proposed algorithm may create an opportunity for an advanced diagnostic service that supports diagnostic excellence and helps patients receive a timely diagnosis and early treatment opportunities.

Mode of delivery preference in prenatal genetic counseling between English- and Spanish-speaking patients at two US medical institutions

Although Hispanic individuals are at an increased risk for various genetic conditions, they have lower uptake of genetic counseling and genetic testing. Virtual appointments have many advantages that may help Spanish-speaking patients access genetic services more readily. Despite these benefits, there are limitations that may make them less attractive options for these individuals. This study aimed to determine if satisfaction with genetic counseling or mode of delivery preference differs between English- and Spanish-speaking individuals who have had a virtual prenatal genetic counseling session. Participants were recruited from prenatal genetic counseling clinics at Indiana University Health and Eskenazi Hospital. A REDCap survey was sent to all eligible participants. Survey questions included mode of delivery preference for future genetic counseling sessions (virtual versus in-person), the validated Genetic Counseling Satisfaction Scale, and questions inquiring about the importance of various factors affecting mode of delivery preference. Spanish-speaking individuals preferred future visits to be in-person, while English-speaking individuals preferred future visits to be virtual (Fisher's exact p = 0.003). Several factors were associated with these preferences, including waiting time, ability to leave/take off work for an appointment, length of session, childcare arrangements, and people attending the appointment (all p < 0.05). Both language groups reported similar mean satisfaction with the genetic counseling provided during their previous virtual appointments (p = 0.51). This study found that certain aspects of virtual genetic counseling appointments make them less appealing to Spanish-speaking individuals. Making virtual genetic counseling appointments more appealing while continuing to offer in-person appointments may help Spanish-speaking individuals receive necessary genetics services. Continued research into disparities and barriers to telemedicine for Spanish-speaking patients is necessary to increase access to this service delivery model for genetic counseling.

Performance of single-gene noninvasive prenatal testing for autosomal recessive conditions in a general population setting

OBJECTIVE

Carrier screening with reflex to single-gene noninvasive prenatal testing (sgNIPT) is an alternative approach for identifying pregnancies at risk for inherited autosomal recessive conditions without the need for a sample from the reproductive partner. This study is the largest clinical validation of this approach in a general population setting.

METHODS

The clinical performance of carrier screening with reflex to sgNIPT for cystic fibrosis, spinal muscular atrophy, alpha thalassemias, and beta hemoglobinopathies was assessed by collecting pregnancy outcome data on patients who underwent this testing and comparing the neonatal outcome to the assay-predicted fetal risk.

RESULTS

Of 42,067 pregnant individuals who underwent screening, 7538 carriers (17.9%) had reflex sgNIPT, and neonatal or fetal outcomes were obtained for 528 cases, including 25 affected pregnancies. Outcomes demonstrated high concordance with sgNIPT, for example, all pregnancies with 9 in 10 personalized fetal risk results were affected (positive predictive value (PPV) of 100% for the sub-group) and the sgNIPT assay showed a sensitivity of 96.0% (95% CI: 79.65%-99.90%), specificity of 95.2% (95% CI: 92.98%-96.92%), average PPV of 50.0% (95% CI: 35.23%-64.77%), and negative predictive value (NPV) of 99.8% (95% CI: 98.84%-99.99%). The end-to-end performance of carrier screening with reflex to sgNIPT was calculated to have a sensitivity of 92.4% and specificity of 99.9%, which are unaffected by partner carrier screening or misattributed paternity unlike a traditional carrier screening workflow, which has a 35% sensitivity and a maximum of 25% PPV (1 in 4) in a real-life setting.

CONCLUSION

This study builds upon earlier findings to confirm that carrier testing with reflex to sgNIPT is highly accurate for general population screening. Given this high accuracy and an NPV of 99.8%, this workflow should be considered as an option for most of the general pregnant population. When the biological partner sample is unavailable, this workflow should be recommended as the first-line approach.

Creating an automated contemporaneous cohort in sickle cell anemia to predict survival after disease-modifying therapy

The Food and Drug Administration requires contemporaneous controls to compare clinical outcomes for participants receiving experimental gene therapy or gene editing clinical trials. However, developing a contemporaneous cohort of rare diseases requires multiple person-hours. In a single referral center for sickle cell disease, we tested the hypothesis that we could create an automated contemporaneous cohort of children and adults with sickle cell anemia (SCA) to predict mortality. Data were obtained between 1 January 2004 and 30 April 2021. We identified 419 individuals with SCA with consistent medical care defined as followed continuously for >0.5 years with no visit gaps >3.0 years. The median age was 10.2 years (IQR, 1-24 years), with a median follow-up of 7.4 years (IQR, 3.6-13.5 years) and 47 deaths. A total of 98% (274 of 277) of the children remained alive at 18 years of age, and 34.3% (94 of 274) of those children were followed into adulthood. For adults, the median age of survival was 49.3 years. Treatment groups were mutually exclusive and in a hierarchical order: hematopoietic stem cell transplant (n = 22)>regular blood transfusion for at least 2 years (n = 56)>hydroxyurea for at least 1 year (n = 243)>no disease-modifying therapy (n = 98). Compared to those receiving no disease-modifying treatment, those treated with hydroxyurea therapy had a significantly lower hazard of mortality (hazard ratio = 0.38; P = 0.016), but no statistical difference for those receiving regular blood transfusions compared to no disease-modifying therapy (hazard ratio = 0.71; P = 0.440). An automated contemporaneous SCA cohort can be generated to estimate mortality in children and adults with SCA.

Acceptance, Knowledge, and Experiences of Pediatric Hematologists in the Philippines on Newborn Screening for Hemoglobinopathies

Background

Hemoglobinopathies as a group is one of the most common conditions confirmed through the newborn screening (NBS) program of the Philippines. This led to the increased participation of pediatric hematologists in the NBS program.

Objective

The aim of the study was to assess newborn screening acceptance and knowledge of pediatric hematologists using an online questionnaire.

Methods

Members of the Philippine Society of Pediatric Hematology (PSPH), who are practicing pediatric hematologists in the Philippines, were invited to answer an online questionnaire.

Results

Sixty members of the PSPH (65.2%) answered the survey. All the respondents are familiar with the newborn screening program. Fifty-seven respondents (95 %) have already managed a case of hemoglobinopathy identified through the newborn screening program. Differences in the approach to management and level of confidence with diagnostic test result interpretation have been noted. General themes of their concerns include being unaware of the protocol, concerns on delays in confirmatory tests, request for guidelines on follow-up, and incongruence of results with clinical picture.

Conclusion

The information collected may be used to develop strategies to better equip our pediatric hematologists and assist the PSPH standardize management protocols for hemoglobinopathies.

Thalassaemia in China

Because of successful thalassaemia prevention programmes in resource-rich countries and it's huge population China now has the greatest number of new cases of thalassaemia globally as well as more people with thalassaemia than any other country. 30 million Chinese have thalassaemia-associated mutations and about 300,000 have thalassaemia major or intermedia requiring medical intervention. Over the past 2 decades there has been tremendous economic growth in China including per capita spending on health care. There is now nation-wide availability and partial or full insurance for prenatal genetic testing, RBC-transfusions, iron-chelating drugs and haematopoietic cell transplants. Prenatal screening and educational programmes have reduced the incidence of new cases. However, substantial challenges remain. For example, regional differences in access to medical care and unequal economic development require innovations to reduce the medical, financial and psychological burdens of Chinese with thalassaemia and their families. In this review we discuss success in preventing and treating thalassaemia in China highlighting remaining challenges. Our discussion has important implications for resource-poor geospaces challenged with preventing and treating thalassaemia.

Adherence to hydroxyurea and clinical outcomes among children with sickle cell anemia

OBJECTIVE

Hydroxyurea lowers the incidence of vaso-occlusive pain crises (VOC) and acute chest syndrome (ACS) among children with sickle cell anemia (SCA). Our objective was to assess the relationship between levels of adherence to hydroxyurea and clinical outcomes among children and adolescents with SCA.

METHODS

This retrospective cohort study included Medicaid data (2005-2012) from Florida, Illinois, Louisiana, Michigan, South Carolina, and Texas. The study population consisted of children 1-17 years old with SCA enrolled in Medicaid for 3 years. Among children that initiated hydroxyurea, the medication possession ratio (MPR) was calculated as the proportion of days covered by hydroxyurea. Six months after initiation of hydroxyurea, clinical outcomes were assessed through the end of the study period: numbers of VOC-related inpatient admissions and emergency department visits, and encounters for ACS. Multivariable Poisson models were used to predict outcomes by MPR quartile adjusting for previous healthcare utilization, state, and age.

RESULTS

Hydroxyurea was initiated by 515 children. The median MPR was 0.53 (interquartile range = 0.3-0.8). The annual median number of visits was 0.0 for ACS, 1.3 for VOC-related emergency department, and 1.4 for VOC-related inpatient admissions. For each outcome, the highest quartile of MPR had the lowest predicted count; this difference was significant for ACS visits when compared with the lowest quartile of MPR.

CONCLUSION

This study demonstrated a high level of adherence (>75%) was essential to achieve a lower incidence of common negative clinical outcomes. Further, moderate and severe hydroxyurea nonadherence may be more common than previously appreciated among children, emphasizing the importance of developing and testing innovative strategies to increase adherence.

The Clinical Phenotypes of Alpha Thalassemia

Clinical manifestations of α-thalassemia range from no symptoms to severe transfusion-dependent anemia. Alpha thalassemia trait is deletion of 1 to 2 α-globin genes, whereas α-thalassemia major (ATM; Barts hydrops fetalis) is the deletion all 4 α genes. All other genotypes of intermediate severity are categorized as HbH disease, a vastly heterogenous group. Clinical spectrum is classified as mild, moderate, and severe by symptoms and need for intervention. Anemia in prenatal period may be fatal without intrauterine transfusions. New therapies to modify HbH disease or provide cure for ATM are under development.

Sickle cell disease among Latinx in California

INTRODUCTION

After African Americans, Latinx are the second largest population affected by Sickle Cell Disease (SCD) in the U.S. However, research has largely ignored how this devastating rare blood disorder specifically affects Latinx nationwide.

METHODS

This study compared demographics, genotypes, primary insurance, and health care utilization among Latinx and non-Latinx Californians living with SCD, using data from the California SCD Data Collection Program (2016-2018) and newborn screening cases 2000-2017.

RESULTS

Stemming from 6,837 SCD patients, 501(7%) were Latinx. Latinx with SCD (Lx-SCD) were statistically significantly younger than non-Latinx (NLx-SCD) counterparts. Within both groups, females predominated, with 70% being insured by Medicaid. Mean Emergency Department encounters were statistically significantly lower among Lx-SCD adults.

DISCUSSION

Lx-SCD differ in age, genotype, and Emergency Department utilization, when compared to NLx-SCD counterparts in California. Latinx are now the largest racial and/or ethnic group in the US, and their presence in SCD population is expected to grow. Therefore, their specific demographic, genotypic, and health care utilization characteristics merit attention to inform policies and programs that will improve their health.

Survival and complications in patients with haemoglobin E thalassaemia in Sri Lanka: a prospective, longitudinal cohort study

BACKGROUND

Worldwide, haemoglobin E β-thalassaemia is the most common genotype of severe β-thalassaemia. The paucity of long-term data for this form of thalassaemia makes evidence-based management challenging. We did a long-term observational study to define factors associated with survival and complications in patients with haemoglobin E thalassaemia.

METHODS

In this prospective, longitudinal cohort study, we included all patients with haemoglobin E thalassaemia who attended the National Thalassaemia Centre in Kurunegala, Sri Lanka, between Jan 1, 1997, and Dec 31, 2001. Patients were assessed up to three times a year. Approaches to blood transfusions, splenectomy, and chelation therapy shifted during this period. Survival rates between groups were evaluated using Kaplan-Meier survival function estimate curves and Cox proportional hazards models were used to identify risk factors for mortality.

FINDINGS

109 patients (54 [50%] male; 55 [50%] female) were recruited and followed up for a median of 18 years (IQR 14-20). Median age at recruitment was 13 years (range 8-21). 32 (29%) patients died during follow-up. Median survival in all patients was 49 years (95% CI 45-not reached). Median survival was worse among male patients (hazard ratio [HR] 2·51, 95% CI 1·16-5·43), patients with a history of serious infections (adjusted HR 8·49, 2·90-24·84), and those with higher estimated body iron burdens as estimated by serum ferritin concentration (adjusted HR 1·03, 1·01-1·06 per 100 units). Splenectomy, while not associated with statistically significant increases in the risks of death or serious infections, ultimately did not eliminate a requirement for scheduled transfusions in 42 (58%) of 73 patients. Haemoglobin concentration less than or equal to 4·5 g/dL (vs concentration >4·5 g/dL), serum ferritin concentration more than 1300 μg/L (vs concentration ≤1300 μg/L), and liver iron concentration more than 5 mg/g dry weight of liver (vs concentration ≤5 mg/g) were associated with poorer survival.

INTERPRETATION

Patients with haemoglobin E thalassaemia often had complications and shortened survival compared with that reported in high-resource countries for thalassaemia major and for thalassaemia intermedia not involving an allele for haemoglobin E. Approaches to management in this disorder remain uncertain and prospective studies should evaluate if altered transfusion regimens, with improved control of body iron, can improve survival.

FUNDING

Wellcome Trust, Medical Research Council, US March of Dimes, Anthony Cerami and Ann Dunne Foundation for World Health, and Hemoglobal.

Diagnosis patterns of sickle cell disease in Ghana: a secondary analysis

BACKGROUND

Despite having the highest prevalence of sickle cell disease (SCD) in the world, no country in Sub-Saharan Africa has a universal screening program for the disease. We sought to capture the diagnosis patterns of SCD (age at SCD diagnosis, method of SCD diagnosis, and age of first pain crisis) in Accra, Ghana.

METHODS

We administered an in-person, voluntary survey to parents of offspring with SCD between 2009 and 2013 in Accra as a part of a larger study and conducted a secondary data analysis to determine diagnosis patterns. This was conducted at a single site: a large academic medical center in the region. Univariate analyses were performed on diagnosis patterns; bivariate analyses were conducted to determine whether patterns differed by participant's age (children: those < 18 years old whose parents completed a survey about them, compared to adults: those > = 18 years old whose parents completed a survey about them), or their disease severity based on SCD genotype. Pearson's chi-squared were calculated.

RESULTS

Data was collected on 354 unique participants from parents. Few were diagnosed via SCD testing in the newborn period. Only 44% were diagnosed with SCD by age four; 46% had experienced a pain crisis by the same age. Most (66%) were diagnosed during pain crisis, either in acute (49%) or primary care (17%) settings. Children were diagnosed with SCD at an earlier age (74% by four years old); among the adults, parents reflected that 30% were diagnosed by four years old (p < 0.001). Half with severe forms of SCD were diagnosed by age four, compared to 31% with mild forms of the disease (p = 0.009).

CONCLUSIONS

The lack of a robust newborn screening program for SCD in Accra, Ghana, leaves children at risk for disease complications and death. People in our sample were diagnosed with SCD in the acute care setting, and in their toddler or school-age years or thereafter, meaning they are likely being excluded from important preventive care. Understanding current SCD diagnosis patterns in the region can inform efforts to improve the timeliness of SCD diagnosis, and improve the mortality and morbidity caused by the disease in this high prevalence population.

The Evolving Role of Next-Generation Sequencing in Screening and Diagnosis of Hemoglobinopathies

During the last few years, next-generation sequencing (NGS) has undergone a rapid transition from a research setting to a clinical application, becoming the method of choice in many clinical genetics laboratories for the detection of disease-causing variants in a variety of genetic diseases involving multiple genes. The hemoglobinopathies are the most frequently found Mendelian inherited monogenic disease worldwide and are composed of a complex group of disorders frequently involving the inheritance of more than one abnormal gene. This review aims to present the role of NGS in both screening and pre- and post-natal diagnostics of the hemoglobinopathies, and the added value of NGS is discussed based on the results described in the literature. Overall, NGS has an added value in large-scale high throughput carrier screening and in the complex cases for which common molecular techniques have some inadequacies. It is proven that the majority of thalassemia cases and Hb variants can be diagnosed using routine analysis involving a combined approach of hematology, hemoglobin separation, and classical DNA methods; however, we conclude that NGS can be a useful addition to the existing methods in the diagnosis of these disorders.

Successful Implementation of Newborn Screening for Hemoglobin Disorders in the Philippines

The Philippine newborn bloodspot screening (NBS) program began in 1996 with 24 hospitals and was formalized by legislation in 2004. The NBS panel was recently expanded to include a number of additional hereditary congenital conditions. Expertise and experiences from other NBS programs already screening for hemoglobinopathies were essential to its successful integration into the ongoing dried bloodspot NBS program in the Philippines. Building on clinical experiences and population data from Filipinos born in California, USA, hemoglobinopathies (including thalassemias) were selected for inclusion in the expanded screening panel. Hemoglobinopathy NBS, using high performance liquid chromatography, was implemented in a stepwise manner into the seven regional NBS screening laboratories. A central university laboratory provides confirmatory testing using both capillary electrophoresis and molecular methodologies. NBS results indicating carriers are followed up with educational fact sheets, while results of presumptive disease are referred for confirmatory testing and follow-up with a hematologist. Long-term care is provided through newborn screening continuity clinics across the country. Hemoglobinopathy NBS is now included in the national insurance package and screening uptake continues to increase nationally, exceeding 90% of all newborns in 7400+ hospitals and birthing centers nationwide prior to the COVID-19 pandemic.

Genetic counseling in the context of Bangladesh: current scenario, challenges, and a framework for genetic service implementation

With the advancements in genetics and genomics in the twenty-first century, genetic services have become an integral part of medical practices in high-income and upper-middle-income countries. However, people living in low and lower-middle-income countries (LICs and LIMCs), including Bangladesh, are rather underprivileged in receiving genetic services. Consequently, genetic disorders are emerging as a significant public health concern in these countries. Lack of expertise, high expense, the dearth of epidemiological data, insufficiently updated medical education system, poor infrastructure, and the absence of comprehensive health policies are the main factors causing people living in these countries not having access to genetic services. In this article, the authors took benefit from their professional experience of practicing medical genetics in the area and reviewed existing literature to provide their opinions. Particularly, it reviews the current knowledge of genetic disorders' burden and their causative factors in Bangladesh. It focuses on why providing genetic services is challenging in the context of the country's cultural and religious sentiment. Finally, it proposes a physician-academician collaborative framework within the existing facility that aims to tackle the challenges. Such a framework could also be useful for other LICs and LMICs to address the challenges associated with providing genetic services.

Allele-Specific Recombinase Polymerase Amplification to Detect Sickle Cell Disease in Low-Resource Settings

Sickle cell disease (SCD) is a group of common, life-threatening disorders caused by a point mutation in the β globin gene. Early diagnosis through newborn and early childhood screening, parental education, and preventive treatments are known to reduce mortality. However, the cost and complexity of conventional diagnostic methods limit the feasibility of early diagnosis for SCD in resource-limited areas worldwide. Although several point-of-care tests are commercially available, most are antibody-based tests, which cannot be used in patients who have recently received a blood transfusion. Here, we describe the development of a rapid, low-cost nucleic acid test that uses real-time fluorescence to detect the point mutation encoding hemoglobin S (HbS) in one round of isothermal recombinase polymerase amplification (RPA). When tested with a set of clinical samples from SCD patients and healthy volunteers, our assay demonstrated 100% sensitivity for both the β^A globin and β^S globin alleles and 94.7 and 97.1% specificities for the β^A globin allele and β^S globin allele, respectively (n = 91). Finally, we demonstrate proof-of-concept sample-to-answer genotyping of genomic DNA from capillary blood using an alkaline lysis procedure and direct input of diluted lysate into RPA. The workflow is performed in <30 min at a cost of <$5 USD on a commercially available benchtop fluorimeter and an open-source miniature fluorimeter. This study demonstrates the potential utility of a rapid, sample-to-answer nucleic acid test for SCD that may be implemented near the point of care and could be adapted to other disease-causing point mutations in genomic DNA.

A Novel Frameshift Mutation, Deletion of HBB:c.199_202delAAAG [Codon 66/67 (-AAAG)] in β-Thalassemia Major Patients from the Western Region of Uttar Pradesh, India

Purpose

Beta thalassemia is one of the most common inherited disorders in India with heterogenous clinical phenotypes from silent carrier to clinically severe ones. Our study aimed to characterize the mutation spectrum in thalassemia patients who are coming to the hospital for follow-up from the western region of Uttar Pradesh India.

Patients and Methods

For the study, a case series of the retrospective bi-centre study was conducted. The patients from two thalassemia centers in the major hospitals (LLRMC Meerut, and JNMC, Aligarh administered by the Ministry of Health and Family Welfare (MoHFW)) in the Western Uttar Pradesh, India were considered for the study. A total of 77 blood samples were obtained from individuals (both related and unrelated) diagnosed with β-thalassemia after their consent. After DNA extraction, HBB gene amplification, mutation-specific polymerase chain reaction and gene sequencing were carried out to analyze the mutations.

Results

In this study, seven different types of mutations were reported for the first time in Western Uttar Pradesh, India. A novel frameshift mutation, deletion of 4 nucleotides Codon 66/67 (-AAAG) in exon 2 region, is reported for the first time. IVS 1-5 (G>C) and Codon 41/42 (-CTTT) are the most frequently reported mutations. The molecular spectrum for these two cases consists of 44 and 42 alleles out of 108 alleles, respectively.

Conclusion

A total of 108 β-thalassemia alleles were studied from 46 homozygous and 31 compound heterozygous patients. All the individuals were from 20 districts of the Western Uttar Pradesh, India.

Why is the novel Hb Miguel Servet visualised by CE-HPLC newborn and not by the CE-HPLC β-thalassaemia programme?

Screening of haemoglobinopathies is indicated for the detection of sickle cell anaemia; thus, neonates can benefit from early and adequate treatment that prevents neurological damage, reduces morbidity and mortality associated with the disease. These types of programmes sometimes lead to unexpected findings. We present a new haemoglobin (Hb) variant (Hb Miguel Servet) detected by newborn screening. During neonatal screening of haemoglobinopathies by cation-exchange high-performance liquid chromatography (CE-HPLC) newborn, an Hb variant was detected. An analysis at 8 months of age using capillary zone electrophoresis (CZE) confirmed the presence of this new Hb. The molecular characterisation was performed by automatic sequencing of the α and β globin genes in an ABI PRISM 3100 Genetic Analyzer. Hb analysis by CE-HPLC β-thalassaemia short programmedid not indicate the presence of abnormal Hbs. By CZE showed a peak in the zone 12 zone comprising 3.3% of the total Hb. A new analysis by CE-HPLC on a Tosoh G8-2 (Horiba) shown a peak, in the region of HbA1b, did not interfere with the quantification of HbA1c. Sequencing of the β gene revealed the substitution of a guanine for a thymine (GGT >TGT) in codon 69 of the second exon, resulting in substitution of cysteine for the amino acid glutamine (HBB:c.208G>T). Hb Miguel Servet is a β-chain globin variant detected by CE-HPLC newborn (BioRad), by CZE and by CE-HPLC-CE Tosoh G8-2 (Horiba), but no by CE-HPLC-CE β-thalassaemia short programme (BioRad). In fact, for all the techniques that are visualised, what would be detected would be the glutathione variant of Hb (Miguel Servet).

CYP450 Mediates Reactive Oxygen Species Production in a Mouse Model of β-Thalassemia through an Increase in 20-HETE Activity

Oxidative damage by reactive oxygen species (ROS) is one of the main contributors to cell injury and tissue damage in thalassemia patients. Recent studies suggest that ROS generation in non-transfusion-dependent (NTDT) patients occurs as a result of iron overload. Among the different sources of ROS, the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family of enzymes and cytochrome P450 (CYP450) have been proposed to be major contributors for oxidative stress in several diseases. However, the sources of ROS in patients with NTDT remain poorly understood. In this study, Hbbth3/+ mice, a mouse model for β-thalassemia, were used. These mice exhibit an unchanged or decreased expression of the major NOX isoforms, NOX1, NOX2 and NOX4, when compared to their C57BL/6 control littermates. However, a significant increase in the protein synthesis of CYP4A and CYP4F was observed in the Hbbth3/+ mice when compared to the C57BL/6 control mice. These changes were paralleled by an increased production of 20-hydroxyeicosatetraenoic acid (20-HETE), a CYP4A and CYP4F metabolite. Furthermore, these changes corroborate with onset of ROS production concomitant with liver injury. To our knowledge, this is the first report indicating that CYP450 4A and 4F-induced 20-HETE production mediates reactive oxygen species overgeneration in Hbbth3/+ mice through an NADPH-dependent pathway.

Bone marrow necrosis and fat embolism syndrome: a near fatal complication in previously undiagnosed sickle beta + thalassaemia

Prevalence of haemoglobin sickle-β⁺ thalassaemia (Hb S/β+thal) is variable with geography ranging from 0.2% to 10% among sickle cell patients. Clinical presentation of Hb S/β+thal patients depends on HbA level, with milder disease often going undiagnosed. However, rarely these patients can present with a fulminant vaso-occlusive crisis (VOC). Given VOC can present with non-specific symptoms, the diagnosis and treatment is often delayed. Here, we present a patient who initially developed altered mental status, pancytopenia and multiorgan failure due a critical VOC resulting in bone marrow necrosis and fat embolism. Subsequent workup confirmed that our patient had Sickle-β⁺ thalassaemia, which had gone undiagnosed, despite subclinical evidence of haemolysis on routine lab work for years. Following diagnosis and initiation of RBC exchange, he improved significantly and was discharged home. High index of suspicion and bone marrow biopsy is vital for early diagnosis and management of this rare condition.

Outcomes of haemoglobin Bart's hydrops fetalis following intrauterine transfusion in Ontario, Canada

OBJECTIVES

With improved access to intrauterine transfusion (IUT), more fetuses with haemoglobin Bart's hydrops fetalis (HBHF; homozygous α⁰-thalassaemia) will survive.

DESIGN

To evaluate the long-term outcome of affected fetuses with and without IUT in Ontario, Canada, we retrospectively collected data on IUTs and pregnancy outcomes in all cases of HBHF, from 1989 to 2014. Clinical outcome and neurocognitive profiles of long-term survivors were also collected and compared with data from 24 patients with transfusion-dependent β-thalassaemia (TDT-β).

RESULTS

Of the 99 affected pregnancies (93 prenatally diagnosed), 68 resulted in miscarriage or elective termination of pregnancy. Twelve mothers (12%) continued their pregnancies without IUT, and none of those newborns survived the first week of life. All 13 fetuses that received IUT(s) were live-born, but 3 died due to severe hydrops at birth and 1 died due to infection. The remaining nine survivors, in comparison with TDT-β patients, had earlier iron overload requiring iron chelation therapy. Endocrinopathies and short stature were more frequent in these patients. Neurocognitive outcome was not significantly affected in five patients who were assessed, and none were diagnosed with intellectual impairment. In three patients, MRI studies demonstrated brain white matter changes in keeping with 'silent' ischaemic infarcts.

CONCLUSIONS

In patients with HBHF, IUT is associated with improved survival. While acceptable neurocognitive outcome can be expected, these patients have more clinical complications compared with their TDT-β counterparts. The clinical and neurocognitive outcomes of HBHF should be discussed in detail when counselling and offering IUT for patients.

Adherence to Quality of Care Indicators and Location of Sickle Cell Care Within Indiana

Newborn screening (NBS) follow-up programs for infants with sickle cell disease (SCD) are highly variable among states. Initiated in 2009, Sickle SAFE, the NBS follow-up program for infants with SCD in Indiana, follows infants through home visits and phone contact. The current study assessed the attainment rates for recently published quality indicators of pediatric SCD care for Sickle SAFE participants. Using retrospective data, we determined the proportion of children who received transcranial Doppler (TCD) screening, influenza, and pneumococcal vaccination and were prescribed hydroxyurea. We calculated the mean age at confirmatory testing, time to receipt of penicillin prophylaxis, and mean age when genetic counseling was offered. One hundred ninety-eight children born with SCD in Indiana between July 1, 2009 and June 30, 2017 were followed for at least 1 year. While 97.5% received at least one dose of conjugated pneumococcal vaccine, vaccination with the 23 valent pneumococcal vaccine varied by location (county) of care (Allen: 14.3%, Lake: 26.7%, St. Joseph: 40.0%, Marion: 73.3%). Overall TCD screening rate for eligible children was 53%; TCD screening rate varied widely by location of care (Lake: 25% vs. Marion: 63.8%). Similarly, hydroxyurea prescribing practices varied significantly by location of care (p < 0.001). Identified gaps in adherence to quality indicators in SCD care will serve as the basis for future quality improvement initiatives.

Changing patterns in the epidemiology of β-thalassemia

β‐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, β‐thalassemia has been more common in certain regions of the world such as the Mediterranean, Middle East, and Southeast Asia. However, the prevalence of β‐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 β‐thalassemia as well as factors influencing disease frequency. The data suggest that the epidemiology of β‐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.

Sickle Cell-Related Complications in Patients Undergoing Cardiopulmonary Bypass

BACKGROUND

We aimed to describe our experience with patients with sickle cell trait (SCT) and undergoing surgery on cardiopulmonary bypass (CPB).

METHODS

Data on all patients with SCT or sickle-α thalassemia who underwent surgery on CPB were collected (1996-2017).

RESULTS

Overall, 46 patients were included, 37 (80%) had SCT and 9 (20%) had sickle-α thalassemia. A total of 4 (9%) developed a potential sickle cell-related complication. Patients with sickle cell-related complications were significantly older (median 14 years vs 14 months, P = .037) and heavier (median 54 kg vs 9 kg, P = .041). Complications occurred, although without statistical significance, in patients who underwent longer median CPB times (249 minutes vs 137 minutes, P = .069), lower median temperature (31.7 °C vs 33.3 °C, P = .094), and a higher percentage underwent deep hypothermic circulatory arrest (50% vs 7%, P = .053). A total of 30 (65%) patients underwent exchange transfusion (ET) pre-bypass. Patients who underwent ET were significantly older (median 4 years vs 7 months, P = .003) and heavier (median 16 kg vs 6 kg, P = .015) than patients who did not undergo ET. The incidence of complications was comparable between patients who underwent ET (10%) and those who did not (6%).

CONCLUSIONS

In this retrospective, single-center study, it has been shown that cardiac surgery requiring CPB in patients with SCT and sickle-α thalassemia had a low risk for sickle cell-associated complications. In this cohort of patients, older age, longer CPB times, lower median temperature, and the utilization of deep hypothermic circulatory arrest appear to play an important role in the development of complications.

[Prevalence of sickle cell trait in blood donors at the regional blood transfusion center in the Haute Matsiatra Region, Madagascar]

INTRODUCTION

sickle cell trait is the heterozygous form of sickle-cell disease. Patients with sickle cell trait can synthesize normal hemoglobin A and hemoglobin S. This condition has no recognizable clinical signs; then subjects with sickle cell trait, ignoring their genetic status, can be found among blood donors. This can have severe impact on donors´ health status and on that of recipients, especially if these have sickle-cell trait. The purpose of our study is to determine the prevalence of sickle cell trait in blood donors.

METHODS

we conducted a 4-month descriptive prospective study (January-May 2017) at the Haute Matsiatra Regional Blood Transfusion Center (RBTC). All donors were screened by Emmel test and positive cases were confirmed by hemoglobin electrophoresis.

RESULTS

the study involved 427 donors, of whom 332 were men and 95 women (sex ratio 3.4). The average age of blood donors was 32.72, ranging from 18 to 64 years. Emmel test was positive in 5 donors (1.17%). These patients had the AS genotype confirmed by hemoglobin electrophoresis.

CONCLUSION

the results of this study reveal the presence of sickle cell trait among blood donors at the CRTS. Most of them ignore their sickle cell status before blood donation. Quality and safety of blood and blood products are mandatory, hence the importance of screening among blood donors is a current relevant issue.

A Report on the Education, Employment and Marital Status of Thalassemia Patients from a Tertiary Care Center in the Middle East

Very few reports in the literature have focused on the psychosocial status of patients with thalassemia. The aim of this study was to report on the education, employment, and marital status of thalassemia patients in Lebanon and potential influencing factors. A total of 228 patients from the Chronic Care Center, Hazmieh, Lebanon, were incorporated for the data analysis. Demographic, social, and clinical variables were collected. Statistical analysis was performed using the Pearson χ² test, Fisher Exact test, and binary logistic regression. In this sample, 54.4% were employed, and 45.6% not employed. Of those employed, 65.3% were male, 62.9% single or divorced, 77.4% splenectomized. University level was reached by 26.3% subjects, 7.9% reached high school level, and 32.5% have a level less than high school. Multivariate analysis revealed higher education was most likely attained by males [odds ratio (OR) = 2.23, 95% confidence interval (95% CI): 0.23-0.86] and those with no heart disease and no joint disease (OR = 27.5, 95% CI: 2.80-270 and OR = 3.40, 95% CI: 0.90-12.7, respectively). For employment, a lower average ferritin was associated with current employment. Neither the type of thalassemia nor transfusion status or type of chelation therapy corresponded with higher education or employment status. In conclusion, this is one of the few studies in the literature to look at education, employment, and marital status of thalassemia patients. Such information is essential to develop effective psychosocial support plans for our thalassemia patients.

Umbilical Cord Blood Screening for the Detection of Common Deletional Mutations of α-Thalassemia in Bangladesh

α-Thalassemia (α-thal) is assumed to be very prevalent in Bangladesh. We aimed to assess the prevalence of the disease in the country and provide a model for α-thal newborn screening in Bangladesh. We collected umbilical cord blood (UCB) samples from 413 unrelated newborns in Bangladesh. Demographic information, blood indices, osmotic fragility, serum iron (Fe), and zinc (Zn) levels were evaluated for all the subjects. All subjects underwent a polymerase chain reaction (PCR)-based diagnosis for α-thal status, followed by a multiplex gap-PCR-based identification of the deletion type present. Sixty-seven subjects had at least one α-thal deletion (16.22%). We observed that -α^3.7 (rightward), - -^SEA (Southeast Asian), -α^4.2 (leftward), - -^MED (Mediterranean) and - -^THAI (Thailand) deletions were the most common α-globin deletions present in the country, with the -α^3.7 (n = 37) and - -^SEA (n = 18) being most prevalent. The osmotic fragility test (OFT) could predict the presence of α-thal deletions with over 98.0% sensitivity. Complete UCB count analysis revealed significant differences between healthy subjects and subjects with α-thal deletions. Although the iron level was almost the same (108.0 vs. 105.7 µg/dL), a reduced level of Zn (98.6 vs. 71.8 µg/dL, p < 0.01) was observed in the cord blood-derived serum of the subjects with α-thal deletions. Moreover, parental age at the time of delivery, gestational period, and birth weight was lower in the subjects with α-thal deletions. This study provides partial information on the epidemiology of α-thal in Bangladesh and describes a model for α-thal newborn screening in the country.

Impact of Medicaid expansion on access and healthcare among individuals with sickle cell disease

PURPOSE

Sickle cell disease (SCD) is associated with high acute healthcare utilization. The purpose of this study was to examine whether Medicaid expansion in California increased Medicaid enrollment, increased hydroxyurea prescriptions filled, and decreased acute healthcare utilization in SCD.

METHODS

Individuals with SCD (≤65 years and enrolled in Medicaid for ≥6 total calendar months any year between 2011 and 2016) were identified in a multisource database maintained by the California Sickle Cell Data Collection Program. We describe trends and changes in Medicaid enrollment, hydroxyurea prescriptions filled, and emergency department (ED) visits and hospital admissions before (2011-2013) and after (2014-2016) Medicaid expansion in California.

RESULTS

The cohort included 3635 individuals. Enrollment was highest in 2014 and lowest in 2016 with a 2.8% annual decease postexpansion. Although <20% of the cohort had a hydroxyurea prescription filled, the percentage increased by 5.2% annually after 2014. The ED visit rate was highest in 2014 and decreased slightly in 2016, decreasing by 1.1% annually postexpansion. Hospital admission rates were similar during the pre- and postexpansion periods. Young adults and adults had higher ED and hospital admission rates than children and adolescents.

CONCLUSIONS

Medicaid expansion does not appear to have improved enrollment or acute healthcare utilization among individuals with SCD in California. Future studies should explore whether individuals with SCD transitioned to other insurance plans or became uninsured postexpansion, the underlying reasons for low hydroxyurea utilization, and the lack of effect on hospital admissions despite a modest effect on ED visits.

Improving an Administrative Case Definition for Longitudinal Surveillance of Sickle Cell Disease

Objective:

Several states are building infrastructure and data collection methods for longitudinal, population-based surveillance systems for selected hemoglobinopathies. The objective of our study was to improve an administrative case definition for sickle cell disease (SCD) to aid in longitudinal surveillance.

Methods:

We collected data from 3 administrative data sets (2004-2008) on 1998 patients aged 0-21 in Georgia who had ≥1 encounter in which an SCD International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) code was recorded, and we compared these data with data from a laboratory and medical record review. We assessed performance (sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) of case definitions that differed by number and type of SCD-coded encounters; addition of SCD-associated treatments, procedures, and complications; and length of surveillance (1 vs 5 years). We identified correct diagnoses for patients who were incorrectly coded as having SCD.

Results:

The SCD case definition of ≥3 SCD-coded encounters in 5 years simplified and substantially improved the sensitivity (96.0% vs 85.8%) and NPV (68.2% vs 38.2%) of the original administrative case definition developed for 5-year, state-based surveillance (≥2 encounters in 5 years and ≥1 encounter for an SCD-related treatment, procedure, or complication), while maintaining a similar PPV (97.4% vs 97.4%) and specificity (76.5% vs 79.0%).

Conclusions:

This study supports an administrative case definition that specifies ≥3 ICD-9-CM–coded encounters to identify SCD with a high degree of accuracy in pediatric patients. This case definition can be used to help establish longitudinal SCD surveillance systems.

Alpha-Thalassemia in North Morocco: Prevalence and Molecular Spectrum

Unlike the other hemoglobinopathies, few researches have been published concerning α-thalassemia in Morocco. The epidemiological features and the mutation spectrum of this disease are still unknown. This regional newborn screening is the first to study α-thalassemia in the north of Morocco. During the period from January 2015 to December 2016, 1658 newborns umbilical blood samples were investigated. Suspected newborns were screened for α-globin defects using Gap-PCR and Multiplex Ligation-dependent Probe Amplification technique. The prevalence of α-thalassemia, its mutation spectrum, and its allelic frequencies were described for the first time in Morocco. Six different α-globin genetic disorders were detected in 16 neonates. This screening valued the prevalence of α-thalassemia in the studied population at 0.96% and showed the wide mutation spectrum and the heterogeneous geographical distribution of the disease. A high rate of carriers was observed in Laouamra, a rural commune in Larache province. Heterogeneity of α-globin alleles in Morocco explains the high variability of α-thalassemia severity. This diversity reflects the anthropological history of the country. These results would contribute to the prevention of thalassemia in Morocco directing the design of a nationwide screening strategy and awareness campaign.

Leveraging Evidence-Based Public Policy and Advocacy to Advance Newborn Screening in California

In 2016, the EveryLife Foundation for Rare Diseases, in partnership with Dr Pan, who is a pediatrician and state senator in California, launched legislation to advance and expand newborn screening. Researchers have shown that newborn screening can be cost-effective and can greatly improve health outcomes for patients with rare diseases. However, adding additional diseases in newborn screening is a long process, requiring legislative approval in addition to new state funding. Such process delays can lead to protracted diagnostic odysseys for patients, especially those with rare diseases. These delays can result in irreversible morbidity and, in some cases, early mortality for patients. To improve this process, legislation known as Senate Bill 1095 was introduced to require California to adhere to the latest federal recommendations for newborn screening within 2 years. We provide insight and describe the process of advancing state legislation, coalition building, and managing opposition. Senate Bill 1095 would become law in 2016, requiring California to screen for 2 new rare diseases by August 2018: mucopolysaccharidosis type I and Pompe disease. This case study can serve as a model for advocates looking to expand state newborn-screening programs.

Vascular and hemostatic alterations associated with pulmonary hypertension in β-thalassemia hemoglobin E patients receiving regular transfusion and iron chelation

INTRODUCTION

Pulmonary hypertension (PH) is the commonest cardiac complication in β-thalassemia intermedia, including β-thalassemia/hemoglobin E (β-thal/HbE), and is strongly associated with splenectomy. We aimed to define the prevalence and comprehensively explore mechanisms of PH in β-thal/HbE patients receiving regular transfusion and iron chelation, which were reported to alleviate PH.

MATERIALS AND METHODS

β-Thal/HbE patients receiving regular transfusion and iron chelation over one year were enrolled. Patients at risk for PH were defined by tricuspid-regurgitant-jet-velocity (TRV) ≥ 2.5 m/s. Laboratory and echocardiographic variables were compared with healthy controls.

RESULTS

There were 68 β-thal/HbE, including 31 (45.6%) splenectomized patients, and 38 controls included for analysis. PH was detected in 29 β-thal/HbE (42.6%). β-Thal/HbE with PH had a significant reduction in nitric oxide metabolites (NOx) but elevations in thrombin-antithrombin (TAT) complex, soluble thrombomodulin (sTM), endothelin-1 (ET-1) and flow-mediated dilation (FMD) values compared to those without PH (all, p < 0.05). TRV was significantly correlated with NOx, TAT, sTM, ET-1 and FMD values (r = -0.514, r = 0.281, r = 0.313, r = 0.245 and r = -0.474; all p < 0.05). Erythropoietic activity, serum ferritin, circulating total tissue factor (TF) antigen, microparticle-associated TF activity, microparticle's procoagulant activity and soluble p-selectin levels were not different between PH and non-PH subgroups. Notably, there were no significant associations between splenectomy and PH.

CONCLUSIONS

PH remains prevalent in β-thal/HbE patients receiving long-term transfusion and iron chelation. PH is not associated with splenectomy status but correlated with NO depletion, TF-independent hypercoagulability and endothelial perturbation.

Newborn Screening for Sickle Cell Disease: Indian Experience

Sickle cell disease (SCD) is a major public health problem in India with the highest prevalence amongst the tribal and some non-tribal ethnic groups. The clinical manifestations are extremely variable ranging from a severe to mild or asymptomatic condition. Early diagnosis and providing care is critical in SCD because of the possibility of lethal complications in early infancy in pre-symptomatic children. Since 2010, neonatal screening programs for SCD have been initiated in a few states of India. A total of 18,003 babies have been screened by automated HPLC using either cord blood samples or heel prick dried blood spots and 2944 and 300 babies were diagnosed as sickle cell carriers and SCD respectively. A follow up of the SCD babies showed considerable variation in the clinical presentation in different population groups, the disease being more severe among non-tribal babies. Around 30% of babies developed serious complications within the first 2 to 2.6 years of life. These pilot studies have demonstrated the feasibility of undertaking newborn screening programs for SCD even in rural areas. A longer follow up of these babies is required and it is important to establish a national newborn screening program for SCD in all of the states where the frequency of the sickle cell gene is very high followed by the development of comprehensive care centers along with counselling and treatment facilities. This comprehensive data will ultimately help us to understand the natural history of SCD in India and also help the Government to formulate strategies for the management and prevention of sickle cell disease in India.

Variability in State-Based Recommendations for Management of Alpha Thalassemia Trait and Silent Carrier Detected on the Newborn Screen

We conducted an inventory of state-based recommendations for follow-up of alpha thalassemia silent carrier and trait identified on newborn screen. We found wide variability in the nature and timing of these recommendations. We recommend a standardized recommendation to guide pediatricians in evidenced-based care for this population.

A Mild Phenotype of Severe β+ Thalassemia in a 16-Month-Old Boy

β thalassemia is characterized by a deficient production of functional β-globin chains and a relative excess of α-globin chains. An extremely diverse clinical spectrum-asymptomatic to transfusion-dependent-is primarily due to homozygosity or compound heterozygosity for the very large number of β-thalassemia-causing mutations, along with interacting mutations that affect the α-globin and γ-globin genes and their expression. We report a case of a 16-month-old boy who was initially diagnosed with iron deficiency anemia until he was later found to be homozygous for a severe β-thalassemia genotype with a mild hematologic phenotype. This was likely as a result of his ability to produce high levels of fetal hemoglobin.

Antibiotic Prophylaxis for Children With Sickle Cell Anemia

BACKGROUND

Children with sickle cell anemia (SCA) are at increased risk for invasive pneumococcal disease; antibiotic prophylaxis significantly reduces this risk. We calculated the proportion of children with SCA who received ≥300 days of antibiotic prophylaxis and identified predictors of such receipt.

METHODS

Children aged 3 months to 5 years with SCA were identified by the presence of 3 or more Medicaid claims with a diagnosis of SCA within a calendar year (2005-2012) in Florida, Illinois, Louisiana, Michigan, South Carolina, and Texas. Receipt of antibiotics was identified through claims for filled prescriptions. The outcome, receipt of ≥300 days of antibiotics, was assessed annually by using varying classifications of antibiotics. By using logistic regression with generalized estimating equations, we estimated the odds of receiving ≥300 days of antibiotics, with potential predictors of age, sex, year, state, and health services use.

RESULTS

A total of 2821 children contributed 5014 person-years. Overall, only 18% of children received ≥300 days of antibiotics. Each additional sickle cell disease-related outpatient visit (odds ratio = 1.01, 95% confidence interval: 1.01-1.02) and well-child visit (odds ratio = 1.08, 95% confidence interval: 1.02-1.13) was associated with incrementally increased odds of receiving ≥300 days of antibiotics.

CONCLUSIONS

Despite national recommendations and proven lifesaving benefit, antibiotic prophylaxis rates are low among children with SCA. Numerous health care encounters may offer an opportunity for intervention; in addition, such interventions likely need to include social factors that may affect the ability for a child to receive and adhere to antibiotic prophylaxis.

Sickle Cell Beta-Plus Thalassemia with Subcapsular Hematoma of the Spleen

While splenic complications like hypersplenism, sequestration crisis, and infarction are commonly reported in sickle cell variants like sickle cell beta-plus thalassemia, splenic rupture with hematoma is rare. We present a case of a 32-year-old young male who presented with dull left upper quadrant pain who was found to have multiple subcapsular splenic lacerations and hematoma on abdominal imaging. Hemoglobin electrophoresis confirmed sickle cell beta-plus thalassemia in the patient. There was no history of trauma, and rest of the workup for possible cause of spontaneous rupture of spleen was negative. With the patient refusing splenectomy, he was managed conservatively. Clinicians need to be aware of this rare complication of sickle cell variants.

Thalassaemia

Inherited haemoglobin disorders, including thalassaemia and sickle-cell disease, are the most common monogenic diseases worldwide. Several clinical forms of α-thalassaemia and β-thalassaemia, including the co-inheritance of β-thalassaemia with haemoglobin E resulting in haemoglobin E/β-thalassaemia, have been described. The disease hallmarks include imbalance in the α/β-globin chain ratio, ineffective erythropoiesis, chronic haemolytic anaemia, compensatory haemopoietic expansion, hypercoagulability, and increased intestinal iron absorption. The complications of iron overload, arising from transfusions that represent the basis of disease management in most patients with severe thalassaemia, might further complicate the clinical phenotype. These pathophysiological mechanisms lead to an array of clinical manifestations involving numerous organ systems. Conventional management primarily relies on transfusion and iron-chelation therapy, as well as splenectomy in specific cases. An increased understanding of the molecular and pathogenic factors that govern the disease process have suggested routes for the development of new therapeutic approaches that address the underlying chain imbalance, ineffective erythropoiesis, and iron dysregulation, with several agents being evaluated in preclinical models and clinical trials.

Non-Transfusion-Dependent Thalassemia: An Update on Complications and Management

Patients with non-transfusion-dependent thalassemia (NTDT) experience many clinical complications despite their independence from frequent transfusions. Morbidities in NTDT stem from the interaction of multiple pathophysiological factors: ineffective erythropoiesis, iron overload (IOL), and hypercoagulability. Ineffective erythropoiesis and hemolysis are associated with chronic hypoxia and a hypercoagulable state. The latter are linked to a high prevalence of thromboembolic and cerebrovascular events, as well as leg ulcers and pulmonary hypertension. IOL in NTDT patients is a cumulative process that can lead to several iron-related morbidities in the liver (liver fibrosis), kidneys, endocrine glands (endocrinopathies), and vascular system (vascular disease). This review sheds light on the pathophysiology underlying morbidities associated with NTDT and summarizes the mainstays of treatment and some of the possible future therapeutic interventions.

Cut-Off Values of Hematologic Parameters to Predict the Number of Alpha Genes Deleted in Subjects with Deletional Alpha Thalassemia

Most α-thalassemia cases are caused by deletions of the structural α-globin genes. The degree of microcytosis and hypochromia has been correlated with the number of affected α-globin genes, suggesting a promising role of hematologic parameters as predictive diagnostic tools. However, cut-off points for these parameters to discriminate between the different subtypes of α-thalassemia are yet to be clearly defined. Six hematologic parameters (RBC, Hb, MCV, MCH, MCHC and RDW) were evaluated in 129 cases of deletional α-thalassemia (56 heterozygous α⁺ thalassemia, 36 homozygous α⁺ thalassemia, 29 heterozygous α⁰ thalassemia and 8 cases of Hb H disease). A good correlation between the number of deleted alpha genes and MCV (r = −0.672, p < 0.001), MCH (r = −0.788, p < 0.001) and RDW (r = 0.633, p < 0.001) was observed. The presence of an α⁰ allele should be discarded in individuals with microcytosis without iron deficiency and normal values of Hb A₂ and Hb F with MCH < 23.40 pg. Furthermore, MCH < 21.90 pg and/or MCV < 70.80 fL are strongly suggestive of the presence of one α⁰ allele. Finally, an accurate presumptive diagnosis of Hb H disease can be made if both RDW ≥ 20% and MCH < 19 pg are seen.

The Prevalence and Role of Hemoglobin Variants in Biometric Screening of a Multiethnic Population: One Large Health System's Experience

OBJECTIVES

To characterize and quantitate hemoglobin (Hb) variants discovered during biometric hemoglobin A1c (HbA1c) analyses in a large multiethnic population with a focus on the effect of variants on testing method and results.

METHODS

In total, 13,913 individuals had their HbA1c measured via ion-exchange high-performance liquid chromatography. Samples that had a variant Hb detected or HbF fraction more than 25% underwent variant Hb characterization and confirmation by gel electrophoresis. RBC indices were also evaluated for possible concomitant thalassemia.

RESULTS

Of the 13,913 individuals evaluated, 524 (3.77%) had an Hb variant. The prevalence of each variant was as follows: HbS trait (n = 396, 2.85%), HbSS disease (n = 4, 0.03%), HbC trait (n = 85, 0.61%), HbCC disease (n = 2, 0.01%), HbSC disease (n = 5, 0.04%), HbE trait (n = 18, 0.13%), HbD or G trait (n = 9, 0.06%), HbS β-thalassemia + disease (n = 1, 0.01%), hereditary persistence of HbF (n = 2, 0.01%), and HbMontgomery trait (n = 1, 0.01%). Concomitant α-thalassemia was detected in 20 (3.82%) of the 524 individuals with an Hb variant.

CONCLUSIONS

This study represents one of the largest epidemiologic investigations into the prevalence of Hb variants in a North American metropolitan, multiethnic workforce and their dependents and reinforces the importance of method selection in populations with Hb variants.

Non-Transfusion-Dependent Thalassaemia: A Panoramic Survey from Pathophysiology to Treatment

Non-transfusion-dependent thalassaemia (NTDT) is a rather broad term that encompasses a group of thalassaemia syndromes, most commonly β-thalassaemia intermedia, haemoglobin E/β-thalassemia, and α-thalassaemia intermedia (haemoglobin H disease). Importantly, these entities do not require regular blood transfusions for survival, and therefore have transfusion independence. Clinical morbidities associated with the NTDTs are the end result of the culmination of three principal pathophysiological aberrancies: ineffective erythropoiesis, chronic anaemia (and associated haemolysis), and iron overload. Such complications involve multiple organs and organ systems; hence, the importance of prompt identification of at-risk individuals and holistic management of diagnosed subjects can never be overstated. Several management options, both medical and surgical, remain at the disposal of involved clinicians, with a significant body of data favouring the virtue of iron chelation therapy, fetal haemoglobin induction, and treatment with blood transfusions, the latter only when absolutely indicated, with reservation of splenectomy to a few select cases. Yet, a better understanding of the molecular phenomena at the origin of the disease process in the NTDT syndromes calls for a pressing need to explore novel therapeutic modalities, in light of the increasing incidence of NTDT in the developed world.

Favorable outcomes after in utero transfusion in fetuses with alpha thalassemia major: a case series and review of the literature

OBJECTIVE

Alpha thalassemia major (ATM) is often fatal in utero due to severe hydrops fetalis. Although in utero transfusions (IUTs) are increasingly used to allow fetal survival in ATM, prenatal and postnatal outcomes are not well described.

METHODS

We retrospectively reviewed cases of ATM at our institution treated with consecutive IUT. Clinical records were reviewed for transfusion history, neurodevelopmental outcomes, anatomic abnormalities, survival to hematopoietic cell transplantation, and transfusion independence. A systematic review was performed, and additional reported cases are discussed.

RESULTS

Three patients who underwent IUT for ATM were identified, and review of the literature revealed 17 reported cases. Of patients who received IUT, reported neurodevelopmental deficits occurred in 29% (4/14) and anatomic abnormalities in 55% (11/20). Four patients eventually underwent successful hematopoietic cell transplantation. Transfusion volumes were less than suggested guidelines for other causes of fetal anemia in 91.7% of the transfusions.

CONCLUSION

This series demonstrates the potential for achieving full fetal development with normal neurologic outcomes in those affected by ATM. It provides support for continued patient and provider education about current benefits and risks of active prenatal therapy for fetuses with ATM, as well as continued research to optimize therapeutic strategies such as in utero transplantation. © 2016 John Wiley & Sons, Ltd.