The spectrum of beta-thalassemia mutations in the 22 Arab countries: a systematic review

Luspatercept's use in a patient with transfusion-dependent beta-thalassemia and intrathoracic extramedullary hematopoiesis (EMH)

Key Clinical Message

This case report and literature review examine the use of a relatively novel agent in a transfusion-dependent beta-thalassemia patient with extramedullary hematopoiesis (EMH). It examines the benefits and risks associated with its use and reviews the available literature while highlighting the drug's results in our patient with a higher risk profile.

Abstract

Beta thalassemia can be complicated by EMH, which causes different symptoms based on location and size. Luspatercept is a new agent approved for transfusion-dependent thalassemia and Non-transfusion-dependent thalassemia (NTDT). Still, its use in patients with EMH was not well studied, and literature showed an increased risk of EMH expansion or development of new masses after its use. We discuss, in this case, the results of luspatercept treatment in a patient with transfusion-dependent thalassemia who is considered high risk for its use due to the patient's specific characteristics (history of symptomatic intrathoracic EMH, previous splenectomy, refusal to use antithrombotic medications). While also highlighting the benefits of using luspatercept regarding decreasing the iron overload and improving hemoglobin levels and examining how it was used safely to manage a transfusion-dependent thalassemia patient with an extramedullary hematopoiesis mass with no adverse events of note.

Management of transfusion-dependent β-thalassemia (TDT): Expert insights and practical overview from the Middle East

β-Thalassemia is one of the most common monogenetic diseases worldwide, with a particularly high prevalence in the Middle East region. As such, we have developed long-standing experience with disease management and devising solutions to address challenges attributed to resource limitations. The region has also participated in the majority of clinical trials and development programs of iron chelators and more novel ineffective erythropoiesis-targeted therapy. In this review, we provide a practical overview of management for patients with transfusion-dependent β-thalassemia, primarily driven by such experiences, with the aim of transferring knowledge to colleagues in other regions facing similar challenges.

Combatting thalassemia in the United Arab Emirates

Thalassemia is a major health challenge in the United Arab Emirates (UAE), however previous studies have focused on genetics and molecular characterisation while neglecting culture and society. In this commentary, we discuss how tradition and religion in the UAE (e.g. consanguinity, endogamy, illegality of abortion and in vitro fertilisation, adoption restrictions), and limited academic research, affect the prevention and management of the blood disorder. It is suggested that changing attitudes towards traditional marriage practices, education and awareness campaigns targeting families and young people, and earlier genetic testing, are culturally acceptable solutions to curbing the high incidence of thalassemia in the UAE.

Perception of consanguineous marriage among the qatari population

Background

Hereditary blood diseases are widespread among the Arab population due to the high rates of consanguineous marriages; research regarding the perception of consanguineous marriage in some countries, such as Qatar, is extremely scarce. Therefore, this study aimed to investigate the prevalence of consanguineous marriage and assess the perception of consanguineous marriage among the Qatari population.

Methods

A cross-sectional study used a self-administered questionnaire among 395 Qatari adults aged 18-35 who attended primary healthcare institutions in Qatar. A convenience sampling technique was used to select the study participants. An independent t-test was used to compare the significance of the mean between the two groups with positive and negative perceptions of consanguineous marriage. Categorical data were analyzed for association using the chi-square or Fisher's exact test. Finally, a multiple logistic regression analysis was conducted to determine the significant predictors of the positive perception of consanguineous marriage. A significant level was set at p < 0.05.

Results

Approximately 45% of the participants had a positive perception toward consanguineous marriage, and the most common reason stated by those participants was "habit and traditions." The prevalence of consanguineous marriage among married couples was 62.6%, and among those with consanguineous marriage, most were married to first cousins (81.7%). Moreover, compared to the participants with negative perceptions of consanguineous marriage, those with positive ones were significantly older, married, with lower educational levels and higher monthly income levels, did not hear about glucose-6-phosphate dehydrogenase (G6PD) deficiency, did not know what kinds of diseases are being screened in the premarital test, and were married to a relative.

Conclusion

The prevalence of consanguineous marriage is high among the Qatari population, and this requires an immediate need for community-based campaigns to raise public awareness about the problem and its potential impact.

Applications of Artificial Intelligence in Thalassemia: A Comprehensive Review

Thalassemia is an autosomal recessive genetic disorder that affects the beta or alpha subunits of the hemoglobin structure. Thalassemia is classified as a hypochromic microcytic anemia and a definitive diagnosis of thalassemia is made by genetic testing of the alpha and beta genes. Thalassemia carries similar features to the other diseases that lead to microcytic hypochromic anemia, particularly iron deficiency anemia (IDA). Therefore, distinguishing between thalassemia and other causes of microcytic anemia is important to help in the treatment of the patients. Different indices and algorithms are used based on the complete blood count (CBC) parameters to diagnose thalassemia. In this article, we review how effective artificial intelligence is in aiding in the diagnosis and classification of thalassemia.

Extramedullary haematopoiesis in patients with transfusion dependent β-thalassaemia (TDT): a systematic review

INTRODUCTION

Around 5% of the world's population is expected to have some degree and type of thalassaemia. Beta thalassaemia (BT) occurs due to a deficient production of the beta-globin chain of haemoglobin. Extramedullary haematopoiesis (EMH) is one of the complications of BT, mainly observed in minor/intermedia subtypes. EMH is the production of blood cells outside the marrow as a compensatory response to longstanding hypoxia. Due to chronic transfusions, it is not expected in patients with beta-thalassaemia major (BTM). However, there are increasingly reported cases of EMH in BTM. The incidence of EMH in BTM is thought to be <1%. We aim to pool the available data and provide cumulative evidence on the occurrence of EMH in BTM patients.

METHODS

This is a systematic review of case reports, series, and retrospective studies that presented data on the occurrence of EMH in BTM patients. Data were recorded and analyzed in Microsoft Excel 2016 and SPSS 26. The protocol has been registered in PROSPERO: CRD42021242943.

RESULTS

Data from 253 cases of EMH in BTM patients were extracted with a mean age of 35.3 years. Mean haemoglobin at presentation with EMH was 8.2 mg/dL. Lower limb weakness was the most common presenting feature (N = 23) (paraspinal EMH). Magnetic resonance imaging (MRI) was the most widely used diagnostic modality (226). Overall, blood transfusion was the commonest reported treatment (30), followed by radiotherapy (20), surgery (15), hydroxyurea (12), steroids (6), and exchange transfusion (2). An outcome was reported in 20% of patients, all recovered, except one who died as a result of nosocomial infection.

CONCLUSION

EMH is rare in BTM and can occur in any organ system with varied clinical features. MRI can effectively diagnose EMH, and conservative management has similar results compared to invasive treatments. Larger studies, focussing on outcomes may enhance guidelines on preventive and therapeutic strategies for managing EMH in BTM.KEY MESSAGESExtramedullary haematopoiesis is a rare complication in beta thalassaemia. Although it is more common in non-transfusion dependent thalassaemia, increasingly reported cases suggest a higher prevalence of EMH in TDT than what is known before.There are no clear guidelines on the management of EMH in TDT, with reported patients showing similar outcomes with conservative invasive treatment modalities.More extensive and preferably prospectively designed studies are required focussing on the management of EMH and its outcomes in patients with TDT to formulate evidence-based guidelines.

Red Blood Cell Alloimmunization in Pediatric group with Beta Thalassemia: A Five-Year Experience

Beta-thalassemia is one of the most frequently occurring hematological disorders in [Removed for blinded peer-review]. Regular blood transfusion is required in almost all cases for management. However, this is associated with significant major complications like red blood cell (RBC) alloimmunization. This retrospective cross-sectional is conducted to evaluate the RBC alloimmunization frequency in children with beta-thalassemia aged between 6 months and 16 years in [Removed for blinded peer-review]. Antibody screening was performed using the Dia clon3 cell antigen panel. If the screening came back positive, a detailed panel was created for the identification of specific antibody. In our sample, the frequency of RBC alloimmunization was found in 22 (26.19%) patients. Of these 22 patients, the Rhesus system was found in most patients 17 (77.3%), followed by Kell 5 (22.7%). RBC alloimmunization was significantly associated with a family history of a blood disorder and splenectomy.

The spectrum of chromosomal translocations in the Arab world: ethnic-specific chromosomal translocations and their relevance to diseases

Chromosomal translocations (CTs) are the most common type of structural chromosomal abnormalities in humans. CTs have been reported in several studies in the Arab world, but the frequency and spectrum of these translocations are not well characterized. The aim of this study is to conduct a systematic review to estimate the frequency and spectrum of CTs in the 22 Arab countries. Four literature databases were searched: PubMed, Science Direct, Scopus, and Web of Science, from the time of inception until July 2021. A combination of broad search terms was used to collect all possible CTs reported in the Arab world. In addition to the literature databases, all captured CTs were searched in three chromosomal rearrangement databases (Mitelman Database, CytoD 1.0 Database, and the Atlas of Genetics and Cytogenetics in Oncology and Hematology), along with PubMed and Google Scholar, to check whether the CTs are unique to the Arabs or shared between Arabs and non-Arabs. A total of 9,053 titles and abstracts were screened, of which 168 studies met our inclusion criteria, and 378 CTs were identified in 15 Arab countries, of which 57 CTs were unique to Arab patients. Approximately 89% of the identified CTs involved autosomal chromosomes. Three CTs, t(9;22), t(13;14), and t(14;18), showed the highest frequency, which were associated with hematological malignancies, recurrent pregnancy loss, and follicular lymphoma, respectively. Complex CTs were commonly reported among Arabs, with a total of 44 CTs, of which 12 were unique to Arabs. This is the first study to focus on the spectrum of CTs in the Arab world and compressively map the ethnic-specific CTs relevant to cancer. It seems that there is a distinctive genotype of Arabs with CTs, of which some manifested with unique clinical phenotypes. Although ethnic-specific CTs are highly relevant to disease mechanism, they are understudied and need to be thoroughly addressed.

Recurrent spinal cord compression due to extramedullary hematopoiesis in thalassemia patient: Case report

INTRODUCTION

Spinal cord compression secondary to extramedullary hematopoiesis (EMH) is a rare condition. Variable treatment options have been reported with different efficacy and recurrence rate. Due to its rarity, no clear optimal management guidelines have been established yet.

PATIENT CONCERNS AND DIAGNOSIS

We report a recurrence of spinal cord compression secondary to EMH in a 19-year-old male, with a background of transfusion-dependent beta-thalassemia on luspatercept, who presented with weakness in both lower limbs.

INTERVENTIONS AND OUTCOMES

He was treated successfully both times with radiotherapy.

CONCLUSION

Early diagnosis and management of EMH compressing the spinal cord are essential to prevent permanent neurological damage. Diagnosis should be suspected based on the clinical presentation and magnetic resonance imaging findings in a patient with a history of ineffective hemopoiesis. Treatment option remains controversial. Radiotherapy option seems effective, even in recurrent cases, and valid, particularly for those at high risk of surgery or who do not prefer it.

Clinical image report of acute Cholangitis in Beta‐thalassemia major

Beta‐thalassemia is congenital red blood cell disorder. Gallstones is a recognized complication due to recurrent hemolysis. Acute cholangitis is a rare complication might occur in patient with beta‐thalassemia. We report a case of acute cholangitis in patient with beta‐thalassemia with Gilbert syndrome. We present a case of a young female of Arabic descent with acute abdomen. Workup revealed acute cholangitis with gallstones in the common bile duct. The ERCP was used to extract the stones than cholecystectomy.

The Superiority of T2*MRI Over Serum Ferritin in the Evaluation of Secondary Iron Overload in a Chronic Kidney Disease Patient: A Case Report

Secondary iron overload is increasingly encountered in chronic kidney disease (CKD) patients because of the frequent use of parenteral iron products, especially in hemodialysis patients. Serum ferritin has been commonly used to monitor iron overload in these patients; however, other conditions can be associated with the high serum ferritin, like infections and inflammatory conditions. Currently, T2*MRI of the heart and liver is the preferred investigation for evaluating liver iron concentration (LIC) and cardiac iron concentration, which reflect the state of iron overload. Few studies observe a positive correlation between serum iron and LIC in CKD patients and postulate that serum ferritin exceeding 290 mcg/L should indicate significant iron overload and necessitates further MRI evaluation. However, here, we present a patient with a history of ESRD for which she underwent renal transplantation twice referred to our clinic due to persistent elevation in serum ferritin level (>1000 mcg/L) for several years. T2*MRI of the heart and liver revealed the absence of iron overload. Our objective of this case is to demonstrate the accuracy of T2*MRI over serum ferritin in evaluating iron overload and questioning the positive correlation between serum ferritin and LIC in CKD patients.

Molecular classification of blood and bleeding disorder genes

The advances and development of sequencing techniques and data analysis resulted in a pool of informative genetic data, that can be analyzed for informing decision making in designing national screening, prevention programs, and molecular diagnostic tests. The accumulation of molecular data from different populations widen the scope of utilization of this information. Bleeding disorders are a heterogeneous group of clinically overlapping disorders. We analyzed the targeted sequencing data from ~1285 Saudi individuals in 17 blood and bleeding disorders genes, to determine the frequency of mutations and variants. We used a replication set of ~5000 local exomes to validate pathogenicity and determine allele frequencies. We identified a total of 821 variants, of these 98 were listed in HGMD as disease related variants and 140 were novel variants. The majority of variants were present in VWF, followed by F5, F8, and G6PD genes, while FGG, FGB, and HBA1 had the lowest number of variants. Our analysis generated a priority list of genes, mutations and novel variants. This data will have an impact on informing decisions for screening and prevention programs and in management of vulnerable patients admitted to emergency, surgery, or interventions with bleeding side effects.

COVID-19 in a pregnant patient with beta-thalassemia major: A case report

Further studies are needed on this unique population to better manage them and increase their chances of normal pregnancy and fewer complications and more favorable outcomes.

Low back pain in beta thalassemia major revealing sacral extramedullay hematopoeisis: A case report

Extramedullary hematopoiesis (EMH) is a well-known complication of beta thalassemia major and frequently occurs in typical sites such as liver or spleen. However, when presenting in unusual sites as sacrum, other diagnosis should be excluded by histopathology prior to deciding on treatment plan.

Thalassemia and Priapism: A Literature Review of a Rare Association

Thalassemia is a hematologic disorder caused by genetic mutation resulting in impaired hemoglobin chain production. Patients with thalassemia commonly experience complications such as anemia, blood transfusion-related issues, hepatic or cardiac involvement, and psychosocial impacts. Rarely, priapism has been associated with thalassemia as an initial presentation or subsequently occurring at any time in the disease course. Our literature review summarizes the reported cases of thalassemia-associated priapism and delves into underlying mechanisms of its pathophysiology and appropriate management.

Genetic Variants Associated With Alzheimer Disease in the 22 Arab Countries: A Systematic Review

BACKGROUND AND AIMS

Alzheimer disease (AD) is a progressive and complex neurodegenerative disease. Approximately 70% of AD risk is attributed to genetic risk factors, including variants in amyloid precursor protein (APP), presenilin 1 (PSEN1), and presenilin 2 (PSEN2) genes. Several studies have revealed a considerable number of candidate loci and genes for AD among different ethnic populations. However, the outcomes of these studies have been inconsistent. In this study, we aimed to investigate the spectrum of variants that are associated with the onset and development of AD among 22 Arab countries.

METHODOLOGY

We systematically searched 4 literature databases (Science Direct, Scopus, PubMed, and Web of Science) from the date of inception until July 2020 using various search terms to obtain all the reported genetic data on Arab AD cases.

RESULTS

In total, 18 studies were included, comprising a total of 2173 individuals, of whom 888 were clinically diagnosed AD patients and were genetically tested for genes and variants associated with AD. A total of 27 variants in 8 genes were found to be associated with AD. Of these variants, 17 were unique to the Arab population and 10 were shared with other ethnic groups.

CONCLUSIONS

There is a dearth of studies on the genetics of AD in the Arab world. There seems to be distinctive genetic and clinical susceptibility profiles for Arab patients with AD.

Genetic polymorphisms associated with obesity in the Arab world: a systematic review

BACKGROUND

Obesity, one of the most common chronic health conditions worldwide, is a multifactorial disease caused by complex genetic and environmental interactions. Several association studies have revealed a considerable number of candidate loci for obesity; however, the genotype-phenotype correlations remain unclear. To date, no comprehensive systematic review has been conducted to investigate the genetic risk factors for obesity among Arabs.

OBJECTIVES

This study aimed to systematically review the genetic polymorphisms that are significantly associated with obesity in Arabs.

METHODS

We searched four literature databases (PubMed, Science Direct, Scopus, and Google Scholar) from inception until May 2020 to obtain all reported genetic data related to obesity in Arab populations. Quality assessment and data extraction were performed individually by three investigators.

RESULTS

In total, 59 studies comprising a total of 15,488 cases and 9,760 controls were included in the systematic review. A total of 76 variants located within or near 49 genes were reported to be significantly associated with obesity. Among the 76 variants, two were described as unique to Arabs, as they have not been previously reported in other populations, and 19 were reported to be distinctively associated with obesity in Arabs but not in non-Arab populations.

CONCLUSIONS

There appears to be a unique genetic and clinical susceptibility profile of obesity in Arab patients.