Association between genotype and disease complications in Egyptian patients with beta thalassemia: A Cross-sectional study

Genetic Correlation of HBB, HFE and HAMP Genes to Endocrinal Complications in Egyptian Beta Thalassemia Major Patients

Iron loading is regarded as the primary cause of endocrine abnormalities in thalassemia major patients. Thus, the purpose of the current research was to explore the impact of thalassemia genotypes, hepcidin antimicrobial peptide (HAMP) and hereditary hemochromatosis (HFE) gene variants, and hepcidin expression on serum ferritin and endocrinal complications in thalassemia patients. The study comprised fifty beta-thalassemia cases and fifty age- and sex-matched controls. Genotyping of the Beta-globin gene (HBB), HAMP, and exon 2 of the HFE gene was performed using Sanger sequencing. C282Y (c.845G > A) variant of the HFE gene was determined by PCR-RFLP. Hepcidin mRNA expression was assessed by qRT-PCR. Biochemical and hormonal studies were done for all patients. Hypogonadism and short stature were found in 56% and 20% of the investigated cases, respectively. Molecular studies reported a statistically higher frequency of the HAMP variant c.-582A > G in thalassemic patients than controls. Significant downregulation of hepcidin expression was found in cases compared to healthy subjects that was significantly associated with short stature. Considering the thalassemia alleles, the IVSI.1G > A (β0) allele was statistically related to hypogonadism. Our results proposed that thalassemia genotypes and downregulated hepcidin expression were the potential risk factors for endocrinopathies in our cases. We also demonstrated an increased incidence of the HAMP promoter variant c.- 582A > G that might have a role in the pathogenesis of iron overload in thalassemic cases. Significant downregulation of hepcidin expression, that contributes to increased iron burden, could be used as a future therapeutic target in these patients.

Thalassemia-related complications in pediatric, adolescent, and young adult patients with transfusion-dependent thalassemia: A multicenter study in Thailand

INTRODUCTION

Management of transfusion-dependent thalassemia (TDT) can be challenging due to numerous potential disease-related complications and comorbidities in particular age groups. The objective of this study was to report thalassemia-related complications and risk factors in pediatric, adolescent, and young adult patients with TDT.

METHODS

A multicenter web-based registry was conducted in patients with TDT aged 25 years and younger from eight university hospitals covering all parts of Thailand. Factors significantly associated with each complication were analyzed by logistic regression methods.

RESULTS

Of 605 patients, 267 thalassemia-related complications were reported from 231 pediatric, adolescent, and young adult patients with TDT patients (38.2%). The most common complications were infections, followed by cholelithiasis and growth failure. Splenectomy and elevated pre-transfusion hemoglobin were statistically significant risk factors for infections (adjusted odds ratio [AOR] = 2.3, 95% confidence interval [CI]: 1.2-4.5, p-value = .01 and AOR = 1.5, 95% CI: 1.2-1.7, p-value < .005, respectively). There were two statistically significant risk factors conferred endocrinopathies, including older age (AOR = 1.06, 95% CI: 1.01-1.1, p-value = .01) and being male (AOR = 2.4, 95% CI: 1.4-4.0, p-value = .002).

CONCLUSION

Nearly 40% of the patients in this cohort had thalassemia-related complications. Periodic surveillance and optimal care for respective complications may minimize comorbidities in pediatric, adolescent, and young adult patients with TDT.

A Systematic Review and Meta-Analysis of Stature Growth Complications in β-thalassemia Major Patients

Background

Blood transfusion is a traditional treatment for β-thalassemia (β-thal) that improves the patients' anemia and lifespan, but it may lead to iron overload in parenchymal tissue organs and endocrine glands that cause their dysfunctions as the iron regulatory system can't excrete excess iron from the bloodstream.

Objective

To evaluate the prevalence of iron-related complications (short stature, growth retardation, and growth hormone deficiency) in β-thalassemia major (βTM) patients.

Methods

We performed an electronic search in PubMed, Scopus, and Web of Sciences to evaluate the prevalence of growth hormone impairment in β-thalassemia major (βTM) patients worldwide. Qualities of eligible studies were assessed by the Joanna Briggs Institute checklist for the prevalence study. We used Comprehensive Meta-Analysis (Version 2) to calculate the event rate with 95% CIs, using a random-effects model for all analyses.

Findings

Seventy-four studies were included from five continents between 1978 and 2019; 70.27% (Asia), 16.21% (Europe), 6.75% (Africa), 2.70% (America), 1.35% (Oceania), and 2.70% (Multicenter). The overall mean age of the participants was about 14 years. The pooled prevalence of short stature (ST) was 48.9% (95% CI 35.3-62.6) and in male was higher than female (61.9%, 95% CI 53.4-69.7 vs. 50.9%, CI 41.8-59.9). The pooled prevalence of growth retardation (GR) was 41.1% and in male was higher than in female (51.6%, 95% CI 17.8-84 vs. 33.1%, CI 9.4-70.2). The pooled prevalence of growth hormone deficiency (GHD) was 26.6% (95% CI 16-40.8).

Conclusion

Our study revealed that near half of thalassemia patients suffer from growth impairments. However, regular evaluation of serum ferritin levels, close monitoring in a proper institute, suitable and acceptable treatment methods besides regular chelation therapy could significantly reduce the patients' complications.

Identification of Circulating Endocan-1 and Ether Phospholipids as Biomarkers for Complications in Thalassemia Patients

Despite advances in our knowledge and attempts to improve therapies, β-thalassemia remains a prevalent disorder with increased risk for the development of cardiomyopathy. Using an untargeted discovery-based lipidomic workflow, we uncovered that transfusion-dependent thalassemia (TDT) patients had a unique circulating lipidomic signature consisting of 387 lipid features, allowing their significant discrimination from healthy controls (Q-value < 0.01). In particular, TDT patients had elevated triacylglycerols and long-chain acylcarnitines, albeit lower ether phospholipids or plasmalogens, sphingomyelins, and cholesterol esters, reminiscent of that previously characterized in cardiometabolic diseases resulting from mitochondrial and peroxisomal dysfunction. Discriminating lipid (sub)classes correlated differentially with clinical parameters, reflecting blood (ether phospholipids) and iron (cholesterol ester) status or heart function (triacylglycerols). We also tested 15 potential serum biomarkers related to cardiometabolic disease and found that both lipocalin-2 and, for the first time, endocan-1 levels were significantly elevated in TDT patients and showed a strong correlation with blood parameters and three ether diacylglycerophosphatidylcholine species. In conclusion, this study identifies new characteristics of TDT patients which may have relevance in developing biomarkers and therapeutics.

Complications and Challenges in the Management of Iraqi Patients with β-Thalassemia Major: A Single-center Experience

OBJECTIVES

We sought to assess the complications and challenges facing the management of β-thalassemia major (β-TM) in Iraq.

METHODS

A total of 150 consecutive patients with β-TM who were registered at a main thalassemia center in Northern Iraq were enrolled in the study. The patients had their records reviewed, were clinically evaluated, and investigated for various complications.

RESULTS

Our patient cohort had a median age of 13 years (range: 1-35 years) and a male to female ratio of 1:1.2. Their median serum ferritin was 2762 µg/L, all were on regular transfusions, 94.7% were on chelation therapy, and 38.0% were splenectomized. Pre-transfusion hemoglobin levels were 3 9.0 g/dL in 38.7% of the patients. Short stature was encountered in 33.9% of those aged ≤ 20 years, and skeletal changes were noted in 50.7%. Iron overload associated complications, including hypogonadism, hypothyroidism, hypoparathyroidism, diabetes mellitus, and heart failure, were encountered in 52.8%, 7.3%, 3.3%, 3.3%, and 2.7%, respectively. Hepatitis C virus (HCV) antibodies were detectable in 35.3%, while HIV antibodies and hepatitis B surface antigen were not detectable in any. Patients with diabetes mellitus, heart failure, HCV antibodies, and hypoparathyroidism were significantly older than those without these complications. Hypogonadism was the only complication associated with significantly higher serum ferritin levels. Hypogonadism, heart failure, HCV antibodies, and diabetes were significantly more frequent among the splenectomized patients.

CONCLUSIONS

The management of β-TM in this cohort of Iraqi patients is still suboptimal, and the need to ensure timely transfusions and optimize chelation, as well as a more robust iron overload assessment, should be underscored.

Genotype/Phenotype Correlation of β-Thalassemia in Syrian Patients: A Cross-Sectional Study

β-Thalassemia (β-thal) is an inherited blood disorder caused by reduced or absent synthesis of β-globin chains leading to imbalance of globin chain synthesis. β⁰-Thalassemia (β⁰-thal), refers to the complete absence of β-globin chain production on the affected allele. β⁺-Thalassemia (β⁺-thal) refers to alleles with some residual production of β-globin chain. We studied the correlation of genotype/phenotype of β-thal disease in Syrian patients. A cross-sectional study was carried out on 260 patients with β-thal. Genotyping was determined by a DNA sequencing technique. Routine investigations were performed to assess the complete blood count (CBC), serum ferritin, Hb A₂ and Hb F levels. We found that the β⁰/β⁰ genotype was the most common in our patients followed by β⁺/β⁺ and β⁰/β⁺. Patients with β⁰/β⁰ received transfusions at an earlier age and more frequently when compared to those with β⁰/β⁺ and β⁺/β⁺ genotypes. Moreover, patients with β⁰/β⁰ had higher levels of Hb F and lower levels of Hb A₂ compared to those with β⁰/β⁺ and β⁺/β⁺ genotypes. All patients with β-thal intermedia (β-TI) carry the β⁺/β⁺ genotype, while all patients with β⁰/β⁰ and β⁰/β⁺ genotypes presented with transfusion-dependent β-thal major (β-TM).