Thalass. Rep., Volume 13, Issue 3 (September 2023) – 4 articles

Sickle cell disease (SCD) is a complex genetic disorder associated with multiple clinical manifestations, including increased susceptibility to bacterial and viral infections. This review article presents a comprehensive analysis of the current literature obtained from various online databases focusing on the relationship between SCD and infections caused by specific pathogens, such as pneumonia- and influenza-causing pathogens, Escherichia coli, Staphylococcus aureus, parvovirus, and hepatitis viruses. We discuss the underlying mechanisms that contribute to the increased susceptibility of individuals with SCD to these infections, primarily related to the pathophysiology of variant hemoglobin (HbSS) and its impact on vascular occlusion, hemolysis, functional asplenia, and immune deficiency. Moreover, we highlight the significant burden of infections on SCD patients, particularly children under five years of age, where they are the leading cause of morbidity and mortality. Additionally, we address the challenges faced in attempts for reducing the global mortality rate associated with SCD, particularly in low-income countries, where factors such as increased pathogen exposure, co-morbidities like malnutrition, lower vaccination rates, and limited healthcare facilities contribute to the high disease burden. This review emphasizes the need for targeted interventions, improved healthcare access, vaccination programs, and infection prevention strategies to alleviate the impact of infections on individuals with SCD and reduce the global mortality rates associated with the disease. Full article

Thalassemia is one of the most prevalent genetic disorders worldwide and has previously been found to have an association with several physiological and organ complications. Several studies have found both its positive and inverse correlation with the glomerular filtration rate (GFR). Therefore, in this meta-analysis, we tried to assess the accurate correlation of β-thalassemia major (β-TM) with GFR. We searched in Google Scholar, PubMed, and ScienceDirect, and from the initial 96 articles, we finally included 12 studies. The quality and publication bias assessment confirmed that all the studies were of high to moderate quality with no publication bias. The main outcome of the mean difference (MD) was −6.94, 95%CI: −20.69, 6.80 (p < 0.00001), which indicated a negative correlation of the GFR with β-TM. The sensitivity analyses found one study to be a slight outlier, and reanalyzing the data excluding that study, an MD was achieved of −16.46, 95%CI: −26.81, −6.11 (p < 0.00001), which provides even stronger support for our main outcome. Our result determined that the GFR is generally higher in healthy people as compared to β-TM patients. Full article

β-thalassemia, a congenital genetic hematological disorder characterized by the decrease or absence of β-globin chains, leads to a decrease in levels of Hemoglobin A. The affected individuals can be categorized into two cohorts based on transfusion dependency: transfusion-dependent thalassemia (TDT) and non-transfusion-dependent thalassemia (NTDT). Remarkably, despite the primary pathology lying in β-globin chain depletion, β-thalassemia also exhibits an intriguing association with iron overload. Iron metabolism, a tightly regulated physiological process, reveals a complex interplay in these patients. Over time, both cohorts of β-thalassemic individuals develop iron overload, albeit through distinct mechanisms. Addressing the diverse complications that arise due to iron overload in β-thalassemic patients, the utilization of iron chelators has gained a lot of significance. With varying efficacies, routes of administration, and modes of action, different iron chelators offer unique benefits to patients. In the Indian context, three commercialized iron chelators have emerged, showcasing a high adherence rate to iron chelator-based treatment regimens among β-thalassemic individuals. In this review, we explore the intriguing connection between β-thalassemia and iron overload, shedding light on the intricate mechanisms at play. We delve into the intricacies of iron metabolism, unveiling the distinct pathways leading to iron accumulation in these patients. Additionally, the therapeutic efficacy of different iron chelators in managing iron overload complications is mentioned briefly, along with the guidelines for their usage in India. Through this comprehensive analysis, we aim to deepen our understanding of β-thalassemia and iron overload, paving the way for optimized treatment strategies. Ultimately, our findings provide valuable insights into improving the care and outcomes of individuals affected by β-thalassemia. Full article

Background: HCV infection is very common in multi-transfused β-thalassemia patients who need regular blood transfusions. Aim: The study was conducted to determine the epidemiology of HCV in multi-transfused β-thalassemia patients in West Bengal, India. Methods: Over a span of six years, blood samples were collected from HCV sero-reactive β-thalassemia patients and processed for viral RNA isolation followed by nested RT-PCR for qualitative viremia detection. The HCV genotype was determined by amplifying the partial HCV core gene by nested RT-PCR followed by DNA sequencing and NCBI genotyping tools. Phylogenetic and phylogeographic studies were performed with MEGA-X and BEAST software, respectively. Results: Out of 917 multi-transfused HCV sero-reactive β-thalassemia patients, 598 (65.21%) were HCV RNA positive while 250 (41.80%) had spontaneously cleared the virus. A significant percentage of male patients from rural areas (p = 0.042) and economically backward class (p = 0.002) were at higher risk of HCV infection. Female thalassemia patients and individuals belonging to ages 11–15 years had higher chances of spontaneous clearance. The most prevalent circulatory HCV genotype was 3a (78.26%) followed by 1b (12.04%). Phylogeographic analyses revealed that the 3a strains share genomic similarities with strains from Pakistan, Sri Lanka, and Thailand, whereas the 1b strains share similarities with strains from Thailand, Vietnam, Russia, and China. Uncommon HCV subtypes 3g and 3i were also detected. Conclusion: The high prevalence of HCV infection among β-thalassemia patients of West Bengal, India indicates NAT-based assays should be implemented for HCV screening in donor blood to eliminate HCV by 2030. Full article