Sickle cell disease: when and how to transfuse

Chronic automated red cell exchange therapy for sickle cell disease

BACKGROUND

The data to support chronic automated red cell exchange (RCE) in sickle cell disease (SCD) outside of stroke prevention, is limited, especially in adults.

STUDY DESIGN AND METHODS

A retrospective analysis was conducted of patients with SCD who were referred for chronic RCE at our institution over a 10-year period. Data that were evaluated included patient demographics, referral indications, and procedural details (e.g., vascular access, adverse events, etc.). In a subanalysis, the number of annual acute care encounters during 3 years of chronic RCE was compared with that in the year preceding the first RCE.

RESULTS

A total of 164 patients were referred for chronic RCE: median age was 28 years (interquartile range [IQR] = 22-36) at referral and 60% were female. Seventy (42.6%) were naïve to chronic transfusion (simple or RCE) prior to referral. The leading indications for referral were refractory pain (73/164, 44.5%) and iron overload (57/164, 34.7%). A total of 5090 procedures occurred during the study period (median = 19, IQR = 5-45). Of the 138 patients who had central vascular access, 8 (6%) and 16 (12%) had ≥1 central-line-related thrombosis and/or infection, respectively. Of those who were not RBC alloimmunized at initiation of RCE, 12/105 (11.4%) developed new antibodies during chronic RCE. In those 30 patients who were adherent to therapy for 3 years, there was no significant difference in acute care encounters following initiation of RCE.

CONCLUSION

Prospective clinical trials are needed to determine which patients are most likely to benefit from chronic RCE and refine selection accordingly.

Sickle cell disease in Australia: a snapshot from the Australian Haemoglobinopathy Registry

BACKGROUND

Sickle cell disease (SCD) is the most common monogenic disorder worldwide. In deoxygenated conditions, the altered beta chain (haemoglobin S [HbS]) polymerises and distorts the erythrocyte, resulting in pain crises, vasculopathy and end-organ damage. Clinical complications of SCD cause substantial morbidity, and therapy demands expertise and resources. Optimising care for patients and planning resource allocation for the future requires an understanding of the disease in the Australian population. The Australian Haemoglobinopathy Registry (HbR) is a collaborative initiative of specialist centres collating and analysing data on patients with haemoglobin disorders.

AIMS

To provide a snapshot of SCD in Australia over a 12-month period based on data from the HbR.

METHODS

Patients with a clinically significant sickling disorder across 12 clinical sites were included for analysis. Data include demographic and diagnostic details, as well as details of the clinical management of the condition over a 12-month period.

RESULTS

Data on 359 SCD patients demonstrate a shift in the demographic of patients in Australia, with a growing proportion of sub-Saharan African ethnicities associated with the HbSS genotype. Acute and chronic complications are common, and patients require significant outpatient and inpatient support. Prevalence of disease complications and therapeutic trends are in keeping with other high-income countries.

CONCLUSIONS

This study provides the first national picture of SCD in Australia, describing the characteristics and needs of SCD patients, elucidating demand for current and novel therapy and facilitating the planning of services for this vulnerable population.

Pediatric Moyamoya Revascularization Perioperative Care: A Modified Delphi Study

BACKGROUND

Surgical revascularization decreases the long-term risk of stroke in children with moyamoya arteriopathy but can be associated with an increased risk of stroke during the perioperative period. Evidence-based approaches to optimize perioperative management are limited and practice varies widely. Using a modified Delphi process, we sought to establish expert consensus on key components of the perioperative care of children with moyamoya undergoing indirect revascularization surgery and identify areas of equipoise to define future research priorities.

METHODS

Thirty neurologists, neurosurgeons, and intensivists practicing in North America with expertise in the management of pediatric moyamoya were invited to participate in a three-round, modified Delphi process consisting of a 138-item practice patterns survey, anonymous electronic evaluation of 88 consensus statements on a 5-point Likert scale, and a virtual group meeting during which statements were discussed, revised, and reassessed. Consensus was defined as ≥ 80% agreement or disagreement.

RESULTS

Thirty-nine statements regarding perioperative pediatric moyamoya care for indirect revascularization surgery reached consensus. Salient areas of consensus included the following: (1) children at a high risk for stroke and those with sickle cell disease should be preadmitted prior to indirect revascularization; (2) intravenous isotonic fluids should be administered in all patients for at least 4 h before and 24 h after surgery; (3) aspirin should not be discontinued in the immediate preoperative and postoperative periods; (4) arterial lines for blood pressure monitoring should be continued for at least 24 h after surgery and until active interventions to achieve blood pressure goals are not needed; (5) postoperative care should include hourly vital signs for at least 24 h, hourly neurologic assessments for at least 12 h, adequate pain control, maintaining normoxia and normothermia, and avoiding hypotension; and (6) intravenous fluid bolus administration should be considered the first-line intervention for new focal neurologic deficits following indirect revascularization surgery.

CONCLUSIONS

In the absence of data supporting specific care practices before and after indirect revascularization surgery in children with moyamoya, this Delphi process defined areas of consensus among neurosurgeons, neurologists, and intensivists with moyamoya expertise. Research priorities identified include determining the role of continuous electroencephalography in postoperative moyamoya care, optimal perioperative blood pressure and hemoglobin targets, and the role of supplemental oxygen for treatment of suspected postoperative ischemia.

Total hip replacement among sickle cell patients in a low-income country-Yemen

PURPOSE

Sickle cell patients presented with progressive hip pain and limitation of daily activities, as evidenced by low preoperative hip scores and failed conservative therapy. Management of femoral head avascular necrosis (AVN) using total hip replacement (THR) in sickle cell disease (SCD) is widespread in developed countries, but it is still in its initiation stage in developing countries. The outcome of using cementless THR among SCD patients is still unknown with lack of published studies from regional countries. This study aimed to evaluate the outcome of using cementless primary THR among patients with sickle cell disease with end-stage hip avascular necrosis in Yemen.

METHODS

Thirty cementless primary total hip arthroplasty (THA) were performed for AVN of the femoral head in 27 sickle cell patients, at Al.-Thawra Modern General Hospital-Sana'a, Yemen, from January 2018 to December 2022.

RESULTS

The mean age of the patients was 27 ± five years (ranged 18-37 years) with a male to female ratio was 3:1. Steinberg staging for hip AVN was stage IV, one patient (3%); stage VI, thirteen patients (45%); and stage V, sixteen patients (51%). THR was on right side 14 (52%), left side 10 (37%), and bilateral 3 (11%). The implant used was ceramic on polyethylene acetabular liner. All patients showed improvement in Harris hip score from preoperative mean hip score was 25 ± 8 points to postoperative mean hip score was 88 ± 6 points at the last follow-up. Mean of the length of stay in hospital was 12.7 ± eight days (ranged from 4 to 32 days); the mean operating time was 107 ± 23 min. Three cases had superficial wound infection; four patients had five intraoperative fractures; two cases had pulmonary complications; one case had abdominal crisis. All patients had postoperative leg length discrepancy less than 2 cm. None had deep infection, nerve injury, wound hematoma, aseptic loosing, dislocation, DVT, heterotopic ossification, or death.

CONCLUSION

THR in SCD has a good outcome using cementless THA with a low rate of complication in Yemen, a developing country.

Acute Liver Failure With Liver Enzymes >5,000 in Sickle Cell Disease

Sickle cell disease is a hemoglobinopathy often complicated by painful vaso-occlusive episodes, acute chest syndrome, stroke, and myocardial infarction. Sickle cell intrahepatic cholestasis (SCIC) is a rare and potentially fatal complication of sickle cell disease. SCIC is thought to involve progressive hepatic injury due to sickling within sinusoids. We present the case of a young patient with SCIC and acute liver failure, requiring prompt treatment with exchange transfusion. Our case describes features that should raise suspicion for hepatic failure in SCIC and highlights exchange transfusion as a successful management approach in similar patients with an otherwise high risk of mortality.

Managing sickle cell disease and related complications in pregnancy: results of an international Delphi panel

ABSTRACT

Data to guide evidence-based management of pregnant people with sickle cell disease (SCD) are limited. This international Delphi panel aimed to identify consensus among multidisciplinary experts for SCD management during pregnancy. The 2-round Delphi process used questionnaires exploring 7 topics (antenatal care, hydroxyurea use, transfusion, prevention of complications, treatment of complications, delivery and follow-up, and bottlenecks and knowledge gaps) developed by a steering committee. Thirteen panelists (hematologists, physiologists, obstetricians, maternal fetal medicine, and transfusion medicine physicians) from the United States, the United Kingdom, Turkey, and France completed the first survey; 12 panelists completed the second round. Anonymized responses were collected and summarized by a contract research organization (Akkodis Belgium). Consensus and strong consensus were predefined as 75% to 90% (9-10 of 12) and >90% (≥11 of 12) of panelists, respectively, agreeing or disagreeing on a response to a predefined clinical scenario or statement. In several areas of SCD management, consensus was achieved: experts recommended performing at least monthly multidisciplinary antenatal follow-up, administering prophylactic aspirin for preeclampsia prevention between gestational weeks 12 and 36, initiating prophylactic transfusion therapy in certain cases, or choosing automated red blood cell exchange over other transfusion methods for patients with iron overload or severe acute chest syndrome. No consensus was reached on several topics including the prophylactic aspirin dose, indications for starting infection prophylaxis, routine use of prophylactic transfusions, or use of prophylactic transfusions for preventing fetal complications. These recommendations could inform clinical care for patients with SCD who are pregnant in the absence of large clinical trials involving this population; the identified knowledge gaps can orient future research.

Hydroxyurea for secondary stroke prevention in children with sickle cell anaemia: a systematic review of clinical evidence and outcomes

Background

Stroke remains one of the leading complications of sickle cell anaemia (SCA) in children. Traditionally, SCA treatment focused on symptom relief. However, the high incidence of strokes in children has prompted a reevaluation of treatment, particularly hydroxyurea, for secondary stroke prevention. This study assesses hydroxyurea's effectiveness and safety in preventing secondary strokes in paediatric SCA patients.

Methods

This systematic review followed a pre-defined protocol registered with PROSPERO. Comprehensive searches were conducted across PubMed, Embase, Scopus, MEDLINE, Google Scholar, and the Cochrane Library up to August 2023. Studies were included involving paediatric SCA patients at risk of secondary stroke, assessing hydroxyurea as the primary intervention.

Results

A total of six studies meeting inclusion criteria were included. The effectiveness of hydroxyurea in preventing secondary strokes, with variable responses reported across studies. Adverse effects, including mild neutropenia, are associated with hydroxyurea treatment but with variability in reported toxicity levels.

Conclusion

Hydroxyurea holds promise in preventing recurrent strokes in children with SCA, though its efficacy and safety profiles vary among individuals. Optimal dosages and treatment durations require further investigation, necessitating vigilant monitoring of haematological parameters. Future research should refine dosing strategies, consider individual patient characteristics, assess long-term effects, and explore ancillary benefits beyond stroke prevention.

Compare the Efficacy and Safety of Deferoxamine, Deferasirox, and Deferiprone in Patients With Sickle Cell Disease or Transfusion-Dependent Anemia: A Network Meta-Analysis of Randomized Control Trials

This network meta-analysis was conducted with the aim of comparing the efficacy and safety of deferiprone (DFP), deferasirox (DFX), and deferoxamine (DFO) in individuals with sickle cell disease (SCD) or transfusion-dependent anemia. This systematic review and meta-analysis adhered to the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA)" guidelines. The search was conducted on electronic databases, including PubMed, CINAHIL, and EMBASE, from the inception of databases to January 10, 2024. Outcomes assessed in this study included a change in liver iron concentration (LIC) and a change in ferritin from baseline. For safety analysis, adverse events were compared among three treatment groups. A total of five studies were included in this meta-analysis. The pooled analysis showed that the change in LIC and serum ferritin from baseline was not significantly different in patients with SCD or other anemias. In terms of adverse events, deferiprone was the safest among all. In conclusion, deferiprone demonstrated noninferiority to deferoxamine and deferasirox in measures of iron load, presenting a viable treatment option. Safety outcomes revealed deferasirox carried a higher risk of adverse events compared to deferiprone, supporting its favorable safety profile.

Cardiovascular complications of sickle cell disease: A primer for the general clinician

Sickle cell disease (SCD) is the most common hereditary hemoglobinopathy and mainly affects individuals of African ancestry. As survival has improved especially in high-income countries, increased rates of cardiopulmonary complications such as pulmonary hypertension, heart failure with diastolic dysfunction, and sudden death are encountered in clinical practice. These complications are the leading causes of morbidity and mortality as these individuals survive into adulthood. Understanding the need for, early identification, timely intervention, and implementation of preventive strategies are critical in reversing this trend and improving quality of life and survival rates. This manuscript aims to provide a comprehensive review of the pathogenesis of cardiovascular complications associated with sickle cell disease and equip the clinician with tools to facilitate the early diagnosis and management of patients with SCD as increasing numbers survive into adulthood.

Prevalence and cost of sickle cell disease in France: real-world analysis using data from the Echantillon Généraliste des Bénéficiaires

Sickle cell disease (SCD) is a genetic disorder of the hemoglobin resulting in chronic anemia, hemolysis, and vaso-occlusions. Its treatment mostly relies on hydroxycarbamide, transfusions, and stem cell transplantation. This study aimed at describing the epidemiology and management of SCD in adolescent and adult patients in France. This was a retrospective study performed among SCD patients aged ≥12 years between 2016 and 2018 and controls. SCD patients were matched on a 1:3 ratio with a group of individuals with no diagnosis of SCD, referred as control group. The matching of SCD patients and controls was a direct matching based on age, sex, CMU-c status (which corresponds to free-of-charge complementary coverage for people with low resources) and geographical region of residence. SCD patients and their matched controls were followed-up for the same amount of time by adjusting controls' follow-up period to that of the associated patients. This study used claims data from the French representative 1/97th sample of health data system. The main outcomes were the patients' characteristics and treatments received, healthcare consumptions and related costs among SCD cases and controls. Between 2016 and 2018, 151 patients with ≥6 months of follow-up were identified out of the total population of 732,164 individuals. SCD prevalence extrapolated to the entire population [95% CI] was 19,502 [19,230, 19,778] in 2018. The median (Q1-Q3) age at inclusion date was 37.0 (25.0-48.0) years, with 69.5% of patients being female. The mean (SD) reimbursed cost over follow-up was €24,310 (89,167), mostly represented by hospitalization costs accounting for €21,156 (86,402). A switch in SCD management was observed with age, as younger patients presented more frequent hospitalizations and acute procedures, while older ones had more frequent medical visits and paramedical care. Mean (SD) annual costs were €25,680 (91,843) and vs. €3,227 (23,372) for patients and controls, respectively (p < 0.001), representing an extra cost of almost €150 million over the entire SCD population. This study highlighted the important costs related to SCD and the related medical need with treatment alternatives, which could be filled by the emergence of new therapies.

Severity and burden of sickle cell disease in France: a nationwide real-world study

The burden of sickle cell disease (SCD) in France has been difficult to apprehend due to the paucity of reliable nationwide epidemiological data. We aimed to describe the epidemiology of SCD and evaluate its burden and costs. Patients with SCD and most severely affected patients were identified between 2012 and 2018 from the French National Health Data System database (SNDS, Système national des données de santé). Outcomes of interest included rates of acute and chronic complications, healthcare resource utilization and associated costs, and were compared in subpopulations of patients before and after hematopoietic stem cell transplantation, initiating hydroxyurea or a chronic transfusion program. Between 2012 and 2018, 22,619 patients with SCD were identified, among which 4,270 patients were defined as most severely affected. Rates of vaso-occlusion episodes and acute chest syndrome were 86.29 (95% confidence interval [CI]: 85.75-86.83] and 12.90 (95% CI: 12.69-13.11) per 100 person years in the study population and 166.9 (95% CI: 165.4- 168.4) and 22.71 (95% CI: 22.16-23.27) per 100 person years in most severely affected patients. Median (Q1-Q3) annualized total costs were €5,073.63 (range, €1,633.74-14,000.94) and €13,295.67 (range, €5,754.67-26,385.23) in the study population and most severely affected patients. Median annualized costs were ten times lower after treatment intensification for hematopoietic stem cell transplantation (€29,011.75 vs. €2,465.98; P<0.001), they slightly decreased after hydroxyurea initiation (€13,057.79 vs. €12,752.44; P=0.003) and were five times higher after chronic transfusion program initiation (€4,643.11 vs. €22,715.85; P<0.001). SCD still places a significant demand on health resources, even after therapeutic intensification.

Impact and burden of sickle cell disease in critically ill obstetric patients in a high dependency unit in Sierra Leone-a registry based evaluation

INTRODUCTION

Sickle cell disease (SCD) in pregnancy is associated with worse maternal and neonatal outcomes. There is limited available data describing the burden and outcomes of critically ill obstetric patients affected by SCD in low-income settings.

OBJECTIVES

We aimed to define SCD burden and impact on mortality in critically-ill obstetric patients admitted to an urban referral hospital in Sierra Leone. We hypothesized that SCD burden is high and independently associated with increased mortality.

METHODS

We performed a registry-based cross-sectional study from March 2020 to December 2021 in the high-dependency unit (HDU) of Princess Christian Maternity Hospital PCMH, Freetown. Primary endpoints were the proportion of patients identified in the SCD group and HDU mortality. Secondary endpoints included frequency of maternal direct obstetric complications (MDOCs) and the maternal early obstetric warning score (MEOWS).

RESULTS

Out of a total of 497 patients, 25 (5.5%) qualified to be included in the SCD group. MEOWS on admission was not different between patients with and without SCD and SCD patients had also less frequently reported MDOCs. Yet, crude HDU mortality in the SCD group was 36%, compared to 9.5% in the non SCD group (P < 0.01), with an independent association between SCD group exposure and mortality when accounting for severity on admission (hazard ratio 3.40; 95%CI 1.57-7.39; P = 0.002). Patients with SCD had a tendency to longer HDU length of stay.

CONCLUSIONS

One out of twenty patients accessing a HDU in Sierra Leone fulfilled criteria for SCD. Despite comparable severity on admission, mortality in SCD patients was four times higher than patients without SCD. Optimization of intermediate and intensive care for this group of patients should be prioritized in low-resource settings with high maternal mortality.

The implementation of automated red blood cell exchange (erythrocytapheresis) as a treatment modality in sickle cell disease patients: Single center experience

BACKGROUND

Improvements of health infrastructure, preventive care and clinical management is important to reduce the morbidity and mortality of sickle cell disease (SCD).

OBJECTIVE

This prospective, investigator-initiated non-randomized open-label intervention, single centre study describes the implementation of the automated erythrocytapheresis in low-middle income country as a treatment modality for SCD patients to improve the standard of care and highlights its benefits and challenges.

METHODOLOGY

Eligible patients with SCD who had overt stroke, abnormal/conditional transcranial doppler (TCD), or other indications were subjected to regular automated erythrocytapheresis program.

RESULTS

From 18th Dec 2017 till 17th Dec 2022, 21 subjects were enrolled; seventeen (80.9 %) were Egyptian and four (19.1 %) were non-Egyptian (three Sudanese and one Nigerian). Totalling 133 sessions had been performed mainly in working hours with fluctuating frequency per month. All sessions maintained isovolumic status and were performed using central venous access. The target HbS concentration was set from the start; the mean final FCR % fraction was 51, most of the session (n = 78, 58.7 %) were able to achieve target FCR. The majority of session pass smoothly with no adverse event (n = 81, 60.9 %), except for certain challenges as shortage of the required blood (n = 38), hypotension (n = 2), hypocalcaemia (n = 2).

CONCLUSION

Automated erythrocytapheresis is safe and effective modality for management of patients with sickle cell disease.

Outcomes and long-term effects of hematopoietic stem cell transplant in sickle cell disease

INTRODUCTION

Hematopoietic stem cell transplant (HSCT) is the only readily available curative option for sickle cell disease (SCD). Cure rates following human leukocyte antigen (HLA)-matched related donor HSCT with myeloablative or non-myeloablative conditioning are >90%. Alternative donor sources, including haploidentical donor and autologous with gene therapy, expand donor options but are limited by inferior outcomes, limited data, and/or shorter follow-up and therefore remain experimental.

AREAS COVERED

Outcomes are improving with time, with donor type and conditioning regimens having the greatest impact on long-term complications. Patients with stable donor engraftment do not experience SCD-related symptoms and have stabilization or improvement of end-organ pathology; however, the long-term effects of curative strategies remain to be fully established and have significant implications in a patient's decision to seek therapy. This review covers currently published literature on HSCT outcomes, including organ-specific outcomes implicated in SCD, as well as long-term effects.

EXPERT OPINION

HSCT, both allogeneic and autologous gene therapy, in the SCD population reverses the sickle phenotype, prevents further organ damage, can resolve prior organ dysfunction in both pediatric and adult patients. Data support greater success with HSCT at a younger age, thus, curative therapies should be discussed early in the patient's life.

The Role of Antiplatelet in the Management of Sickle Cell Disease Patients

Sickle cell disease (SCD) is a genetic disorder characterized by abnormal hemoglobin, leading to red blood cell deformities and subsequent vaso-occlusive events. Platelet activation and adhesion play a significant role in the pathophysiology of SCD, contributing to the development of complications such as vaso-occlusive events, stroke, acute chest syndrome, and other manifestations. Antiplatelet therapy has emerged as a potential strategy to mitigate these complications by modulating the platelet function and reducing thrombotic events. This review article provides an overview of antiplatelet therapy's role in managing SCD patients. It discusses the pathophysiological abnormalities in the platelet function in SCD, the rationale for antiplatelet therapy, and the evidence supporting its use in various clinical scenarios. The article explores aspirin as the primary antiplatelet agent in SCD, including its mechanism of action, dosing considerations, and efficacy and safety data. Additionally, it highlights other antiplatelet agents, such as clopidogrel, prasugrel, ticagrelor, and emerging therapies under investigation. Clinical applications of antiplatelet therapy in primary and secondary prevention and the management of acute chest syndrome and other SCD complications are also discussed. Safety considerations are emphasized, including bleeding risk assessment, monitoring, and patient selection for antiplatelet therapy. Finally, the review highlights future research and clinical practice directions, including the development of novel antiplatelet agents, combination therapies, and the integration of antiplatelet therapy with other SCD treatments. Overall, this review provides a comprehensive understanding of the current role of antiplatelet therapy in SCD management, the challenges faced, and future directions for improving patient outcomes.

Acute Chest Syndrome in Sickle Cell Disease

Acute chest syndrome (ACS) is the leading cause of mortality among individuals with sickle cell disease (SCD) accounting for 25% of all deaths. The etiologies and clinical manifestations of ACS are variable among children and adults, with a lack of clear risk stratification guidelines for the practicing clinician. In addition, the management of ACS is based on limited evidence and is currently guided primarily by expert opinion. This manuscript reviews the pathophysiology, risk factors, and current management strategies for ACS through a review of published data on this subject between 1988 and 2022. Blood transfusion is often used as a therapeutic intervention for ACS to increase blood's oxygen-carrying capacity and reduce complications by reducing hemoglobin S (HbS) percentage, based on the very low quality of the evidence about its efficacy. The benefit of RBC transfusion for ACS has been described in case series and observational studies, but randomized studies comparing simple transfusion vs. exchange transfusions for ACS are lacking. In this review, we conclude that the development of clinical and laboratory risk stratification is necessary to further study an optimal management strategy for individuals with ACS to avoid transfusion-related complications while minimizing mortality.

Correlation of Transfusion Dependence and Its Associated Sequelae to Hematological and Biochemical Parameters in Patients With Sickle Cell Disease and Beta Thalassemia Major in Khobar: A Retrospective Study

Sickle cell disease (SCD) and beta thalassemia major (βTM) are multisystemic, genetically inherited diseases. They are caused by mutations of hemoglobin, which ultimately cause abnormal functioning of the red blood cells. The morbidity and mortality rates of these diseases are significant, as they may result in severe complications, some of which are quite fatal; hence, early diagnosis and treatment are crucial. The purpose of this study is to collect patients' data in terms of their manifestations and overall clinical picture and correlate them to the laboratory parameters with emphasis on their transfusion dependence and its sequelae in King Fahd Hospital of the University (KFHU), Al-Khobar, Saudi Arabia. After obtaining ethical approval from the institutional review board and in collaboration with the blood bank, patients' data were retrospectively collected from the hospital's database and categorized into two disease groups. Accordingly, data related to the biological and demographic information, clinical picture pattern, laboratory investigations, and therapeutic measures, with emphasis on blood transfusion as a treatment option, were gathered and analyzed. Eventually, the aforementioned data aspects were assessed for the probability of correlations, which were proven to be present to some level as an answer to our cohort study's question. Such findings, which will be depicted later in this study, might represent a ground for having a more comprehensive and extensive approach in terms of the general evaluation of patients with SCD and βTM based on the established level of correlation. During the course of conducting our research, we encountered some limitations, including the sample size and scarce data available during the process of data collection.

Timing matters: An analysis of the relationship between red cell transfusion timing and hospitalization outcomes in sickle cell crisis patients using the National Inpatient Sample database

Vaso-occlusive pain crisis is a debilitating complication of sickle cell disease (SCD) and it is the most common cause of hospitalization among these individuals. We studied the inpatient outcomes among patients admitted with sickle cell crisis based on the timing of red blood cell transfusion. In this retrospective study, we used the United States National Inpatient Sample (NIS) data for the year 2019, to identify adult patients hospitalized with the principal diagnosis of sickle cell crisis who received simple red blood cell transfusion during their hospitalization. Patients were divided into two groups. Those who received simple red cell transfusion within 24 hours of admission were classified as early transfusion. After adjusting for confounders, the mean adjusted length of stay for patients with early transfusion was significantly lower than those who received a late blood transfusion by 3.51 days (p-value < 0.001) along with a decrease in mean adjusted hospitalization charges and cost, by 25,487 and 4,505 United States Dollar (USD) respectively. The early red cell transfusion was also associated with a decrease in inpatient mortality, demonstrated by an adjusted odds ratio (aOR) of 0.19 (p-value 0.036), and a reduction in in-hospital sepsis, with an aOR of 0.28 (p-value < 0.001), however, no statistically significant difference was found between the two groups regarding acute respiratory failure requiring intubation, vasopressors requirement, acute kidney injury requiring dialysis and intensive care unit (ICU) admission. We recommend timely triage and reassessment to identify sickle cell crisis patients requiring blood transfusion. This intervention can notably affect the inpatient length of stay, resource utilization, and hospitalization outcomes.

Diverse Approaches to Gene Therapy of Sickle Cell Disease

Sickle cell disease (SCD) results from a single base pair change in the sixth codon of the β-globin chain of hemoglobin, which promotes aggregation of deoxyhemoglobin, increasing rigidity of red blood cells and causing vaso-occlusive and hemolytic complications. Allogeneic transplant of hematopoietic stem cells (HSCs) can eliminate SCD manifestations but is limited by absence of well-matched donors and immune complications. Gene therapy with transplantation of autologous HSCs that are gene-modified may provide similar benefits without the immune complications. Much progress has been made, and patients are realizing significant clinical improvements in multiple trials using different approaches with lentiviral vector-mediated gene addition to inhibit hemoglobin aggregation. Gene editing approaches are under development to provide additional therapeutic opportunities. Gene therapy for SCD has advanced from an attractive concept to clinical reality.

A conservative approach in finding compatible blood for a patient with sickle cell disease having multiple alloantibodies

BACKGROUND

Sickle cell disease (SCD) patients may develop multiple alloantibodies that pose problem in finding compatible blood for transfusion and require crossmatching with large number of blood.

AIM

The aim of the present study was to find compatible blood with reduced cost by adopting a conservative approach.

MATERIALS AND METHODS

A step-by-step approach using tube technique, antibodies in original serum, and the saved test supernatant (TS) in search of compatible blood for transfusion purposes.

RESULTS

32 years SCD patient grouped A with multiple antibodies required transfusion. A total of 641 red blood cell (RBC) units of groups A and O were crossmatched using serum and the TS by tube method. Of 138 units tested using the serum at 4°C, 124 units showed direct agglutination in the saline phase and the remaining 14 units were processed through low ionic strength solution (LISS)-IAT, of which 2 units were compatible even by the gel-IgG-card method. The TS, saved from the tests on serum, was used in an identical manner as that of the serum to screen additional 503 units by saline tube method at 4°C units showed direct agglutination of the RBCs of 428 units, hence were removed from inventory for this patient. The remaining 75 units were tested by the LISS-IAT-tube method at 37°C, of which 8 units were found compatible but only 2 units were clear compatible by the gel-IgG-card method. As such, 4 units compatible by the sensitive gel-IgG-card method were issued for transfusion purposes.

CONCLUSION

The new approach on using the saved TS consumed less of the patient's blood specimen, and the use of the tube method in screening and eliminating a large chunk of incompatible blood units has proved economical if compared with the use of the only gel-IgG-cards device in the entire maneuvering.

Managing the Cerebrovascular Complications of Sickle Cell Disease: Current Perspectives

The importance of protecting brain function for people with sickle cell disease (SCD) cannot be overstated. SCD is associated with multiple cerebrovascular complications that threaten neurocognitive function and life. Without screening and preventive management, 11% of children at 24% of adults with SCD have ischemic or hemorrhagic strokes. Stroke screening in children with SCD is well-established using transcranial Doppler ultrasound (TCD). TCD velocities above 200 cm/s significantly increase the risk of stroke, which can be prevented using chronic red blood cell (RBC) transfusion. RBC transfusion is also the cornerstone of acute stroke management and secondary stroke prevention. Chronic transfusion requires long-term management of complications like iron overload. Hydroxyurea can replace chronic transfusions for primary stroke prevention in a select group of patients or in populations where chronic transfusions are not feasible. Silent cerebral infarction (SCI) is even more common than stroke, affecting 39% of children and more than 50% of adults with SCD; management of SCI is individualized and includes careful neurocognitive evaluation. Hematopoietic stem cell transplant prevents cerebrovascular complications, despite the short- and long-term risks. Newer disease-modifying agents like voxelotor and crizanlizumab, as well as gene therapy, may treat cerebrovascular complications, but these approaches are investigational.

Hemoglobin and End-Organ Damage in Individuals with Sickle Cell Disease

Background

Sickle cell disease (SCD) is an inherited, chronic, multifaceted blood disorder. Patients with SCD develop anemia, which has been associated with end-organ damage (EOD).

Objectives

This retrospective, observational, repeated-measures study systematically characterizes the relationship between hemoglobin (Hb) level and EOD in adolescent and adult patients with SCD.

Methods

The study population comprised patients with SCD aged ≥12 years with available Hb data from a US provider-centric health care database. For each patient, each Hb value over time was included as a separate observation. Study outcomes-the onset of any new EOD, including chronic kidney disease, pulmonary hypertension, stroke, and leg ulcer-were ascertained during the 1-year period after each Hb assessment. The association between Hb levels and risk of new EOD was estimated using multivariable generalized estimating equations.

Results

A total of 16,043 unique patients with SCD contributed 44,913 observations. Adjusted odds of any EOD during the 1-year follow-up were significantly lower with higher Hb level. Risk reductions with higher Hb levels for chronic kidney disease, pulmonary hypertension, and leg ulcer were comparable. The risk of new EOD was significantly lower among adolescent and adult patients with higher Hb levels.

Conclusions

In patients with SCD, higher Hb levels are associated with a reduced risk of developing EOD. Therapeutic strategies that result in higher Hb levels may offer clinical and economic value for patients with SCD. (Curr Ther Res Clin Exp. 2023; 84:XXX-XXX).

Red Blood Cell Alloimmunization and Autoimmunization in Blood Transfusion-Dependent Sickle Cell Disease and β-Thalassemia Patients in Al-Ahsa Region, Saudi Arabia

Introduction

The risk of developing transfusion-related complications, especially alloimmunization, is an ongoing concern for transfusion-dependent patients. It is important to determine the rate of alloimmunization and autoimmunization in Al-Ahsa Region, Saudi Arabia, where sickle cell disease (SCD) and thalassemia incidence rates are the highest in Saudi Arabia.

Methods

A cross-sectional study was conducted to review the transfusion history of patients with SCD and thalassemia at the King Fahad Hospital (KFH) in Al-Ahsa, Saudi Arabia. 364 transfusion-dependent patients were included in this study.

Results

Alloimmunization rates in patients with SCD and thalassemia were 16.7% and 11.97%, respectively, while autoimmunization rates in patients with SCD and thalassemia were 5.3% and 0.7%, respectively. The most frequent alloantibodies among the study participants were against Kell, Rh blood group systems.

Conclusion

Blood transfusion-related alloimmunization and autoimmunization compromise the proper management of chronically transfused patients. Ideally, extended matched phenotyping should be implemented to prevent alloimmunization and reduce the risk of developing blood transfusion-related alloantibodies.

Blood Transfusion Vs. Hydroxyurea for Stroke Prevention in Children With Sickle Cell Anemia: A Systematic Review and Meta-Analysis

Sickle cell anemia (SCA) is a hereditary condition that can lead to severe complications in children such as acute coronary syndrome, splenic sequestration, renal failure, and stroke. Blood transfusion and hydroxyurea (HU) therapy are used to prevent stroke in children with sickle cell disease (SCD). Preliminary data show considerable variation and inconsistency in the use of these two therapeutic interventions. Therefore, this systematic review was carried out to compare the effects of blood transfusion to HU therapy in preventing stroke for children with sickle cell disease. There was an extensive literature search in reliable and authentic databases like PubMed, Medline, Scopus, Cochrane, and Science Direct to obtain relevant articles. This study used the standards and guidelines from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). During the systematic review, data were obtained focusing on the following parameters: the size of the sample in the study, the age of the subjects involved in the study, the type of Intervention, and the outcome. After an initial search of 163 papers, 25 studies were included. The results of the research give the first evidence that HU is effective in the treatment of cerebrovascular problems in children with SCD. However, it is unclear under what circumstances HU may prevent a second stroke. It can be concluded that children with SCA can effectively avoid primary strokes through chronic blood transfusions and HU.

Treatment patterns and burden of complications associated with sickle cell disease: A US retrospective claims analysis

Complications associated with sickle cell disease (SCD) that are highly impactful for patients but until recently have been less understood include priapism, nephropathy, and neurologic injury. We conducted a retrospective study using US administrative claims data from July 01, 2013 through March 31, 2020 to analyze incidence of these complications, SCD treatment patterns, and healthcare resource utilization (HCRU) and costs among 2524 pediatric and adult patients with SCD (mean [SD] age 43.4 [22.4] years). The most common treatments during follow-up were short-acting opioids (54.0% of patients), red blood cell transfusion (15.9%), and hydroxyurea (11.0%). SCD complications occurred frequently; in the overall population, the highest follow-up incidences per 1000 person-years were for acute kidney injury (53.1), chronic kidney disease (40.6), and stroke (39.0). Complications occurred across all age groups but increased in frequency with age; notably, acute kidney injury was 69.7 times more frequent among ages 65+ than ages 0-15 (p < 0.001). Follow-up per-patient-per-month HCRU also increased with age; however, all-cause healthcare costs were similarly high for all age groups and were driven primarily by inpatient stays. Patients with SCD across the age spectrum have a high burden of complications with the use of current treatments, suggesting unmet needs for treatment management.

Sickle Cell Disease in Children and Adolescents: A Review of the Historical, Clinical, and Public Health Perspective of Sub-Saharan Africa and Beyond

Sickle cell disease (SCD) is an umbrella term for a group of life-long debilitating autosomal recessive disorders that are caused by a single-point mutation (Glu→Val) that results in polymerization of hemoglobin (Hb) and reversible sickle-shape deformation of erythrocytes. This leads to increased hemolysis of erythrocytes and microvascular occlusion, ischemia-reperfusion injury, and tissue infarction, ultimately causing multisystem end-organ complications. Sickle cell anemia (HbSS) is the most common and most severe genotype of SCD, followed by HbSC, HbSβ⁰thalassemia, HbSβ+thalassemia, and rare and benign genotypes. Clinical manifestations of SCD occur early in life, are variable, and are modified by several genetic and environmental factors. Nearly 500 children with SCD continue to die prematurely every day, due to delayed diagnosis and/or lack of access to comprehensive care in sub-Saharan Africa (SSA), a trend that needs to be urgently reversed. Despite proven efficacy in developed countries, newborn screening programs are not universal in SSA. This calls for a consolidated effort to make this possible, through the use of rapid, accurate, and cheap point-of-care test kits which require minimal training. For almost two decades, hydroxyurea (hydroxycarbamide), a century-old drug, was the only disease-modifying therapy approved by the U.S. Food and Drug Administration. Recently, the list expanded to L-glutamine, crizanlizumab, and voxelotor, with several promising novel therapies in the pipeline. Despite its several limitations, hematopoietic stem cell transplant (HSCT) remains the only curative intervention for SCD. Meanwhile, recent advances in gene therapy trials offer a glimpse of hope for the near future, although its use maybe limited to developed countries for several decades.

Adverse events of red blood cell transfusions in patients with sickle cell disease

Blood transfusion is a common medical intervention for patients with sickle cell disease (SCD) and disease related complications. While patients with SCD are at risk for all transfusion related adverse events defined by the National Healthcare Safety Network (NHSN) Biovigilance Component Hemovigilance Module Surveillance Protocol, they are uniquely susceptible to certain adverse events. This review discusses risk factors, mitigation strategies, and management recommendations for alloimmunization, hemolytic transfusion reactions, hyperviscosity and transfusion-associated iron overload in the context of SCD.

Clinical outcome of pre-operative blood transfusion for sickle cell disease patients in post-operative complications

BACKGROUND

Preoperative blood transfusion for patients with sickle cell disease is a debatable topic and it can be lifesaving. Sickle cell disease patients are at high risk for vaso-occlusive crisis due to the large concentration of sickle hemoglobin (HgbS) in their blood. Despite the current extensive research into this disease, there is still no consensus over whether blood transfusion is a preferable preoperative modality among patients undergoing elective surgical procedures.

METHOD

A retrospective observational study, which enrolled 204 patients with Sickle cell disease who underwent surgery at King Fahad Hospital of the University (KFHU) over the last five years. The primary objective was to determine whether there is evidence that preoperative blood transfusion for SCD patients undergoing surgical procedures will reduce postoperative complications related to SCD.

RESULTS

A total of 204 patients were included, of which 30% had preoperative blood transfusion. Majority of patient 44% had undergone cholecystectomy. On multivariate logistic regression analysis, patients who did not undergo blood transfusion had significantly higher risk to develop post-operative SCD complications (OR=3.07, P value= 0.002). In addition, they had significantly prolonged hospitalization (OR= 2.22, P value= 0.08). In contrast, patients who received blood transfusion had lower risk for developing post-operative SCD related complications (OR=1.87, P value= 0.29), and decrease in the duration of hospitalization by (OR=0.49, P value= 0.045).

CONCLUSION

Our study showed that patients who had not undergo preoperative blood transfusion had higher risk to develop postoperative complications and prolonged hospital stay compared to those who underwent blood transfusion.

Reduction in seroprevalence of viral transfusion-transmitted infections in southwest Nigeria in children with sickle cell disease using an enhanced screening strategy

Blood transfusion is an integral component in the management of children and adults with sickle cell disease (SCD). Concerns about blood safety due to the high risk of bloodborne infections in sub-Saharan Africa limits the application of this cost-effective strategy in the management of individuals with SCD. In a single-centre, retrospective, longitudinal study in southwest Nigeria, we hypothesised that the use of stringent blood donor selection, along with very sensitive enzyme-linked immunosorbent assay (ELISA) screening methods would reduce transfusion-transmitted infections (TTIs). Among 45 002 eligible blood donors at the Lagos University Teaching Hospital in Nigeria, over a 5-year review period (2015-2019), the seroprevalence rate of viral TTIs was 9.83%. The seroprevalence rates for human immunodeficiency, hepatitis B, and hepatitis C viruses were 1.37%, 6.2%, and 2.25% respectively. Among 172 children with SCD, 71% (122/172) on regular blood transfusion and 29% (50/172) who had never been transfused or had less than two transfusions per lifetime, none acquired any TTIs using our enhanced screening approach during the study period. Thus, safe blood transfusion practices can be provided for children with SCD in sub-Saharan Africa with the use of stringent donor selection protocols and fourth-generation ELISA kits for TTI screening.

Management of acute chest syndrome in patients with sickle cell disease: a systematic review of randomized clinical trials

INTRODUCTION

Acute chest syndrome (ACS) accounts for the highest mortality in Sickle cell disease patients. Early diagnosis and timely management of ACS results in better outcomes. However, the effectiveness of most treatment modalities for ACS management has not been established.

AREAS COVERED

To review the treatment modalities management protocols and highlight the effectiveness of each option a literature search was done. Randomized controlled trials that assessed the efficacy of different treatment modalities in ACS management in SCD patients were chosen and reviewed.

EXPERT OPINION

11 randomized controlled trials were found that evaluated the efficacy of incentive spirometry, positive expiratory pressure device, intravenous dexamethasone, oral vs. intravenous morphine, inhaled nitric oxide, unfractionated heparin, and blood transfusion in the prevention or treatment of ACS. Although there are guidelines for ACS treatment, the available evidence is very limited to delineating the effectiveness of various interventions in ACS management. More high-quality studies and trials with a larger patient population can benefit this area to support the recommendations with stronger evidence.

The ektacytometric elongation Index (EI) of erythrocytes, validation of a prognostic, rheological biomarker for patients with sickle cell disease

OBJECTIVES

Validation of the measurement of erythrocyte deformability as a useful prognostic, rheological biomarker for patients with sickle cell disease (SCD).

METHODS

The degree of reduced deformability was based on the value of the maximum elongation index (EI_max ) of the deformability curve of an osmotic gradient ektacytometer. The performance of this technique was analytically and clinically validated by analysing 200 normal subjects and 100 patients with well-documented thalassemia's and Hb variants in relation to their clinical condition.

RESULTS

In this study, we show that EI_max is a reproducible parameter with a small inter-individual coefficient of (Biological) variation (CV)=1.6% and a small intra-individual CV=3.5%. We demonstrate that loss of deformability correlates with the clinical condition and the various mutations underlying sickle cell disease and thalassemia. For SCD patients, a strongly reduced EI_max with a cut-off =0.360 is a signal for future vaso-occlusive (VOC) events requiring hospitalisation with a specificity=85%, sensitivity=80%, PPV=81% and NPV=84% based on a ROC curve (AUC=0.89).

CONCLUSION

This study validated the clinical utility of EI_max as a prognostic marker for future clinical problems in individual high-risk SCD patients. In addition, EI_max may help to achieve an adequate personal transfusion policy for an optimal blood flow in anaemic patients with SCD.

Multifocal Osteonecrosis in a 3-Year-old Child With Sickle Beta Plus Thalassemia

Sickle beta+thalassemia is considered to be a mild form of sickle cell disease. However, some patients with mild disease can present with osteonecrosis. Here, we present a rare 3-year-old male who presented with acute pain, a baseline hemoglobin of 13 g/dL, who acutely developed multifocal osteonecrosis, and improved with partial exchange transfusion and hydroxyurea therapy.

Real-world effectiveness of voxelotor for treating sickle cell disease in the US: a large claims data analysis

BACKGROUND

Sickle cell disease (SCD) is a genetic disease that impacts patients' quality of life, healthcare costs, and life expectancy. Elevated sickle hemoglobin (HbS), which readily polymerizes, causes red blood cell sickling, leading to chronic hemolytic anemia and complications often requiring hospitalization and transfusions. In 2019, voxelotor, which inhibits HbS polymerization, was approved for SCD treatment.

OBJECTIVES

This study uses real-world evidence to assess voxelotor's effectiveness in SCD patients in typical clinical practice from 2019 to 2021 using a national medical claims database (N = 3128).

RESULTS

After initiating voxelotor, 60.8% of patients with available hemoglobin (Hb) laboratory data (n = 74) showed a Hb increase >1 g/dL. Mean transfusion rate per patient-year dropped 52% in patients with ≥1 transfusion before treatment (n = 190). In patients with ≥1 of the corresponding events (n = 1065), decreases were observed in mean vaso-occlusive crisis (VOC) frequency (-23%); mean VOC-related hospitalizations and length of stay (LOS) time (-34% and -30%, respectively); mean all-cause hospitalization and LOS time (-37% and -23%, respectively); outpatient visits (-10%); iron chelation use (-46%); and prescribed opioids (-13%).

CONCLUSION

These data align with randomized controlled trial results showing voxelotor improvements and support that voxelotor may lower transfusion and VOC rates in clinical practice.

Influence of Haptoglobin Polymorphism on Stroke in Sickle Cell Disease Patients

This review outlines the current clinical research investigating how the haptoglobin (Hp) genetic polymorphism and stroke occurrence are implicated in sickle cell disease (SCD) pathophysiology. Hp is a blood serum glycoprotein responsible for binding and removing toxic free hemoglobin from the vasculature. The role of Hp in patients with SCD is critical in combating blood toxicity, inflammation, oxidative stress, and even stroke. Ischemic stroke occurs when a blocked vessel decreases oxygen delivery in the blood to cerebral tissue and is commonly associated with SCD. Due to the malformed red blood cells of sickle hemoglobin S, blockage of blood flow is much more prevalent in patients with SCD. This review is the first to evaluate the role of the Hp polymorphism in the incidence of stroke in patients with SCD. Overall, the data compiled in this review suggest that further studies should be conducted to reveal and evaluate potential clinical advancements for gene therapy and Hp infusions.

Blood transfusion and iron overload in patients with Sickle Cell Disease (SCD): Personal experience and a short update of diabetes mellitus occurrence

The conventional treatment of β-thalassemia (β-TM) patients is based on the correction of anemia through regular blood transfusions and iron chelation therapy. However, allogeneic hematopoietic stem cell transplantation (HSCT) remains the only currently available technique that has curative potential. Variable frequency and severity of long-term growth and endocrine changes after conventional treatment as well as after HSCT have been reported by different centers. The goal of this mini-review is to summarize and update knowledge about long-term growth and endocrine changes after HSCT in patients with β-TM in comparison to those occurring in β-TM patients on conventional treatment. Regular surveillance, early diagnosis, treatment, and follow-up in a multi-disciplinary specialized setting are suggested to optimize the patient's quality of life (www.actabiomedica.it).

Perinatal outcomes in women with sickle cell disease: a matched cohort study from London, UK

There are limited data on contemporary outcomes for women with sickle cell disease (SCD) in pregnancy. We conducted a single-site matched cohort study, comparing 131 pregnancies to women with SCD between 2007 and 2017 to a comparison group of 1310 pregnancies unaffected by SCD. Restricting our analysis to singleton pregnancies that reached 24 weeks of gestation, we used conditional Poisson regression to estimate adjusted risk ratios (aRRs) for perinatal outcomes. Infants born to mothers with SCD were more likely to be small for gestational age [aRR 1·69, 95% confidence interval (CI) 1·13-2·48], preterm (aRR 2·62, 95% CI 1·82-3·78) and require Neonatal Unit (NNU) admission (aRR 3·59, 95% CI 2·18-5·90). Pregnant women with SCD were at higher risk of pre-eclampsia/eclampsia (aRR 3·53, 95% CI 2·00-6·24), more likely to receive induction of labour (aRR 2·50, 95% CI 1·82-1·76) and caesarean birth (aRR 1·44, 95% CI 1·18-1·76). In analysis stratified by genotype, the risk of adverse outcomes was highest in haemoglobin SS (HbSS) pregnancies (n = 80). There was no strong evidence that haemoglobin SC (HbSC) pregnancies (n = 46) were at higher risk of preterm birth, caesarean delivery, or NNU admission. Pre-eclampsia/eclampsia was more frequently observed in HbSC pregnancies. Despite improvements in the care of pregnant women with SCD, the increased risk of adverse perinatal outcomes remains.

Deferiprone vs deferoxamine for transfusional iron overload in SCD and other anemias: a randomized, open-label, noninferiority study

The efficacy of deferiprone was noninferior to deferoxamine for treating transfusional iron overload in patients with SCD or other anemias.

The safety profile of deferiprone in patients with SCD was tolerable and similar to previous reports in patients with thalassemia syndromes.

Many people with sickle cell disease (SCD) or other anemias require chronic blood transfusions, which often causes iron overload that requires chelation therapy. The iron chelator deferiprone is frequently used in individuals with thalassemia syndromes, but data in patients with SCD are limited. This open-label study assessed the efficacy and safety of deferiprone in patients with SCD or other anemias receiving chronic transfusion therapy. A total of 228 patients (mean age: 16.9 [range, 3-59] years; 46.9% female) were randomized to receive either oral deferiprone (n = 152) or subcutaneous deferoxamine (n = 76). The primary endpoint was change from baseline at 12 months in liver iron concentration (LIC), assessed by R2* magnetic resonance imaging (MRI). The least squares mean (standard error) change in LIC was −4.04 (0.48) mg/g dry weight for deferiprone vs −4.45 (0.57) mg/g dry weight for deferoxamine, with noninferiority of deferiprone to deferoxamine demonstrated by analysis of covariance (least squares mean difference 0.40 [0.56]; 96.01% confidence interval, −0.76 to 1.57). Noninferiority of deferiprone was also shown for both cardiac T2* MRI and serum ferritin. Rates of overall adverse events (AEs), treatment-related AEs, serious AEs, and AEs leading to withdrawal did not differ significantly between the groups. AEs related to deferiprone treatment included abdominal pain (17.1% of patients), vomiting (14.5%), pyrexia (9.2%), increased alanine transferase (9.2%) and aspartate transferase levels (9.2%), neutropenia (2.6%), and agranulocytosis (0.7%). The efficacy and safety profiles of deferiprone were acceptable and consistent with those seen in patients with transfusion-dependent thalassemia. This trial study was registered at www://clinicaltrials.gov as #NCT02041299.

The Use of Cost-Effectiveness Analysis in Sickle Cell Disease: A Critical Review of the Literature

Novel interventions for sickle cell disease (SCD) bring hope to patients, yet concern about the associated economic costs exists. Cost-effectiveness analysis (CEA) uses standardized methods, with robust underpinnings in health economics, to estimate the value of these interventions compared with usual care. However, because of the complexity and lifetime trajectory of SCD, CEAs are challenging to conduct. The objectives of this rapid review were to summarize the main characteristics, components, and results of published CEAs of existing interventions for SCD, identify research gaps, and provide directions for future analyses. We identified records through searches of bibliographic databases, from reference lists of relevant review articles, and through consultation with experts. A total of 13 CEAs met our inclusion criteria and were qualitatively synthesized. These evaluated blood transfusions (n = 2), hematopoietic stem cell transplantation (n = 1), pharmaceuticals (n = 2), hypothetical cell or genetic therapy (n = 1), screening programs (n = 4), and interventions for SCD treatment complications (n = 3). A limited number of potential SCD and treatment complications were evaluated. No study adopted a societal perspective in the base case, six studies examined lifetime cost-effectiveness, seven studies employed a Markov or discrete-event simulation model, and eight studies used an outcome metric that captured both quality and length of life. To better compare the value of emerging and current therapies, future CEAs should adopt a societal perspective incorporating both medical and nonmedical costs, comprehensively model SCD complexity using robust health economic simulation models over the patient's entire lifespan, and capture the intervention's effect on both survival and quality of life.

Evaluation of Hepatic Iron Overload Using a Contemporary 0.55 T MRI System

BACKGROUND

MRI T2* and R2* mapping have gained clinical acceptance for noninvasive assessment of iron overload. Lower field MRI may offer increased measurement dynamic range in patients with high iron concentration and may potentially increase MRI accessibility, but it is compromised by lower signal-to-noise ratio that reduces measurement precision.

PURPOSE

To characterize a high-performance 0.55 T MRI system for evaluating patients with liver iron overload.

STUDY TYPE

Prospective.

POPULATION

Forty patients with known or suspected iron overload (sickle cell anemia [n = 5], ß-thalassemia [n = 3], and hereditary spherocytosis [n = 2]) and a liver iron phantom.

FIELD STRENGTH/SEQUENCE

A breath-held multiecho gradient echo sequence at 0.55 T and 1.5 T.

ASSESSMENT

Patients were imaged with T2*/R2* mapping 0.55 T and 1.5 T within 24 hours, and 16 patients returned for follow-up exams within 6-16 months, resulting in 56 paired studies. Liver T2* and R2* measurements and standard deviations were compared between 0.55 T and 1.5 T and used to validate a predictive model between field strengths. The model was then used to classify iron overload at 0.55 T.

STATISTICAL TESTS

Linear regression and Bland-Altman analysis were used for comparisons, and measurement precision was assessed using the coefficient of variation. A P-value < 0.05 was considered statistically significant.

RESULTS

R2* was significantly lower at 0.55 T in our cohort (488 ± 449 s^-1 at 1.5 T vs. 178 ± 155 s^-1 at 0.55 T, n = 56 studies) and in the patients with severe iron overload (937 ± 369 s^-1 at 1.5 T vs. 339 ± 127 s^-1 at 0.55 T, n = 23 studies). The coefficient of variation indicated reduced precision at 0.55 T (3.5 ± 2.2% at 1.5 T vs 6.9 ± 3.9% at 0.55 T). The predictive model accurately predicted 1.5 T R2* from 0.55 T R2* (Bland Altman bias = -6.6 ± 20.5%). Using this model, iron overload at 0.55 T was classified as: severe R2* > 185 s^-1 , moderate 81 s^-1  < R2* < 185 s^-1 , and mild 45 s^-1  < R2* < 91 s^-1 .

DATA CONCLUSION

We demonstrated that 0.55 T provides T2* and R2* maps that can be used for the assessment of liver iron overload in patients.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 2.

Extended phenotyping does not preclude the occurrence of delayed haemolytic transfusion reactions in sickle cell disease

Delayed haemolytic transfusion reaction (DHTR) is a potentially life-threatening complication of red blood cell (RBC) transfusions in sickle cell disease (SCD) and is classically induced by reactivation of previously formed antibodies. Improved antigenic matching has reduced alloimmunization and may reduce DHTR risk. We conducted a retrospective cohort study to investigate the incidence rate of DHTR in SCD patients receiving extended matched units (ABO/RhDCcEe/K/Fy^a /Jk^b /S). Occasional transfusion episodes (OTE) between 2011 and 2020 were reviewed for occurrence of DHTR symptoms using four screening criteria: decreased Hb, increased lactate dehydrogenase (LDH), pain, and dark urine. We included 205 patients who received a cumulative number of 580 transfusion episodes of 1866 RBC units. During follow-up, 10 DHTR events were observed. The incidence rate of DHTR was 13·8/1000 OTEs [95% confidence interval (CI): 7·37-22·2], with a cumulative incidence of 15·2% (95% CI: 8·4-24·0%) after 25 patients having received RBC units. One DHTR event was fatal (10%). Symptoms were misdiagnosed in four DHTR events (40%) as other acute SCD complications. Despite a lower incidence rate compared to most other studies, the incidence rate of DHTR in SCD remains high, in spite of extended matching of donor RBCs. Increased awareness of DHTR is of utmost importance to facilitate early diagnosis and, consequently, improve outcome.

Exploring the Use of Exchange Transfusion in the Surgical Management of Priapism in Sickle Cell Disease: A Population-Based Analysis

INTRODUCTION

Priapism is a urologic emergency that may require surgical intervention in cases refractory to supportive care. Exchange transfusion (ET) has been previously used to manage sickle cell disease (SCD), including in priapism; however, its utilization in the context of surgical intervention has not been well-established.

AIM

To explore the utilization of ET, as well as other patient and hospital-level factors, associated with surgical intervention for SCD-induced priapism METHODS: Using the National Inpatient Sample (2010-2015), males diagnosed with SCD and priapism were stratified by need for surgical intervention. Survey-weighted regression models were used to analyze the association of ET to surgical intervention. Furthermore, negative binomial regression and generalized linear models with logarithmic transformation were used to compare ET vs surgery to length of hospital stay (LOS) and total hospital charges, respectively.

MAIN OUTCOME MEASURES

Predictors of surgical intervention among patients with SCD-related priapism RESULTS: A weighted total of 8,087 hospitalizations were identified, with 1,782 (22%) receiving surgical intervention for priapism, 484 undergoing ET (6.0%), and 149 (1.8%) receiving combined therapy of both ET and surgery. On multivariable regression, pre-existing Elixhauser comorbidities (e.g. ≥2 Elixhauser: OR: 2.20; P < 0.001), other forms of insurance (OR: 2.12; P < 0.001), and ET (OR: 1.99; P = 0.009) had increased odds of undergoing surgical intervention. In contrast, Black race (OR: 0.45; P < 0.001) and other co-existing SCD complications (e.g. infectious complications OR: 0.52; P < 0.001) reduced such odds. Compared to supportive care alone, patients undergoing ET (adjusted IRR: 1.42; 95% CI: 1.10-1.83; P = 0.007) or combined therapy (adjusted IRR: 1.42; 95% CI: 111-1.82; P < 0.001) had a longer LOS vs. surgery alone (adjusted IRR: 0.85; 95% CI: 0.74-0.97; P = 0.017). Patients receiving ET (adjusted Ratio: 2.39; 95% CI: 1.52-3.76; P < 0.001) or combined therapy (adjusted Ratio: 4.42; 95% CI: 1.67-11.71; P = 0.003) had higher ratio of mean hospital charges compared with surgery alone (adjusted Ratio: 1.09; 95% CI: 0.69-1.72; P = 0.710).

CONCLUSIONS

Numerous factors were associated with the need for surgical intervention, including the use of ET. Those receiving ET, as well as those with combined therapy, had a longer LOS and increased total hospital charges. Ha AS, Wallace BK, Miles C, et al. Exploring the Use of Exchange Transfusion in the Surgical Management of Priapism in Sickle Cell Disease: A Population-Based Analysis. J Sex Med 2021;18:1788-1796.

Red blood cell exchange in children with sickle cell disease

The aim of our study was to assess the efficacy of red blood cell exchange (RBCx) using a Spectra Optia® automated apheresis system in children with sickle cell disease (SCD). We used automated RBCx to treat acute and chronic complications in 75 children with SCD who had a median age of 10 years [7-13]. We analyzed 649 RBCx sessions. Peripheral venous access was limited in a number of the children, and thus a femoral double-lumen central venous catheter was required. We recommend heparin locking with 500 units in each lumen of the catheter. To prevent complications, we ensured that all patients had achieved a post-RCE HbS level of < 30%. For chronic transfusion, with a post-RCE Hb level of approximately 10-11 g/dL, a blood exchange volume of ≥ 32 mL/kg, and an interval between each RBCx procedure of ≤ 30 days, the residual HbS level was maintained below 30%. For acute transfusion, a post-exchange Hb level ≥ 10 g/dL (p < 0.001) and a total exchange volume ≥ 35 mL/kg (p = 0.001) were the best way to reduce HbS to < 30%. AUC was 0.84. Our results show that erythrocytapheresis was useful and safe for children with SCD.

Low rates of transfusion-transmitted infection screening in chronically transfused adults with sickle cell disease

BACKGROUND

Adults with sickle cell disease (SCD) on chronic transfusion therapy are exposed to a large volume of blood products, thus increasing their risk of transfusion-associated human immunodeficiency virus (HIV), hepatitis C (HCV), and hepatitis B (HBV).

METHODS

We performed a systematic chart review of chronically transfused SCD subjects at the Johns Hopkins Sickle Cell Center for Adults between October 2014 and September 2019 to determine our Center's adherence to the 2014 National Heart, Lung and Blood Institute (NHLBI) SCD guidelines for annual screening for Transfusion Transmitted infections (TTI) and assessed HBV immunity and HBV vaccination rates.

RESULTS

The study included 85 subjects with a median age of 34 years (23-63); 52% were female. No subject received annual screening; 68 subjects (80%) were screened for HIV, 60 subjects (71%) for HCV and 53 subjects (62%) for HBV infections at least once in the study period. Of those screened, one patient was newly diagnosed with HCV infection, and none with HIV or HBV infection. Among 31 subjects tested for anti-Hepatitis B surface antibody, 16 subjects (52%) tested negative. Nineteen (20%) subjects had HBV vaccination documented.

CONCLUSIONS

Low adherence to the NHLBI TTI screening guidelines, especially for HBV, highlights the resource intensiveness of this patient population. The low rates of anti-Hepatitis B surface antibody positivity highlight the need to confirm vaccination, provide boosters as indicated, and investigate the adults with SCD's immune response to HBV vaccination.

Pediatric Stroke: Overview and Recent Updates

Stroke can occur at any age or stage in life. Although it is commonly thought of as a disease amongst the elderly, it is important to highlight the fact that it also affects infants and children. In both populations, strokes have a high rate of morbidity and mortality. Arguably, it is more detrimental in the pediatric population given the occurrence at a younger age and therefore, a longer duration of disability, potentially over the entire lifespan. The high rate of morbidity and mortality in pediatrics is attributed to significant delays in diagnosis, as well as misdiagnosis. Acute stroke management is time dependent. Patients who receive acute treatment with either intravenous (IV) tissue plasminogen activator (tPA) or mechanical thrombectomy, have improved mortality and functional outcomes. Additionally, the earlier treatment is initiated, the higher the likelihood of preserving penumbra, restoring cerebral blood flow and potentially reversing symptoms, thereby limiting disability. Prompt identification is essential as it leads to improved patient care in such a narrow therapeutic window. It enhances the care received during hospitalization and reduces the risk of early stroke recurrence. Despite limited data and lack of large randomized clinical trials in pediatrics, both IV tPA and mechanical thrombectomy have been successfully used. Bridging the gap of acute stroke management in the pediatric population is an essential part of minimizing adverse outcomes. In this review, we discuss the epidemiology of pediatric stroke, the diverse etiologies, presentation as well as both acute and preventative management.