Impact of chronic transfusion on incidence of pain and acute chest syndrome during the Stroke Prevention Trial (STOP) in sickle-cell anemia

A systematic review of the epidemiology and the public health implications of stroke in Sub-Saharan Africa

BACKGROUND

With approximately 11 million strokes occurring annually worldwide, and over 6.5 million deaths annually, stroke has made its place as one of the major killers in the world. Although developing countries make up more than 4/5 of the global stroke burden, well-grounded information on stroke epidemiology remains lacking there.

AIMS

This systematic review study aimed to provide a synthesis of studies on the incidence and prevalence of stroke among adults in sub-Saharan Africa (SSA), subsequently deduce the associated risk factors and public health implications (mortality rates and economic costs) of the disease on the population of this region.

METHODS

A systematic review of studies carried out in the region and published on PUBMED. Eligibility criteria were established using the PEO (Population/Patient, Exposure, Outcome) format. Research articles investigating either (or all) of the following: ischemic or haemorrhagic stroke, incidence, prevalence, and risk factors of stroke in adults (≥ 18 years old), in at least one region of SSA were included. Exclusion criteria comprised studies involving populations younger than 18 years old, research conducted outside the designated research region, and articles inaccessible in full text. The PRISMA guidelines were used for the search strategy.

RESULTS

Fifty-two studies were included review. Among them, over 11 studies investigated the prevalence of the disease. Some older studies within the continent (Nigeria, 2011) showed a prevalence of 1.3 per 100 while more recent studies (Zambia, 2021) showed a prevalence of 4.3 per 1000. The highest prevalence noted in this region was in Madagascar (2017) with 48.17 per 100, while the lowest was recorded in (Zimbabwe, 2017) with 0.61 per 100. The study in Tanzania showed a crude incidence of 94·5 per 100 000 (76·0-115·0) while the study in Ghana in 2018 showed an incidence of 14.19 events per 1000 person-years [10.77-18.38]. The identified risk factors included hypertension, diabetes, smoking, alcohol consumption, physical inactivity, poor diets (more salt, less vegetables), dyslipidaemia, HIV/AIDS co-infection, heart disease (cardiomyopathies, cardiac arrhythmias), obesity, previous stroke and/or family history of stroke. Over 21 studies investigated the mortality rates due to stroke in SSA, with most of the studies being in West Africa. These studies revealed mortality rates as high as 43.3% in Ghana, and as low as 10.9% in Cameroon. Few studies reported on the economic costs of stroke in the region; two in Benin, two in Nigeria and one in Tanzania.

CONCLUSION

The increasing incidence/prevalence, lifestyle factors and interactions with other diseases, including major communicable diseases, stroke is becoming a pressing public health problem for SSA. Reducing the incidence of stroke in Africa will surely lower mortality, morbidity, disability, and the neurological as well as cognitive aftereffects of stroke, as is clear from the experience of higher-income nations. We recommend a collective intervention involving the governments of nations, international organizations, civil society, and the private sector for greater impact and sustainable outcomes reducing the epidemiology and implications of stroke in SSA.

"Buprenorphine, It Works so Differently": Adults with Sickle Cell Disease Describe Transitioning to Buprenorphine for Treatment of Chronic Pain

A growing body of literature describes the use of buprenorphine for the treatment of chronic pain in people with sickle cell disease. The experiences of people with sickle cell disease who have tried buprenorphine have not yet reported. This qualitative descriptive study was conducted to explore perspectives on buprenorphine for chronic pain in sickle cell disease. We interviewed 13 participants with sickle cell disease who had been prescribed buprenorphine and had a clinic visit between December 1, 2020, and April 2022 in our Sickle Cell Center for Adults. Interviews were recorded, transcribed, and analyzed using thematic analysis. Eleven out of 13 participants were taking buprenorphine at the time of the interview, with a mean treatment duration of 33 months (SD 18, range 7-78 months). Five major themes were identified: 1) dissatisfaction with full agonist opioids; 2) navigating uncertainty with autonomy in deciding to try buprenorphine; 3) functional and relational changes after starting buprenorphine, 4) enduring systemic barriers to pain treatment, and 5) trusting treatment relationships are necessary when approaching patients about buprenorphine. The experience of adulthood living with sickle cell disease before and after starting buprenorphine is qualitatively different with significant improvements in social functioning. PERSPECTIVE: This study examined the experience of adults with sickle cell disease and chronic pain transitioning from full agonist opioids to buprenorphine. It is the first qualitative study of buprenorphine in people with sickle cell disease, contributing to a small but growing literature about buprenorphine and sickle cell disease.

Alloimmunization and hyperhemolysis in sickle cell disease

Alloimmunization against red blood cell antigens and delayed hemolytic transfusion reaction (DHTR) are major barriers to transfusion in sickle cell disease (SCD). In SCD, DHTR is a potentially life-threatening. Blood group polymorphism in SCD patients, who are of African ancestry and frequently exposed to antigens they do not carry; an inflammatory clinical state; and occasional transfusion in acute situations are risk factors for alloimmunization and DHTR. In patients at risk, the transfusion indication must be balanced against the risk of developing DHTR. However, when transfusion is absolutely necessary, protocols combining the prevention of exposure to immunogenic antigens with immunosuppressive treatments must be implemented, and patients should be carefully monitored during posttransfusion follow-up. This close monitoring makes it possible to diagnose hyperhemolysis as soon as possible; to avoid retransfusion, which can exacerbate hemolysis; and to administer specific treatments, such as anticomplement therapy, in severe cases. Finally, in patients with severe disease, hematopoietic stem cell transplantation may be indicated. However, transfusion is also required in this context, and its management is complex because these risks must be taken into account.

Impact of the COVID-19 Pandemic on Iron Overload Assessment by MRI in Patients with Hemoglobinopathies: The E-MIOT Network Experience

BACKGROUND

The E-MIOT (Extension-Myocardial Iron Overload in Thalassemia) project is an Italian Network assuring high-quality quantification of tissue iron overload by magnetic resonance imaging (MRI). We evaluated the impact of the COVID-19 pandemic on E-MIOT services.

METHODS

The activity of the E-MIOT Network MRI centers in the year 2020 was compared with that of 2019. A survey evaluated whether the availability of MRI slots for patients with hemoglobinopathies was reduced and why.

RESULTS

The total number of MRI scans was 656 in 2019 and 350 in 2020, with an overall decline of 46.4% (first MRI: 71.7%, follow-up MRI: 36.9%), a marked decline (86.9%) in the period March-June 2020, and a reduction in the gap between the two years in the period July-September. A new drop (41.4%) was recorded in the period October-December for two centers, due to the general reduction in the total amount of MRIs/day for sanitization procedures. In some centers, patients refused MRI scans for fear of getting COVID. Drops in the MRI services >80% were found for patients coming from a region without an active MRI site.

CONCLUSIONS

The COVID-19 pandemic had a strong negative impact on MRI multi-organ iron quantification, with a worsening in the management of patients with hemoglobinopathies.

CRISPR-Cas9 Editing of the HBG1 and HBG2 Promoters to Treat Sickle Cell Disease

BACKGROUND

Sickle cell disease is caused by a defect in the β-globin subunit of adult hemoglobin. Sickle hemoglobin polymerizes under hypoxic conditions, producing deformed red cells that hemolyze and cause vaso-occlusion that results in progressive organ damage and early death. Elevated fetal hemoglobin levels in red cells protect against complications of sickle cell disease. OTQ923, a clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9-edited CD34+ hematopoietic stem- and progenitor-cell (HSPC) product, has a targeted disruption of the HBG1 and HBG2 (γ-globin) gene promoters that increases fetal hemoglobin expression in red-cell progeny.

METHODS

We performed a tiling CRISPR-Cas9 screen of the HBG1 and HBG2 promoters by electroporating CD34+ cells obtained from healthy donors with Cas9 complexed with one of 72 guide RNAs, and we assessed the fraction of fetal hemoglobin-immunostaining erythroblasts (F cells) in erythroid-differentiated progeny. The gRNA resulting in the highest level of F cells (gRNA-68) was selected for clinical development. We enrolled participants with severe sickle cell disease in a multicenter, phase 1-2 clinical study to assess the safety and adverse-effect profile of OTQ923.

RESULTS

In preclinical experiments, CD34+ HSPCs (obtained from healthy donors and persons with sickle cell disease) edited with CRISPR-Cas9 and gRNA-68 had sustained on-target editing with no off-target mutations and produced high levels of fetal hemoglobin after in vitro differentiation or xenotransplantation into immunodeficient mice. In the study, three participants received autologous OTQ923 after myeloablative conditioning and were followed for 6 to 18 months. At the end of the follow-up period, all the participants had engraftment and stable induction of fetal hemoglobin (fetal hemoglobin as a percentage of total hemoglobin, 19.0 to 26.8%), with fetal hemoglobin broadly distributed in red cells (F cells as a percentage of red cells, 69.7 to 87.8%). Manifestations of sickle cell disease decreased during the follow-up period.

CONCLUSIONS

CRISPR-Cas9 disruption of the HBG1 and HBG2 gene promoters was an effective strategy for induction of fetal hemoglobin. Infusion of autologous OTQ923 into three participants with severe sickle cell disease resulted in sustained induction of red-cell fetal hemoglobin and clinical improvement in disease severity. (Funded by Novartis Pharmaceuticals; ClinicalTrials.gov number, NCT04443907.).

A case report and review of literature on the role of automated red cell exchange in managing sickle cell crisis in India

Red cell exchanges (RCE) help in the treatment of complications of sickle cell anemia (SCA) by reducing the viscosity of blood and improving the oxygen-carrying capacity. We present a case of sickle cell crisis (SCC) managed with automated RCE and also reviewed the literature to assess the utilization and clinical efficiency of this therapy in India. A 19-year-old gentleman diagnosed with SCA presented with acute chest syndrome. Hemoglobin (Hb) was 8.8 g%, hematocrit (HCT) was 24%, and HbS was 90%. As there was worsening of symptoms with conventional management, the patient underwent two procedures of automated RCE. The clinical condition of the patient was improved, HbS was reduced to 16% and HCT was remained at 21% postprocedure. Articles on automated RCE in SCA conducted in India were reviewed and four articles were analyzed based on the search strategy. All the included articles concluded automated RCE as an effective procedure for complications of SCA. Common indication in India was SCA patients undergoing surgery as a prophylactic measure. Automated RCEs are promising as an acute treatment for indicated sickle cell complications. This therapy is underutilized in the Indian scenario, especially in patients with SCC.

The Complex Association of Daily Opioid Dose with Visits for Pain in Sickle Cell Disease: Tolerance or Treatment-Refractory Pain?

INTRODUCTION

Opioids are used for acute and chronic pain in patients with sickle cell disease. How outpatient opioid regimens relate to acute care visits is of interest given the risks of high opioid doses and high hospital utilization. A prior study by our group suggested that outpatient opioid treatment for chronic pain could contribute to a vicious cycle of treatment-refractory acute pain, greater acute care utilization, and escalating opioid doses. The present larger naturalistic observational study was undertaken to determine whether the results were reliable across multiple acute care settings.

METHODS

One year of clinical data on patients (n = 291) followed in the Sickle Cell Center for Adults (August 2018 to July 2019) were extracted, including visits to the emergency department, visits to the infusion center, and inpatient admissions. Outpatient opioid dosage was used to predict acute care treatment in generalized linear models that were controlled for patient, disease, and treatment characteristics.

RESULTS

Outpatient opioid dosage predicted dosage during visits but did not predict visit length or pain relief. Higher outpatient opioid dosage was associated with greater number of visits. However, in post hoc analyses, this relationship was nonlinear, with a clear positive association only for those prescribed the lowest 50% of dosages.

DISCUSSION

Higher outpatient opioid dosage predicted higher dosages during acute care visits to achieve the same pain score improvement, which is more consistent with opioid tolerance than with treatment-refractory pain. The relationship of outpatient opioid dosage with number of acute care visits was more complex, which suggests that opioid consumption at lower levels is driven by intermittent acute pain and opioid consumption at higher levels is driven by chronic pain.

Sickle cell disease in children: an update of the evidence in low- and middle-income settings

Sickle cell disease (SCD), one of the most common monogenetic diseases in the world, is associated with multisystemic complications that begin in childhood. Most of the babies homozygous for the sickle haemoglobin gene are born in sub-Saharan Africa. Over the years, progress has been made with early diagnosis through newborn screening, penicillin prophylaxis, pneumococcal immunisation, transcranial Doppler (TCD) screening, hydroxyurea therapy and chronic blood transfusions with remarkably improved survival and quality of life of children with SCD. However, wide disparities in outcomes exist between high-income countries (HICs) where over 90% survive to adulthood, and low-income and middle-income countries (LMICs) where less than half achieve that milestone. Even in HICs, racial inequities pose barriers to accessing specialised care and receiving treatment for acute pain episodes. Better understanding of SCD pathophysiology is being exploited to develop new disease-modifying drugs and gene therapy approaches to further improve outcomes. Bone marrow transplantation is established as a curative treatment for SCD, but it is largely unavailable in LMICs. To bridge the disparity and inequity gaps, innovative approaches are needed in LMICs. Validated and more affordable, easy-to-use point-of-care tests offer opportunities to link early diagnosis with immunisation programmes and healthcare encounters. Widespread use of hydroxyurea therapy-a relatively affordable and effective disease-modifying drug-in LMICs would help improve survival and quality of life. Integration of SCD treatment into primary care linked to district level/provincial hospitals that are supported with evidence-based guidelines will help extend needed interventions to many more patients living in LMICs.

The Cardiopulmonary Complications of Sickle Cell Disease

Sickle cell disease (SCD) is a genetic hemoglobinopathy associated with extensive morbidity and early mortality. While there have been recent improvements in available disease-modifying therapies for SCD, cardiopulmonary complications remain a major risk factor for death in this population. We provide an overview of current knowledge regarding several of the major acute and chronic cardiopulmonary complications in SCD, including: acute chest syndrome, airway disease, lung function abnormalities, nocturnal hypoxemia and sleep disordered breathing, pulmonary vascular disease, and sickle cell cardiomyopathy.

Implementation of national blood conservation recommendations at an adult sickle cell center

BACKGROUND

Due to the national blood supply crisis caused by the COVID-19 pandemic, the American Society of Hematology proposed guidance to decrease blood utilization for sickle cell patients on chronic transfusion therapy (CTT). Little evidence exists to support the efficacy and safety of these blood conservation strategies.

STUDY DESIGN AND METHODS

Through retrospective analysis, we sought to describe outcomes following implementation of these recommendations in 58 adult sickle cell patients on chronic exchange transfusions. The strategies employed included: relaxing the goal fraction of cells remaining (FCR) to 30%-50%, utilizing depletion exchanges in select patients, and transitioning select patients to monthly simple transfusions. We compared hemoglobin S%, hemoglobin values, and other laboratory parameters, acute care visits, and red blood cell usage during the first year of the COVID-19 pandemic to the year prior using Wilcoxon signed rank test.

RESULTS

Of 53 patients who remained on chronic exchanges during the pandemic, use of depletion exchange increased (15%-23%) and FCR increased (34.9 [SD 4.7] vs. 37.6 [SD 4.5], p < .05). These changes resulted in 854 units conserved without clinically significant changes to pre-exchange laboratory parameters, including hemoglobin S%, or number of acute care presentations. In contrast, five patients who transitioned to predominantly simple transfusions, experienced difficulty maintaining hemoglobin S% less than 30 and worsening anemia.

DISCUSSION

Our data suggest that in a blood shortage crisis, optimizing the exchange procedure itself may be the safest means of conserving blood in a population of adult patients with sickle cell disease.

Barriers and Facilitators to Chronic Red Cell Transfusion Therapy in Pediatric Sickle Cell Anemia

Background: Chronic red cell transfusion (CRCT) therapy is one of a few effective disease-modifying therapies for children with sickle cell anemia (SCA). CRCT is recommended for primary and secondary stroke prevention for at-risk children with SCA and is sometimes used for other disease-related complications. However, CRCT can be resource- and time-intensive for patients/families, providers, and organizations. This study was conducted to provide a comprehensive, multilevel examination of barriers and facilitators to transfusion therapy in children with SCA from health care provider and caregiver perspectives. Methods: A qualitative descriptive approach was used to conduct key informant interviews in a sample of 26 caregivers and 25 providers across the United States. Interviews were analyzed using directed content analysis with the Multilevel Ecological Model of Health as an initial coding framework and the constant comparison method. Results: Ten barrier themes and 10 facilitator themes emerged across all ecological levels. Themes most commonly occurred on the patient and organizational levels. Key barriers themes included Logistical Challenges, Obtaining and Maintaining Venous Access, Alloantibodies/Alloimmunization and Reactions, and Iron Overload and Adherence to Chelation Therapy. Key facilitator themes included Nursing and Non-nursing Staff Support, Positive Child/Family Experiences, Logistical Help and Social Resources, Blood Bank and Access to Blood, and Transfusion-Specific Resources. Discussion: The comprehensive understanding of multilevel barriers and facilitators to transfusion therapy, including the role of nursing, in children with SCA can inform strategies to improve CRCT for patients/families and providers and can also be applied by organizations seeking to implement transfusion services for SCA.

Transcranial doppler as screening method for sickling crises in children with sickle cell anemia: a latin America cohort study

Background

Sickle cell anemia (SCA) is the leading cause of childhood stroke. We aimed to evaluate whether altered cerebral flow velocities, as measured by transcranial Doppler (TCD), are associated with vaso-occlusive complications in addition to stroke in pediatric SCA patients.

Methods

We evaluated 37 children aged between 2 and 16 years with SCA who underwent screening for TCD between January 2012 and October 2018. Genotypic profiles and demographic data were collected, TCD examinations were performed during follow-up, and the presence of sickling crises was compared. Survival analyses were performed using simple frailty models, in which each predictor variable was analyzed separately in relation to the occurrence of a sickling crisis.

Results

The variables related to sickle cell crises in the univariate analysis were peak systolic velocity (PSV) in the middle cerebral artery (MCA), hazard ratio (HR) 1.01 (1.00—1.02) p = 0.04; end-diastolic velocity (EDV) in the MCA, HR 1.02 (1.01—1.04) p = 0.01; time average mean maximum velocity (TAMMV) in the basilar artery (BA), HR 1.02 (1.00—1.04) p = 0.04; hemoglobin, HR 0.49 (0.38—0.65) p < 0.001; hematocrit, HR 0.78 (0.71—0.85) p < 0.001; leukocyte counts, HR 1.1 (1.05—1.15) p < 0.001; platelets counts, HR 0.997 (0.994—0.999) p = 0.02; and reticulocyte numbers, HR 1.14 (1.06—1.23) p < 0.001.

Conclusions

Our results indicate PSV and EDV in the MCA and TAMMV in the BA as markers of risk for the occurrence of sickling crises in SCA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03429-5.

Predictors of Recurrent Acute Chest Syndrome in Pediatric Sickle Cell Disease: A Retrospective Case-Control Study

Acute chest syndrome (ACS) is a common cause of death in sickle cell disease (SCD) patients. Multiple studies investigated the risk factors of developing ACS; however, predictors of recurrent ACS episodes have not been thoroughly investigated. We aim to examine the clinical and laboratory predictors of recurrent ACS in pediatric patients with SCD. A retrospective case-control study included pediatric patients with SCD (˂14 years) admitted with ACS or developed ACS during admission for another indication. Patients were classified into recurrent ACS episodes (≥2 episodes) and a single ACS episode groups. Ninety-one ACS episodes (42 patients) were included, with a mean age at diagnosis of 7.18 ± 3.38 years. Twenty-two (52.4%) patients were male, and twenty-five (59.5%) patients had recurrent ACS. Younger age at first ACS was significantly associated with recurrence (p = 0.003), with an optimal cutoff at 7.5 years (area under the receiver operating characteristic curve [AUROC] = 0.833; p < 0.001). Higher SCD-related hospitalizations were significantly associated with recurrence (p = 0.038). Higher mean values of baseline white blood count (WBC) (p = 0.009), mean corpuscular volume (MCV) (p = 0.011), and reticulocyte (p = 0.036) were significantly associated with recurrence. Contrarily, lower baseline hematocrit values (p = 0.016) were significantly associated with recurrence. The ACS frequencies were significantly lower after hydroxyurea (p = 0.021). The odds of ACS recurrence increased with a positive C-reactive protein (CRP) at admission (p = 0.006). In conclusion, several baseline and admission laboratory data showed significant associations with recurrence. Hydroxyurea therapy demonstrated reduced ACS episodes.

Acute chest syndrome of sickle cell disease: genetics, risk factors, prognosis and management

IntroductionSickle cell disease, one of the world's most prevalent Mendelian disorders, is a chronic hemolytic anemia punctuated by acute vasoocclusive events. Both hemolysis and vasoocclusion lead to irreversible organ damage and failure. Among the many sub-phenotypes of sickle cell disease is the acute chest syndrome (ACS) characterized by combinations of chest pain, cough, dyspnea, fever, abnormal lung exam, leukocytosis, hypoxia, and new radiographic opacities. ACS is a major cause of morbidity and mortality.Area coveredWe briefly review the diagnosis, epidemiology, etiology, and current treatments for ACS and focus on understanding and estimating the risks for developing this complication, how prognosis and outcomes might be improved and the genetic elements that might impact the risk of ACS.Expert opinionThe clinical heterogeneity of ACS has hindered our understanding of risk stratification. Lacking controlled clinical trials most treatment is based on expert opinion. Fetal hemoglobin levels and coexistent α thalassemia affect the incidence of ACS; other genetic associations are tenuous. Transfusions, whose use not innocuous, should be targeted to the severity and likelihood of ACS progression. Stable, non-hypoxic patients with favorable hematologic and radiographic findings usually do not need transfusion; severe progressive ACS is best managed with exchange transfusion.

Indications for transfusion in the management of sickle cell disease

The transfusion of red blood cells (RBCs) is a crucial treatment for sickle cell disease (SCD). While often beneficial, the frequent use of transfusions is associated with numerous complications. Transfusions should be offered with specific guidelines in mind. Here we present updates to the indications for transfusion of RBCs in SCD. We review recent publications and include expert perspectives from hematology and transfusion medicine. For some clinical indications, such as ischemic stroke, the role of transfusion has been well studied and can be applied almost universally. For many other clinical scenarios, the use of transfusion therapy has less conclusive data and therefore must be tailored to individual needs. We highlight the roles of RBC transfusions in preventing or mitigating neurological disease, in reducing perioperative complications, in managing acute chest syndrome, and in optimizing pregnancy outcomes in SCD. We further highlight various transfusion techniques and when each might be considered. Potential complications of transfusion are also briefly discussed.

Red cell transfusion and alloimmunization in sickle cell disease

Red cell transfusion remains a critical component of care for acute and chronic complications of sickle cell disease. Randomized clinical trials demonstrated the benefits of transfusion therapy for prevention of primary and secondary strokes and postoperative acute chest syndrome. Transfusion for splenic sequestration, acute chest syndrome, and acute stroke are guided by expert consensus recommendations. Despite overall improvements in blood inventory safety, adverse effects of transfusion are prevalent among patients with sickle cell disease and include alloimmunization, acute and delayed hemolytic transfusion reactions, and iron overload. Judicious use of red cell transfusions, optimization of red cell antigen matching, and the use of erythrocytapheresis and iron chelation can minimize adverse effects. Early recognition and management of hemolytic transfusion reactions can avert poor clinical outcomes. In this review, we discuss transfusion methods, indications, and complications in sickle cell disease with an emphasis on alloimmunization.

Longitudinal effect of disease-modifying therapy on tricuspid regurgitant velocity in children with sickle cell anemia

Elevated tricuspid regurgitant velocity (TRV) ≥2.5 m/s is a predictor of disease severity in adults and children with sickle cell anemia (SCA), but how disease-modifying therapies (DMTs) affect this biomarker is incompletely understood. We investigated the effect of DMTs on TRV elevation in children. In a prospective single-center study, 204 subjects with HbSS or HbSβ0 thalassemia (mean age, 10.6 years; range, 5-18) had echocardiograms with assessment of TRV, with repeat evaluations after 2 years of observation. One-hundred and twelve participants received DMTs (hydroxyurea, n = 72; monthly erythrocyte transfusions, n = 40), 58 did not receive any DMT, and 34 were begun on hydroxyurea during this observation period. In the entire cohort, an increase in hemoglobin of 1.0 g/dL was associated with a 0.03-m/s decrease in TRV (P = .024), and a decrease in absolute reticulocyte count of 1.0 × 106/mL was associated with a 0.34-m/s decrease in TRV (P = .034). Compared with baseline, hydroxyurea exposure (continuous or newly started) was associated with an average 5% decline in mean TRV at the 2-year evaluation. Among participants newly started on hydroxyurea (mean treatment duration 1.2 ± 0.6 years), an increase in hemoglobin of 1.0 g/dL was associated with a 0.06-m/s decrease in TRV (P = .05). We conclude that hydroxyurea therapy may mitigate TRV elevation in children with SCA, possibly as a result of a reduction in hemolysis and improvement in anemia.

American Society of Hematology 2020 guidelines for sickle cell disease: management of acute and chronic pain

BACKGROUND

The management of acute and chronic pain for individuals living with sickle cell disease (SCD) is a clinical challenge. This reflects the paucity of clinical SCD pain research and limited understanding of the complex biological differences between acute and chronic pain. These issues collectively create barriers to effective, targeted interventions. Optimal pain management requires interdisciplinary care.

OBJECTIVE

These evidence-based guidelines developed by the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in pain management decisions for children and adults with SCD.

METHODS

ASH formed a multidisciplinary panel, including 2 patient representatives, that was thoroughly vetted to minimize bias from conflicts of interest. The Mayo Evidence-Based Practice Research Program supported the guideline development process, including updating or performing systematic reviews. Clinical questions and outcomes were prioritized according to importance for clinicians and patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used, including GRADE evidence-to-decision frameworks, to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel reached consensus on 18 recommendations specific to acute and chronic pain. The recommendations reflect a broad pain management approach, encompassing pharmacological and nonpharmacological interventions and analgesic delivery.

CONCLUSIONS

Because of low-certainty evidence and closely balanced benefits and harms, most recommendations are conditional. Patient preferences should drive clinical decisions. Policymaking, including that by payers, will require substantial debate and input from stakeholders. Randomized controlled trials and comparative-effectiveness studies are needed for chronic opioid therapy, nonopioid therapies, and nonpharmacological interventions.

Empirically Derived Profiles of Health-Related Quality of Life in Youth and Young Adults with Sickle Cell Disease

OBJECTIVE

Determining how the health-related quality of life (HRQOL) is impacted by living with Sickle Cell Disease (SCD) can inform psychosocial interventions. The purpose of the present study is to determine if demographic and treatment variables predict membership into empirically derived subgroups of HRQOL among youth and young adults with SCD.

METHODS

Three hundred and seven youth and young adults with SCD (mean 17.63 years ± 3.74 years, 50.5% female) completed the Pediatric Quality of Life InventoryTM Sickle Cell Disease Module. Latent profile analysis examined subgroups/classes of HRQOL and relationships with demographic and treatment variables.

RESULTS

Three distinct classes emerged: High HRQOL (34% of the sample), Moderate HRQOL (44% of the sample), and Low HRQOL (22% of the sample). Being female was associated with increased odds of being in the moderate or low groups. Living with more severe SCD (genotypes HbSS and HbSβ0 thalassemia) was associated with increased odds of being in the Low HRQOL group. Treatment with chronic red blood cell transfusion therapy was associated with increased odds of being in the High HRQOL group. Older age predicted a small increase in the odds of being in the Low versus High HRQOL group.

CONCLUSIONS

The present study adds to the literature on HRQOL in SCD by exploring person-centered, empirically derived groups of HRQOL. Identification of demographic and treatment factors that predict membership into those groups within a large sample assists in tailoring needed psychosocial interventions for youth with SCD.

Patterns of healthcare utilization among patients with sickle cell disease hospitalized with pain crises

Background

Vaso‐occlusive crises (VOC) are the hallmark of sickle cell disease (SCD). Adults experiencing VOC often have high rates of unexpected healthcare utilization. We characterized prior and future healthcare utilization among adults hospitalized with VOC at an urban, academic medical center.

Methods

We identified 449 VOC hospitalizations among 63 patients from 2013 to 2016. Patients were categorized based on receiving established care at the medical center and prior utilization: (a) not established (n = 21); (b) newly established (n = 10); (c) established with low utilization in past 12 months (<4 VOC hospitalizations) (n = 22); and (d) established with high utilization in past 12 months (≥4 VOC hospitalizations) (n = 10). Patient and hospitalization characteristics and future utilization were compared across categories.

Results

Median age was 26 years (Q1 = 22, Q3 = 29) and 55.6% were female. Established patients with high prior utilization tended to have higher median pain scores at admission (10, P = .08). Thirty‐day readmissions were highest in established patients with high prior utilization (P = .06), but 30‐day clinic visits were highest in established patients with low prior utilization (P = .08). Adjusted linear regression found that newly established patients (β = −4.6, P < .01) and established patients with low prior utilization (β = −5.6, P < .01) had fewer VOC hospitalizations in the ensuing 12 months than established patients with high prior utilization.

Conclusion

Among patients with SCD hospitalized for VOC, there was heterogeneity in healthcare utilization, with persistence in utilization over time for some patients. Efforts are needed to shift care from the acute setting to the outpatient clinic, which may lead to improved outcomes.

Prognostic Value of Hyponatremia During Acute Painful Episodes in Sickle Cell Disease

BACKGROUND

Low plasma sodium concentration has been recognized as a prognostic factor in several disorders but never evaluated in sickle cell disease. The present study evaluates its value at admission to predict a complication in adult patients with sickle cell disease hospitalized for an initially uncomplicated acute painful episode.

METHODS

The primary outcome of this retrospective study, performed between 2010 and 2015 in a French referral center for sickle cell disease, was a composite criterion including acute chest syndrome, intensive care unit transfer, red blood cell transfusion or inpatient death. Analyses were adjusted for age, sex, hemoglobin genotype and concentration, lactate dehydrogenase (LDH) concentration, and white blood cell count.

RESULTS

We included 1218 stays (406 patients). No inpatient death occurred during the study period. Hyponatremia (plasma sodium ≤135 mmol/L) at admission in the center was associated with the primary outcome (adjusted odds ratio [OR] 1.95, 95% confidence interval [CI] 1.3-2.91, P = 0.001), with acute chest syndrome (OR 1.95 [95% CI 1.2-3.17, P = 0.008]), and red blood cell transfusion (OR 2.71 [95% CI 1.58-4.65, P <0.001]) but not significantly with intensive care unit transfer (OR 1.83 [95% CI 0.94-3.79, P = 0.074]). Adjusted mean length of stay was longer by 1.1 days (95% CI 0.5-1.6, P <0.001) in patients with hyponatremia at admission.

CONCLUSIONS

Hyponatremia at admission in the medical department for an acute painful episode is a strong and independent prognostic factor of unfavorable outcome and, notably, acute chest syndrome. It could help targeting patients who may benefit from closer monitoring.

Automated exchange compared to manual and simple blood transfusion attenuates rise in ferritin level after 1 year of regular blood transfusion therapy in chronically transfused children with sickle cell disease

BACKGROUND

Optimal strategies for regular blood transfusion therapy are not well defined in sickle cell disease (SCD). This analysis tested the hypothesis that in the first of year of regular transfusions, when chelation therapy use is minimal, automated exchange transfusion would be the superior method for attenuating the rise in ferritin levels compared to simple and manual exchange transfusions.

STUDY DESIGN AND METHODS

The Silent Cerebral Infarct Multi-Center Clinical Trial randomly allocated children with SCD and silent cerebral infarcts to receive standard care or regular transfusions with a target pre-transfusion HbS concentration ≤ 30% and minimum hemoglobin level > 9.0 g/dL. Participants with at least nine transfusions and sufficient ferritin testing in the first year of the trial were included in a planned secondary analysis. Ferritin levels by the end of the first study year were compared between participants receiving automatic exchange transfusion, manual exchange transfusion, and simple transfusion.

RESULTS

A total of 83 participants were analyzed. During the first year of the study, 75.9% of the participants had >80% of transfusions via one transfusion method. At baseline no significant differences in ferritin levels were observed in the three transfusion groups (p = 0.1). After 1 year of transfusions the median (interquartile range) ferritin levels in the simple transfusion (n = 40), manual exchange transfusion (n = 34) and automatic exchange transfusion (n = 9) groups were 1800 ng/mL (1426-2204 ng/mL), 1530 ng/mL (1205-1805 ng/mL), and 355 ng/mL (179-579 ng/mL), respectively (p < 0.001).

CONCLUSION

Automated exchange transfusion, when compared to other transfusion methods, is the optimal transfusion strategy for attenuating increase in ferritin levels in children with SCD.

Transfusion support: Considerations in pediatric populations

Over 400,000 units of blood and blood products are transfused to pediatric patients annually, yet only sparse high-quality data exist to guide the preparation and administration of blood products in this population. The direct application of data from studies in adult patients should be undertaken with caution, as there are dissimilarities in the pathology and physiology between adult and pediatric patients. We provide an overview of available evidence in the field of pediatric transfusion medicine, summarizing indications for blood product transfusion, thresholds for transfusion and indications for blood product modifications.

Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease

BACKGROUND

Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation. This is an update of a Cochrane Review first published in 2002, and last updated in 2017.

OBJECTIVES

To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts).

SEARCH METHODS

We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 8 October 2019. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 19 September 2019.

SELECTION CRITERIA

Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial eligibility and the risk of bias and extracted data.

MAIN RESULTS

We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease. Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion. Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents). The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusions Long-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence. Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence. We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants) We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence. Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks). The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelation Neither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants) Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants) Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence.

AUTHORS' CONCLUSIONS

There is no evidence for managing adults, or children who do not have HbSS sickle cell disease. In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications. In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration. In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events. All other evidence in this review is of very low quality.

Red cell exchange for patients with sickle cell disease: an international survey of current practices

INTRODUCTION

Red cell exchange (RCE) therapy is increasingly used to treat patients with acute or chronic manifestations of sickle cell disease (SCD). However, little is known regarding the most safe and effective practice parameters associated with this particular therapy.

METHODS

A SCD subcommittee of members of the American Society for Apheresis (ASFA) developed a 122-question survey and administered it via email to other ASFA members. The survey inquired about clinical indications for treatment, practice patterns, and transfusion policies for RCE when used for patients with SCD.

RESULTS

Ninety-nine distinct institutions completed the survey. Twenty-one (21%) were from outside of the US. Twenty-two (22%) provided chronic transfusion therapy to >10 patients, and both adult (25%) and pediatric-focused services (20%) were represented. Common acute indications for RCE included acute chest syndrome, acute ischemic stroke, and pre-surgical prophylaxis. Common chronic indications included primary stroke prophylaxis, secondary stroke prophylaxis, and recurrent acute chest syndrome. Respondents most commonly set a post-RCE treatment target of 30% for the hematocrit and hemoglobin S levels, regardless of the therapeutic indication. Units for RCE were phenotypically matched in 95% of cases. About 40% of respondents reported using isovolemic hemodilution.

CONCLUSIONS

This survey solicited the current practice variations in RCE from a diverse range of practice sites. Many sites reported similar practice patterns and challenges but some variations emerged. To our knowledge, this survey represents the largest and most in-depth investigation of the use of RCE for patients with SCD, and could inform future studies in the field.

Association between Vaso-occlusive Crises and Opioid Prescriptions among Patients with Sickle Cell Disease: A Retrospective Claims-based Study

BACKGROUND/OBJECTIVES

Among sickle cell disease (SCD) patients, vaso-occlusive crises (VOCs) are recurrent and unpredictable attacks of acute pain. These pain crises are often treated with analgesics, including opioids, which have been associated with misuse and overdose. The aim of this study was to examine the association between VOC events and opioid use and assess the association between opioid prescriptions and health care resource utilization among SCD patients.

METHODS

This was a retrospective cohort study using Texas Medicaid medical and prescription claims between September 2011 and August 2016. The index date was the first SCD diagnosis. Patients (2-63 years) with at least one inpatient or two outpatient SCD diagnoses, who were continuously enrolled during 12 months postindex, were included in the study. The primary outcome was number of opioid prescriptions, while the independent variable was number of VOC events. Covariates included age, gender, nonopioid medication use, nonstudy SCD-related medication (penicillin and folic acid) use, evidence of blood transfusions, number of SCD-related complications, number of SCD-related comorbid conditions, and Charlson Comorbidity Index score. Negative binomial regression analysis was used to address study objectives.

RESULTS

Of 3368 included patients, 1978 (58.7%) had at least one opioid prescription with a mean of 4.2 (SD=7.2). Overall, 2071 (61.5%) had at least one VOC event with an average of 2.9 (SD=4.4). The results from the negative binomial regression showed that for every increase in VOC events, the number of opioid prescriptions increased by 9.5% (Incidence rate ratio=1.095, 95% CI: 1.078-1.111; P ≤ 0.0001). Other significant covariates associated with higher opioid use included age (13 and older compared to 2-12) and increase in the number of nonopioid pain medications, nonstudy SCD-related medications, and SCD-related complications.

CONCLUSIONS

The majority of SCD patients had at least one VOC event and were prescribed opioids during the 12-month study period. We found that each VOC event was associated with a 9.5% increase in the use of opioids. SCD guidelines recommend opioids for the treatment of VOC-related pain. Payers and providers should be aware of opioid use in this population, consider appropriate VOC prevention measures, and provide SCD patients with access to appropriate pain management.

Blood utilization and characteristics of patients treated with chronic transfusion therapy in a large cohort of Brazilian patients with sickle cell disease

BACKGROUND

Red blood cell (RBC) transfusions are used in sickle cell disease (SCD) to treat acute complications or as chronic transfusion therapy (CTT) to prevent severe manifestations. The objectives of this study were to describe blood utilization and adverse events (AEs) associated with RBCs in the Brazilian SCD population and compare characteristics of patients treated or not with CTT.

STUDY DESIGN AND METHODS

A SCD cohort was established at six Brazilian centers. Medical and blood bank records were abstracted for clinical and transfusion history. Two controls not treated with CTT matched on center, SCD genotype, sex, and age were selected for each CTT case within the cohort to compare characteristics between the two groups.

RESULTS

Most of the 2794-member cohort had received a transfusion (75.0% of children and 89.2% of adults) with 29.2% of patients receiving transfusion in the prior year. There were 170 (10.6%) children and 115 (9.2%) adults treated with CTT. Children not treated with CTT were more likely to have pain and acute chest hospitalizations in the prior year (25.3% vs. 11.9%, p = 0.0003; and 22.0% vs. 10.7%, p = 0.002, respectively). Both iron overload and alloimmunization were more common in CTT cases compared to controls (65.6% vs. 17.0% and 36.2% vs. 15.9%, respectively). A higher proportion of adults treated with CTT demonstrated oxygen saturation of greater than 95% compared to controls not treated (51.1% vs. 39.2%), while there was no difference in oxygenation between children treated or not. Of 4501 transfusion episodes, 28 (0.62%) AEs were reported. There was no difference in AEs associated with transfusions for acute indications versus CTT.

CONCLUSION

Red blood cell transfusion was common in Brazilian SCD patients, with utilization driven by CTT. Transfusion reactions were not common; however, alloimmunization and iron overload were frequent among those on CTT, highlighting the need for novel clinical strategies to mitigate these risks.

Evaluation of Ocular Complications by Using Optical Coherence Tomography in Children With Sickle Cell Disease Eye Findings in Children With Sickle Cell Disease

OBJECTIVE

The aim of this study was to compare optical coherence tomography (OCT) findings in pediatric patients with sickle cell disease (SCD) and healthy individuals and to investigate associations between these data and the patients' systemic findings.

MATERIALS AND METHODS

The study included 108 eyes of 54 patients with SCD with no visual symptoms and a control group consisting of 110 eyes of 55 healthy subjects with no systemic or ocular pathology. After best-corrected visual acuity assessment, the study participants underwent a complete ophthalmologic examination including intraocular pressure. After examination and pupil dilation induced with 1% tropicamide, 9×9 mm macular sections were obtained with spectral-domain OCT. The macular sections were evaluated according to Early Treatment Diabetic Retinopathy Study (ETDRS) map and internal and external retinal thicknesses were measured using the software included in the OCT device.

RESULTS

The patient group showed significantly more foveal flattening, temporal thinning, and vascular tortuosity than the control group (P<0.0001 for all). Foveal width was significantly greater in the patient group (1592.39±175.56 µm) compared with the control group (1391.01±175.56 µm) (P<0.0001), whereas foveal depth was significantly lower in the patient group (121.15±26.83 µm) than in the control group (146.1±12.25 µm) (P<0.0001). The mean total retinal thickness was 253.53±22.31 µm in the patient group and 261.03±18.48 µm in the control group (P=0.007). Similarly, central retinal thickness was significantly lower in the patient group (219.35±10.53 µm) compared with the control group (235.32±12.51 µm) (P<0.0001).

DISCUSSION

Our study shows that pediatric patients with SCD may have subclinical retinal involvement and that temporal thinning, in particular, is an important OCT finding. This strongly suggests that OCT imaging would be a beneficial addition to routine ophthalmologic examination in the diagnosis and follow-up of this patient group.

Blood transfusions for treating acute chest syndrome in people with sickle cell disease

BACKGROUND

Sickle cell disease is an inherited autosomal recessive blood condition and is one of the most prevalent genetic blood diseases worldwide. Acute chest syndrome is a frequent complication of sickle cell disease, as well as a major cause of morbidity and the greatest single cause of mortality in children with sickle cell disease. Standard treatment may include intravenous hydration, oxygen as treatment for hypoxia, antibiotics to treat the infectious cause and blood transfusions may be given. This is an update of a Cochrane Review first published in 2010 and updated in 2016.

OBJECTIVES

To assess the effectiveness of blood transfusions, simple and exchange, for treating acute chest syndrome by comparing improvement in symptoms and clinical outcomes against standard care.

SEARCH METHODS

We searched The Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register, which comprises references identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings. Date of the most recent search: 30 May 2019.

SELECTION CRITERIA

Randomised controlled trials and quasi-randomised controlled trials comparing either simple or exchange transfusion versus standard care (no transfusion) in people with sickle cell disease suffering from acute chest syndrome.

DATA COLLECTION AND ANALYSIS

Both authors independently selected trials and assessed the risk of bias, no data could be extracted.

MAIN RESULTS

One trial was eligible for inclusion in the review. While in the multicentre trial 237 people were enrolled (169 SCC, 42 SC, 15 Sβ⁰-thalassaemia, 11Sβ⁺-thalassaemia); the majority were recruited to an observational arm and only ten participants met the inclusion criteria for randomisation. Of these, four were randomised to the transfusion arm and received a single transfusion of 7 to 13 mL/kg packed red blood cells, and six were randomised to standard care. None of the four participants who received packed red blood cells developed acute chest syndrome, while 33% (two participants) developed acute chest syndrome in standard care arm. No data for any pre-defined outcomes were available.

AUTHORS' CONCLUSIONS

We found only one very small randomised controlled trial; this is not enough to make any reliable conclusion to support the use of blood transfusion. Whilst there appears to be some indication that chronic blood transfusion may play a roll in reducing the incidence of acute chest syndrome in people with sickle cell disease and albeit offering transfusions may be a widely accepted clinical practice, there is currently no reliable evidence to support or refute the perceived benefits of these as treatment options; very limited information about any of the potential harms associated with these interventions or indeed guidance that can be used to aid clinical decision making. Clinicians should therefore base any treatment decisions on a combination of; their clinical experience, individual circumstances and the unique characteristics and preferences of adequately informed people with sickle cell disease who are suffering with acute chest syndrome. This review highlights the need of further high quality research to provide reliable evidence for the effectiveness of these interventions for the relief of the symptoms of acute chest syndrome in people with sickle cell disease.

Guidelines on the Use of Therapeutic Apheresis in Clinical Practice - Evidence-Based Approach from the Writing Committee of the American Society for Apheresis: The Eighth Special Issue

The American Society for Apheresis (ASFA) Journal of Clinical Apheresis (JCA) Special Issue Writing Committee is charged with reviewing, updating and categorizing indications for the evidence-based use of therapeutic apheresis (TA) in human disease. Since the 2007 JCA Special Issue (Fourth Edition), the committee has incorporated systematic review and evidence-based approaches in the grading and categorization of apheresis indications. This Eighth Edition of the JCA Special Issue continues to maintain this methodology and rigor in order to make recommendations on the use of apheresis in a wide variety of diseases/conditions. The JCA Eighth Edition, like its predecessor, continues to apply the category and grading system definitions in fact sheets. The general layout and concept of a fact sheet that was introduced in the Fourth Edition, has largely been maintained in this edition. Each fact sheet succinctly summarizes the evidence for the use of TA in a specific disease entity or medical condition. The Eighth Edition comprises 84 fact sheets for relevant diseases and medical conditions, with 157 graded and categorized indications and/or TA modalities. The Eighth Edition of the JCA Special Issue seeks to continue to serve as a key resource that guides the utilization of TA in the treatment of human disease.

Chronic transfusion therapy effectiveness as primary stroke prophylaxis in sickle cell disease patients

Introduction

About 10% of sickle cell anemia patients will have ischemic stroke. Adams showed stroke incidence reduction in children receiving monthly erythrocyte transfusions by reducing transcranial Doppler (TCD) velocities. Since then, chronic transfusion is recommended as primary stroke prophylaxis. This study aims to assess the effectiveness of chronic transfusions as stroke prophylaxis.

Method

Retrospective study, reviewing medical records from 15 sickle cell anemia patients undergoing chronic transfusion. Data collected were age, sex, adverse reactions, stroke, hemoglobin, reticulocytes, ferritin, HbS and TCD values (baseline, after 12 and 24 months of treatment).

Results

The mean age was 118.67 ± 41.40 months; six patients experienced allergic reactions. No stroke was recorded. One patient had alloimmunization. There was a decrease in the HbS rate and an increase in hemoglobin values in the first 12 months. Values were maintained after 24 months, but with no improvement of data. Before treatment, the mean HbS rate was 75.18%±11.69; after 12 months, 41.63 ± 14.99 and after 24 months, 43.78 ± 10.6. Thirteen patients initiated chelation after 12 months from the beginning of chronic transfusions and ferritin decline after 24 months. Pre-transfusional TCD velocities were 204.28 ± 9.41 cm/s (right) and 198.85 ± 33.37 cm/s (left). After a 12-month treatment, these values were 158.5 ± 28.89 cm/s and 157.62 ± 34.43 cm/s, respectively, and this reduction was statistically significant (p = 0.002 right and p = 0.02 left). After 24 months, these values were 149.63 ± 26.95 cm/s (right) and 143.7 ± 32.27 cm/s (left).

Conclusion

Significant reduction of TCD velocity occurred after treatment with chronic transfusion in sickle cell anemia patients, leading to a normal or conditional test and reducing stroke risk in all but one patient.

The controversial role of red cell transfusions for sickle cell pain

PURPOSE OF REVIEW

Red cell transfusions are one of the most common and important therapies used for patients with sickle cell disease (SCD). For prevention of strokes, there is abundant evidence that transfusions are efficacious, whereas for other indications, such as prevention of pain, there are less data. Nonetheless, with few therapeutic options, the use of transfusion for prevention of acute pain has increased in children and adults with SCD without a clear understanding of its benefits.

RECENT FINDINGS

Although it makes conceptual sense that red cell transfusions would prevent pain that arises from vaso-occlusion, we now know that the mechanism of pain is more complex than vaso-occlusion alone. Recent taxonomies recognize a chronic pain syndrome that is both common in adults with SCD and affects the presentation of acute pain. It is not known if acute pain on the background of chronic pain responds differently to sickle cell therapies, such as hydroxyurea and blood transfusion.

SUMMARY

In this review, we will examine the studies that have investigated whether red cell transfusions are efficacious for preventing pain. In the absence of high-quality data that specifically addresses this question, we will outline our approach, which might soon change with new drugs and curative therapies on the horizon.

Chronic pain persists in adults with sickle cell disease despite regular red cell transfusions

BACKGROUND

Pain affects over 50% of adults with sickle cell disease (SCD), and this pain is largely managed outside of the hospital. While chronic transfusion therapy is used to decrease the rate of acute pain events in patients with SCD, less is known about its impact on the day-to-day experience of pain. To address this knowledge gap, we provided pain diaries to patients with SCD receiving chronic transfusion.

PATIENTS AND METHODS

A convenience sample of chronically-transfused adults with SCD successfully completed a diary over the course of at least 2 transfusion events. Patients receiving simple transfusions and red cell exchanges were included. Pain was rated on a scale of 0 to 10 each day, and patient laboratory values, co-morbidities, and hospital utilization were also obtained using the electronic medical record. The mean pain scores pre- and post-transfusion were evaluated using both a random effects-expectation maximization regression tree analysis and a generalized linear mixed regression model.

RESULTS

Ten subjects (63%) in this cohort were defined as having chronic pain, while the remaining four (27%) subjects had episodic pain. Despite chronic transfusion and a suppressed HbS% (22.5% (16.5-25.9)), 10 patients (63%) continued to report nearly daily pain, and on almost 70% of diary days, the pain was significant (≥5/10). When the relationship between HbS% and reported pain intensity was examined, no association was found.

DISCUSSION

These results suggest that, even with regular transfusions and a low HbS%, daily pain persists in many adults with SCD.

Health-related Quality of Life in Children With Sickle Cell Disease Undergoing Chronic Red Cell Transfusion Therapy

Chronic red cell transfusion (CRCT) therapy is one of few disease-modifying treatments for sickle cell disease (SCD). This study evaluated health-related quality of life (HRQL) in children receiving CRCT relative to 2 comparison groups: children with similar, severe SCD and children with milder disease risk defined by SCD genotype. For this study, 67 children with SCD between the ages of 8 and 18 completed the self-report Pediatric Quality of Life Sickle Cell Disease module (PedsQL SCD) as part of a pilot clinical program during routine hematologic visits. A medical chart review was also performed. Linear regression suggested that children in the CRCT group had significantly higher self-reported HRQL ratings for domains related to pain, F2,64=4.07 (P=0.022) and pain-related functioning, F2,64=4.32 (P=0.017), compared with children with similar and milder disease risk. Exploratory analyses implied that children in the CRCT group also had fewer worries about SCD-related complications, F3,63=9.68 (P<0.001). These patient-perceived benefits of CRCT may have important implications for treatment decisions and for providing ancillary support for children with SCD and their families.

Recommendations for the use of red blood cell exchange in sickle cell disease

Sickle cell disease (SCD) is a genetic disorder characterised by a single mutation of the beta globin gene, causing the production of an abnormal haemoglobin called sickle haemoglobin (HbS). In its deoxygenated form, HbS polymerises, causing major rheological disorders, which presents clinically as periodic vaso-occlusive crises, chronic haemolysis and chronic vascular dysfunction. Patients often resort to a background treatment, and transfusion remains the cornerstone in the management of the disease, significantly reducing morbidity and mortality. The aim of red blood cell exchange (RBCX) is to improve tissue oxygenation by increasing haemoglobin levels while lowering HbS levels. RBCX can be performed by manual or automated exchange, and each technique has its own set of advantages and disadvantages. This article will outline the transfusion indications for the main complications of SCD, as well as the most appropriate strategy to use.

Clinical and Ophthalmic Factors Associated With the Severity of Sickle Cell Retinopathy

PURPOSE

To identify associations between severity of sickle cell retinopathy (SCR) and other clinical, laboratory, or treatment factors relevant to sickle cell disease (SCD).

DESIGN

Retrospective cohort study.

METHODS

We investigated clinical, laboratory, and demographic associations with the severity of SCR in 296 patients seen at both our SCD specialty clinic and our retina clinic. Multivariate multinomial logistic regression was used to estimate the association between each clinical variable and severity of SCR.

RESULTS

Multivariate analysis showed that in patients with sickle cell anemia (SCA) genotypes, older age (95% confidence interval [CI], 1.04-1.15; P < .001) and male sex (95% CI, 0.13-0.87; P = .02) were associated with proliferative sickle cell retinopathy (PSR). In patients with genotypic variants, visual symptoms (95% CI, 1.36-21.62; P = .02) were associated with PSR. Laser photocoagulation and vitrectomy surgery, the standard interventions for PSR, were associated with older age (95% CI, 1.05-1.13; P < .001), visual symptoms (95% CI, 1.48-7.40; P = .004), higher hemoglobin level (95% CI, 1.14-1.65; P = .001), and no chronic transfusion (95% CI, 0.16-1.09; P = .08) across the whole cohort.

CONCLUSIONS

These findings may inform clinicians of the symptoms, systemic findings, and disease-modifying therapies most frequently associated with SCR in SCD patients. Visual symptoms such as blurred vision or floaters were associated with progression of SCR and may be criteria for referral for retinal examination. Chronic transfusion therapy may be protective against the need for retinal laser photocoagulation or vitrectomy. Prospective studies are necessary to further explore risk factors for SCR and to identify which individuals with SCD are at risk for incident or progression of retinopathy.

Red blood cell transfusion therapy for sickle cell patients with frequent painful events

BACKGROUND

Recurrent pain events or chronic pain are among the most common complications of sickle cell disease. Despite attempts to maximize adherence to and dosing of hydroxyurea, some patients continue to suffer from pain. Our institution developed a program to initiate chronic red blood cell transfusions for one year in patients clinically deemed to have high healthcare utilization from sickle cell pain, despite being prescribed hydroxyurea.

PROCEDURE

An institutional review board approved retrospective study to evaluate the health outcomes associated with a one-year red blood cell transfusion protocol in sickle cell patients experiencing recurrent pain events as compared with the health outcomes for these patients in the one year prior to receiving transfusion therapy. We performed a matched-pair analysis using a Wilcoxon signed rank to determine the impact of transfusion therapy on clinic visits, emergency department visits, hospital admissions, hospitalization days, and opioid prescriptions filled.

RESULTS

One year of transfusion therapy significantly reduced the number of total emergency department visits for pain (6 vs 2.5 pain visits/year, P = 0.005), mean hospitalizations for pain (3.4 vs 0.9 pain admissions/year), and mean hospital days per year for pain crisis (23.5 vs 4.5, P = 0.0001), as compared with the one year prior to transfusion therapy. We identified no significant difference in opioid prescriptions filled during the year of transfusion therapy.

CONCLUSION

Patients with frequent pain episodes may benefit from one year of transfusion therapy.

Impact of early analgesia on hospitalization outcomes for sickle cell pain crisis

BACKGROUND

Painful events are the leading cause of hospitalizations for patients with sickle cell disease. Individualized pain plans targeting patient-specific maximum opioid dosing may shorten hospitalization length and are recommended by national guidelines. Prior to implementing individualized sickle cell pain plans, we tested the hypothesis that a shorter time to achieve a maximum opioid dose would improve hospitalization outcomes.

PROCEDURE

Two-year IRB-approved, retrospective study of pediatric patients admitted for vaso-occlusive crisis (VOC). We recorded the emergency department admission time, order entry time for the maximum opioid dose during the hospitalization, and time of discharge orders.  We categorized patients as infrequent if they required <3 admissions for VOC over two years and patients as frequent if they required ≥3 admissions for VOC over two years. To account for multiple admissions, generalized linear modeling was performed.

RESULTS

We identified 236 admissions for acute pain observed in 108 patients. Achieving an earlier maximum opioid dose was significantly associated with shorter length of hospitalization for frequent and infrequent pain patients (both P ≤ 0.0001). As total hospitalization length can be impacted by the time a maximum opioid order was placed, we also analyzed hospitalization length after the maximum opioid order was placed. Frequent pain patients who achieved earlier analgesia had a significantly shorter hospitalization from the time the maximum opioid order was placed (P = 0.03) while no association was found for infrequent pain patients (P = 0.84).

CONCLUSIONS

Early achievement of maximum analgesia improved hospitalization outcomes and warrant further investigation in prospective studies of individualized pain plans.

Indwelling ports for prophylactic RBC exchanges in sickle cell patients: Comparison of bard and vortex ports

INTRODUCTION

Red blood cell exchange (RCE) procedures are commonly used for stroke prevention in sickle cell disease (SCD) patients. We compared two different dual lumen ports used for RCE because differences between the port and catheter design may lead to functional variance.

METHODS

We reviewed the RCE parameters of SCD patients following implantable port placement encountered at a single institution. Five Vortex and four Bard ports were used and compared. Patients were followed for 1-24 exchange procedures over 3-26 months performed between 2013 and 2015.

RESULTS

Nine patients underwent 124 RCE procedures with no failures. A total of 74 exchanges used Vortex ports with a mean flow rate of 45.2 mL/min while 50 exchanges used Bard ports with a mean flow rate of 42.1 mL/min which was a significant difference (P = .002). A total of 85 exchanges with tPA administration preprocedure had a mean flow rate of 43.8 mL/min while 39 exchanges without had a mean flow rate of 45.4 mL/min which was not a significant difference (P = .19).

CONCLUSION

Both the Bard and Vortex ports functioned well during our study period with no treatment failures, no significant complications requiring removal or replacement, and adequate mean flow rates. While the difference in mean flow rates was statistically significant between Vortex and Bard ports, there may not be a practical difference in performance. There also does not appear to be a significant benefit in flow rates with preprocedure tPA. We conclude that both ports may be a satisfactory choice for vascular access in SCD patients expected to undergo regularly scheduled RCE.

Hematopoietic stem cell transplantation for sickle cell disease: Progress and challenges

Sickle cell disease (SCD) presents challenges to hematopoietic stem cell transplantation (HSCT), including donor availability and morbidity with age/disease severity. However, severe SCD causes irreversible organ damage that HSCT can mitigate. This benefit must be balanced against preparative regimen toxicity, graft-versus-host disease, and mortality risk. We review efforts to balance HSCT complications with the promise of cure, and knowledge gaps that warrant further investigation. We highlight the burden of SCD, HSCT risks and benefits, and SCD families' approach to this balance. We emphasize the necessity for information exchange to ensure a joint decision-making process between providers and patients.

Acute chest syndrome in sickle cell disease

Acute chest syndrome (ACS) is a leading complication of sickle cell disease (SCD) with significant morbidity and mortality. ACS is the most common cause of death and the second most common cause of hospitalization in patients with SCD. Delineating the specific cause of ACS is often difficult, and multiple risk factors that precipitate ACS frequently coexist. The prominent risk factors include infection, hypoxia, bronchial hyperresponsiveness, the SCD genotype, and opioid use. The key to the successful treatment of ACS is early recognition and initiation of treatment without delay. The main goal is to prevent and treat acute respiratory failure and, thus, minimize irreversible lung damage. This review focuses on the risk factors, pathogenesis, clinical presentation, and management of ACS.

Red blood cell exchange in patients with sickle cell disease-indications and management: a review and consensus report by the therapeutic apheresis subsection of the AABB

BACKGROUND

A prior practice survey revealed variations in the management of patients with sickle cell disease (SCD) and stressed the need for comprehensive guidelines. Here we discuss: 1) common indications for red blood cell exchange (RCE), 2) options for access, 3) how to prepare the red blood cells (RBCs) to be used for RCE, 4) target hemoglobin (Hb) and/or hematocrit (Hct) and HbS level, 5) RBC depletion/RCE, and 6) some complications that may ensue.

STUDY DESIGN AND METHODS

Fifteen physicians actively practicing apheresis from 14 institutions representing different areas within the United States discussed how they manage RCE for patients with SCD.

RESULTS

Simple transfusion is recommended to treat symptomatic anemia with Hb level of less than 9 g/dL. RCE is indicated to prevent or treat complications arising from the presence of HbS. The most important goals are reduction of HbS while also preventing hyperviscosity. The usual goals are a target HbS level of not more than 30% and Hct level of less than 30%.

CONCLUSION

Although a consensus as to protocol details may not be possible, there are areas of agreement in the management of these patients, for example, that it is optimal to avoid hyperviscosity and iron overload, that a target Hb S level in the range of 30% is generally desirable, and that RCE as an acute treatment for pain crisis in the absence of other acute or chronic conditions is ordinarily discouraged.

State of the Art Management of Acute Vaso-occlusive Pain in Sickle Cell Disease

Acute vaso-occlusive crisis (VOC) is a hallmark of sickle cell disease (SCD). Multiple complex pathophysiological processes can result in pain during a VOC. Despite significant improvements in the understanding and management of SCD, little progress has been made in the management of pain in SCD, although new treatments are being explored. Opioids and non-steroidal anti-inflammatory drugs (NSAIDs) remain the mainstay of treatment of VOC pain, but new classes of drugs are being tested to prevent and treat acute pain. Advancements in the understanding of the pathophysiology of SCD and pain and the pharmacogenomics of opioids have yet to be effectively utilized in the management of VOC. Opioid tolerance and opioid-induced hyperalgesia are significant problems associated with the long-term use of opioids, and better strategies for chronic pain therapy are needed. This report reviews the mechanisms of pain associated with acute VOC, describes the current management of VOC, and describes some of the new therapies under evaluation for the management of acute VOC in SCD.