Transfusing children with sickle cell disease using blood group genotyping when the pool of Black donors is limited.

BACKGROUND: Red blood cell transfusion is an effective treatment for patients with sickle cell disease (SCD). Alloimmunization can occur after a single transfusion, limiting further usage of blood transfusion. It is recommended to match for the ABO, D, C, E, and K antigens to reduce risks of alloimmunization. However, availability of compatible blood units can be challenging for blood providers with a limited number of Black donors. STUDY DESIGN AND METHODS: A prospective cohort of 205 pediatric patients with SCD was genotyped for the RH and FY genes. Transfusion and alloimmunization history were collected. Our capacity to find RhCE-matched donors was evaluated using a database of genotyped donors. RESULTS: Nearly 9.8% of patients carried a partial D variant and 5.9% were D-. Only 45.9% of RHCE alleles were normal, with the majority of variants affecting the RH5 (e) antigen. We found an alloimmunization prevalence of 20.7% and a Rh alloimmunization prevalence of 7.1%. Since Black donors represented only 1.40% of all blood donors in our province, D- Caucasian donors were mostly used to provide phenotype matched products. Compatible blood for patients with rare Rh variants was found only in Black donors. A donor with compatible RhCE could be identified for all patients. CONCLUSION: Although Rh-compatible donors were identified, blood units might not be available when needed and/or the extended phenotype or ABO group might not match the patient. A greater effort has to be made for the recruitment of Black donors to accommodate patients with SCD.

A randomized clinical trial of the efficacy and safety of rivipansel for sickle cell vaso-occlusive crisis.

The efficacy and safety of rivipansel, a predominantly E-selectin antagonist, were studied in a phase 3, randomized, controlled trial for vaso-occlusive crisis (VOC) requiring hospitalization (RESET). A total of 345 subjects (204 adults and 141 children) were randomized and 320 were treated (162 with rivipansel, 158 with placebo) with an IV loading dose, followed by up to 14 additional 12-hourly maintenance doses of rivipansel or placebo, in addition to standard care. Rivipansel was similarly administered during subsequent VOCs in the Open-label Extension (OLE) study. In the full analysis population, the median time to readiness for discharge (TTRFD), the primary end point, was not different between rivipansel and placebo (-5.7 hours, P = .79; hazard ratio, 0.97), nor were differences seen in secondary end points of time to discharge (TTD), time to discontinuation of IV opioids (TTDIVO), and cumulative IV opioid use. Mean soluble E-selectin decreased 61% from baseline after the loading dose in the rivipansel group, while remaining unchanged in the placebo group. In a post hoc analysis, early rivipansel treatment within 26.4 hours of VOC pain onset (earliest quartile of time from VOC onset to treatment) reduced median TTRFD by 56.3 hours, reduced median TTD by 41.5 hours, and reduced median TTDIVO by 50.5 hours, compared with placebo (all P < .05). A similar subgroup analysis comparing OLE early-treatment with early-treatment RESET placebo showed a reduction in TTD of 23.1 hours (P = .062) and in TTDIVO of 30.1 hours (P = .087). Timing of rivipansel administration after pain onset may be critical to achieving accelerated resolution of acute VOC. Trial Registration: Clinicaltrials.gov, NCT02187003 (RESET), NCT02433158 (OLE).

COVID-19 and Sickle Cell Disease in the Province of Quebec, Canada: Outcomes after Two Years of the Pandemic.

BACKGROUND: Patients with sickle cell disease (SCD) are considered at higher risk of severe COVID-19 infection. However, morbidity and mortality rates are variable among countries. To date, there are no published reports that document outcomes of SCD patients with COVID-19 in Canada. METHODS: A web-based registry was implemented in June 2020 capturing outcomes of SCD patients with COVID-19 from March 2020 to April 2022 and comparing them to the general population of Quebec, Canada. RESULTS: After 24 months of the pandemic, 185 SCD patients with confirmed SARS-CoV-2 infection were included in the registry. Overall, the population was young (median age 12 years old) and had few comorbidities. No deaths were reported. Risk of hospitalization and admission to intensive care unit (ICU) because of COVID-19 was higher in patients with SCD than in the general population (relative risks (RR) 5.15 (95% confidence interval (95% CI) 3.84-6.91), p ˂ 0.001 and 4.56 (95% CI 2.09-9.93) p ˂ 0.001). A history of arterial hypertension or acute chest syndrome in the past 12 months was associated with a higher risk of severe disease (RR = 3.06 (95% CI 1.85-5.06) p = 0.008 and 2.27 (95% CI 1.35-3.83) p = 0.01). Hospitalized patients had lower hemoglobin F than non-hospitalized patients (12% vs. 17%, p = 0.02). For those who had access to vaccination at the time of infection, 25 out of 26 patients were adequately vaccinated and had mild disease. CONCLUSIONS: The SCD population is at higher risk of severe disease than the general population. However, we report favorable outcomes as no deaths occurred. Registries will continue to be critical to document the impact of novel COVID-19 specific therapy and vaccines for the SCD population.

Acute complications in children with sickle cell disease: Prevention and management.

Sickle cell disease (SCD) is a chronic, multi-system disease that requires comprehensive care. The sickling of red blood cells leads to hemolysis and vascular occlusion. Complications include hemolytic anemia, pain syndromes, and organ damage. Patterns of immigration and an increase in newborn screening mean that paediatric health care providers across Canada, in small and large centres alike, need to be knowledgeable about SCD. This statement focuses on principles of prevention, advocacy, and the rapid treatment of common acute complications. Guidance includes the current status of newborn screening, recommendations for immunizations and antibiotic prophylaxis, and an introduction to hydroxyurea, a medication that reduces both morbidity and mortality in children with SCD. Case vignettes demonstrate principles of care for common acute complications of SCD: vaso-occlusive episodes (VOE), acute chest syndrome (ACS), fever, splenic sequestration, aplastic crises, and stroke. Finally, principles of blood transfusion are highlighted, along with indications for both straight and exchange blood transfusions.

La prévention et la prise en charge des complications aiguës de l'anémie falciforme.

L'anémie falciforme est une maladie multisystémique chronique qui exige des soins globaux. La falciformation des globules rouges entraîne une hémolyse et une occlusion vasculaire. L'anémie hémolytique, les syndromes douloureux et les atteintes organiques en sont des complications. En raison des profils d'immigration et d'une augmentation du dépistage néonatal, les professionnels de la santé pédiatrique du Canada doivent connaître l'anémie falciforme, tant dans les petits que les grands centres. Le présent document de principes porte sur les principes de prévention, de défense d'intérêts et de traitement rapide des complications aiguës courantes de l'anémie falciforme. Les lignes directrices comprennent l'état actuel du dépistage néonatal, les recommandations en matière de vaccination et de prophylaxie antibiotique et une introduction à l'hydroxyurée, un médicament qui réduit à la fois la morbidité et la mortalité chez les enfants atteints d'anémie falciforme. Des scénarios cliniques démontrent les principes de soins en cas de complications aiguës courantes : les épisodes vaso-occlusifs, le syndrome thoracique aigu, la fièvre, la séquestration splénique, les crises aplasiques et les accidents vasculaires cérébraux. Enfin, les principes de transfusion sanguine sont présentés, de même que les indications de transfusion simple ou d'exsanguinotransfusion.

Current applications for measuring pediatric intima-media thickness.

Intima-media thickness is a known subclinical radiologic marker of the early manifestations of atherosclerotic disease. It is the thickness of the vessel wall, most often the carotid artery. Intima-media thickness is measured on conventional US manually or automatically. Other measurement techniques include radiofrequency US. Because there is variation in its measurement, especially in children, several recommendations have been set to increase the measurement's validity and comparability among studies. Despite these recommendations, several pitfalls should be avoided, and quality control should be performed to avoid erroneous interpretation. This article summarizes current literature in relation to the clinical applications for intima-media thickness measurement in children with known risk factors such as obesity, liver steatosis, hypercholesterolemia, diabetes, hypertension, systemic inflammatory diseases, cancer survival, kidney and liver transplant, and sickle cell disease or beta thalassemia major. Most potential indications for intima-media thickness measurement remain in the research domain and should be interpreted combined with other markers. The objective of diagnosing an increased intima-media thickness is to start a multidisciplinary treatment approach to prevent disease progression and its sequelae in adulthood.

Poor outcome after hematopoietic stem cell transplantation of patients with unclassified inherited bone marrow failure syndromes.

Classification of inherited bone marrow failure syndromes (IBMFSs) according to clinical and genetic diagnoses enables proper adjustment of treatment. Unfortunately, 30% of patients enrolled in the Canadian Inherited Marrow Failure Registry (CIMFR) with features suggesting hereditability could not be classified with a specific syndromic diagnosis. We analyzed the outcome of hematopoietic stem cell transplantation (HSCT) in unclassified IBMFSs (uIBMFSs) and the factors associated with outcome. Twenty-two patients with uIBMFSs and 70 patients with classified IBMFSs underwent HSCT. Five-year overall survival of uIBMFS patients after HSCT was inferior to that of patients with classified IBMFSs (56% vs 76.5%). The outcome of patients with uIBMFS who received cord blood was significantly lower than that of patients who received other stem cell sources (14.8% vs 90.9%). Engraftment failure was higher among patients with uIBMFS who received cord blood than those who received bone marrow. None of the following factors were significantly associated with poor survival: transfusion load, transplant indication, the intensity of conditioning regimen, human leukocyte antigen-identical sibling/alternative donor. We suggest that identifying the genetic diagnosis is essential to modulate the transplant procedure including conditioning agents and stem cell sources for better outcome and the standard cord blood transplantation (CBT) should be avoided in uIBMFS.

Evaluation of Vaso-occlusive Crisis Management With Patient-Controlled Analgesia in Children With Sickle Cell Disease Requiring Hospitalization.

OBJECTIVE: The aim of this study was to review the use of patient-controlled analgesia (PCA) in sickle cell disease (SCD) for pediatric patients with vaso-occlusive crisis (VOC) in our institution and to compare the effect of early vs late PCA start on pain relief and LOS. METHODS: This retrospective study included all pediatric patients treated with PCA for a severe VOC from 2010 to 2016. "Early-PCA" was defined as start of PCA within 48 hours of arrival. Time to reach adequate analgesia was defined as the time to reach 2 consecutive pain scores less than 5/10 at 4-hour interval. RESULTS: During the study period, 46 patients presented 87 episodes of VOC treated with PCA. Sixty-three patients with VOC were treated with Early-PCA and 24 with Late-PCA. Both groups were comparable except for median pain score at admission; the Early-PCA group had higher scores: 9.0/10 vs 7.0/10. Time to reach adequate analgesia could be evaluated only in a subset of patients (n = 32) but was shorter in the Early-PCA group with a median difference of 41.0 hours (95% CI -82.0 to -6.0). Early-PCA was associated with a median reduction in LOS of 3.4 days (95% CI -4.9 to -1.9). There was no difference between the 2 groups in terms of side effects and occurrence of acute chest syndrome during hospitalization. CONCLUSIONS: In this study, a reduced time to reach adequate analgesia and LOS was noted in the Early-PCA group for severe VOC. A prospective study is required to confirm these results.

Quality of life is an important indication for second-line treatment in children with immune thrombocytopenia.

BACKGROUND: The decision to initiate second-line treatment in children with immune thrombocytopenia (ITP) is complex and involves many different factors. METHODS: In this prospective, observational, longitudinal cohort study of 120 children from 21 centers, the factors contributing to the decision to start second-line treatments for ITP were captured. At study entry, clinicians were given a curated list of 12 potential reasons the patient required a second-line treatment. Clinicians selected all that applied and ranked the top three reasons. RESULTS: Quality of life (QOL) was the most frequently cited reason for starting a second-line therapy. Clinicians chose it as a reason to treat in 88/120 (73%) patients, as among the top three reasons in 68/120 (57%), and as the top reason in 32/120 (27%). Additional factors ranked as the top reason to start second-line treatment included severity of bleeding (22/120, 18%), frequency of bleeding (19/120, 16%), and severity of thrombocytopenia (18/120, 15%). Patients for whom QOL (p = .006) or sports participation (p = .02) were ranked reasons were more likely to have chronic ITP, whereas those for whom severity (p = .003) or frequency (p = .005) of bleeding were ranked reasons were more likely to have newly diagnosed or persistent ITP. Parental anxiety, though rarely the primary impetus for treatment, was frequently cited (70/120, 58%) as a contributing factor. CONCLUSION: Perceived QOL is the most frequently selected reason pediatric patients start second-line therapies for ITP. It is critical that studies of treatments for childhood ITP include assessments of their effects on QOL.

Is Busulfan Clearance Different in Patients With Sickle Cell Disease? Let's Clear Up That Case With Some Controls.

In busulfan-based conditioning regimen for hematopoietic stem cell transplantation in children, accurate a priori determination of the first dose is important because of its narrow therapeutic window. Sickle cell disease (SCD) influences pharmacokinetics of the commonly used drugs by affecting organs responsible for drug metabolism and elimination. This pharmacokinetics study assesses the influence of SCD on the metabolic pathway of busulfan that is mainly metabolized in the liver. In this retrospective cross-sectional case-control study, 16 patients with SCD were matched to 50 patients without SCD on known busulfan clearance's covariates (glutathione-S-transferase alpha1 polymorphisms, age, weight). Clearance of the first dose of busulfan was not significantly different independently of genetic or anthropometric factors in patients with or without SCD.

The timing of cyclic cytotoxic chemotherapy can worsen neutropenia and neutrophilia.

Despite recent advances in immunotherapies, cytotoxic chemotherapy continues to be a first-line treatment option for the majority of cancers. Unfortunately, a common side effect in patients undergoing chemotherapy treatment is neutropenia. To mitigate the risk of neutropenia and febrile neutropenia, prophylactic treatment with granulocyte-colony stimulating factor (G-CSF) is administered. Extensive pharmacokinetic/pharmacodynamic modelling of myelosuppression during chemotherapy has suggested avenues for therapy optimization to mitigate this neutropenia. However, the issue of resonance, whereby neutrophil oscillations are induced by the periodic administration of cytotoxic chemotherapy and the coadministration of G-CSF, potentially aggravating a patient's neutropenic/neutrophilic status, is not well-characterized in the clinical literature. Here, through analysis of neutrophil data from young acute lymphoblastic leukaemia patients, we find that resonance is occurring during cyclic chemotherapy treatment in 26% of these patients. Motivated by these data and our previous modelling studies on adult lymphoma patients, we examined resonance during treatment with or without G-CSF. Using our quantitative systems pharmacology model of granulopoiesis, we show that the timing of cyclic chemotherapy can worsen neutropenia or neutrophilia, and suggest clinically-actionable schedules to reduce the resonant effect. We emphasize that delaying supportive G-CSF therapy to 6-7 days after chemotherapy can mitigate myelosuppressive effects. This study therefore highlights the importance of quantitative systems pharmacology for the clinical practice for developing rational therapeutic strategies.

Comparison of two vitamin D supplementation strategies in children with sickle cell disease: a randomized controlled trial.

Previously, we showed that nearly 70% of children followed in our sickle cell disease (SCD) clinic were vitamin D- deficient and had low vitamin intake with poor use of supplements. We compared the change in serum 25-hydroxyvitamin D [25(OH)D], safety and clinical impact of two vitamin D supplementation regimens in children with SCD. Children (5-17 years, all genotypes) were randomized to a single bolus of vitamin D3 (300 000 IU; n = 18) or placebo (n = 20). All children received a prescription for daily 1 000 IU vitamin D3 . Serum 25(OH)D and calcium, urinary calcium/creatinine ratio, musculoskeletal pain, quality of life, haematology and bone markers were assessed at baseline and three months post intervention. Bolus administration led to a greater rise in 25(OH)D levels from baseline compared to placebo (20 ± 16 nmol/l vs. 2 ± 19 nmol/l; P = 0·003) and correction of vitamin D deficiency. No hypercalcaemia nor hypercalciuria occurred during the study, but more children in the bolus group experienced gastrointestinal symptoms within the first month (P = 0·04). There were no differences between groups for other outcomes. The use of a high-dose vitamin D bolus combined with daily 1 000 IU vitamin D3 was more efficient in raising 25(OH)D levels than daily supplementation alone in children with SCD.

Changes in hair cortisol and self-reported stress measures following mindfulness-based stress reduction (MBSR): A proof-of-concept study in pediatric hematology-oncology professionals.

BACKGROUND AND PURPOSE: Little data is available on the effect of mindfulness amongst pediatric hematology-oncology professionals. The purpose was to further document change in biological and psychological stress following a mindfulness-based stress reduction (MBSR) program. MATERIALS AND METHODS: We led two pre-post interventional studies (n = 12 and n = 25) and measured changes on hair cortisol concentrations, perceived stress, psychological distress and burnout. RESULTS: Professionals did not change on biological stress (d = 0.04), but improved on self-reported measures (median d = 0.58). Effects were maintained over 3 months for psychological distress, anxiety, depression, and burnout (median d = 0.66). Effects were larger if trainees participated to the retreat and if they reported higher baseline perceived stress. CONCLUSION: In pediatric hematology-oncology professionals, an MBSR program was related with improvements in self-reported stress over 3 months. Components of the program and characteristics of trainees may influence the impact of MBSR.

Evaluation of a clinical protocol using intranasal fentanyl for treatment of vaso-occlusive crisis in sickle cell patients in the emergency department.

BACKGROUND: Vaso-occlusive crisis (VOC) is one of the most frequent causes of emergency visits and admission in children with sickle cell disease (SCD). OBJECTIVES: This study aims to evaluate whether the use of a new pain management pathway using intranasal (IN) fentanyl from triage leads to improved care, translated by a decrease in time to first opiate dose. METHODS: We performed a retrospective chart review of patients with SCD who presented to the emergency department (ED) with VOC, in the period pre- (52 patients) and post- (44 patients) implementation period of the protocol. Time to first opiate was the primary outcome and was evaluated pre- and postimplementation. Patients received a first opiate dose within 52.3 minutes of registration (interquantile range [IQR] 30.6, 74.6), corresponding to a 41.4-minute reduction in the opiate administration time (95% confidence interval [CI] -56.1, -27.9). There was also a 43% increase in the number of patients treated with a nonintravenous (IV) opiate as first opiate dose (95% CI 26, 57). In patients who were discharged from the ED, there was a 49% decrease in the number of IV line insertions (95% CI -67, -22). There was no difference in the hospitalization rates (difference of 6 [95% CI -13, 25]). CONCLUSIONS: This study validates the use of our protocol using IN fentanyl as first treatment of VOC in the ED by significantly reducing the time to first opiate dose and the number of IVs.

Fatigue in children and adolescents with immune thrombocytopenia.

Immune thrombocytopenia (ITP), an acquired autoimmune disorder of low platelets and risk of bleeding, has a substantial impact on health-related quality of life (HRQoL). Patients with ITP often report significant fatigue, although the pathophysiology of this is poorly understood. In this observational cohort of 120 children receiving second-line therapies for ITP, we assessed reports of fatigue using the Hockenberry Fatigue Scale. Children and adolescents with ITP reported a similarly high level of fatigue with 54% (29/54) of children and 62% (26/42) of adolescents reporting moderate-to-severe fatigue. There was no correlation between fatigue and age or gender. Adolescents with newly diagnosed and persistent ITP had higher mean fatigue scores than those with chronic ITP (P = 0·03). Fatigue significantly improved in children and adolescents by 1 month after starting second-line treatments, and this improvement continued to be present at 12 months after starting treatment. Fatigue scores at all time-points correlated with general HRQoL using the Kids ITP Tool, but did not correlate with bleeding symptoms, platelet count, or platelet response to treatment. Fatigue is common in children and adolescents with ITP and may benefit from ITP-directed treatment even in the absence of bleeding symptoms.

Fusobacterium nucleatum Multiple Liver Abscesses in an Adolescent With Hemoglobin SC Disease.

Liver abscesses are poorly known in sickle cell disease. We report here multiple liver abscesses occurring in a 17-year-old patient with hemoglobin SC disease. A Fusobacterium nucleatum was identified on cyst puncture. Such complications have been described in only 11 children and young adults with hemoglobin SS/Sß-thalassemia diseases. Fusobacterium species are the most frequent pathogens reported and require anaerobic culture to be identified.

Androgen therapy in inherited bone marrow failure syndromes: analysis from the Canadian Inherited Marrow Failure Registry.

Progressive cytopenia is a serious complication among paediatric patients with inherited bone marrow failure syndromes (IBMFS). Androgens have been used to improve blood counts in different bone marrow failure conditions. Little is known about efficacy and toxicity with new androgens (i.e., danazol) in different types of IBMFS. We identified 29 patients from the Canadian Inherited Marrow Failure Registry, who received oxymetholone or danazol. Sixteen (55%) had haematological response including patients with unclassified IBMFS (45%). Danazol showed a better toxicity profile and similar efficacy compared to oxymetholone. Androgens are an effective and safe option to ameliorate bone marrow failure in IBMFS.

Duration of neonatal oxygen supplementation, erythropoiesis and blood pressure in young adults born preterm.

BACKGROUND: Although erythropoiesis is impaired and anaemia frequent in neonates born preterm, haematopoiesis in adults born preterm has not been previously studied. OBJECTIVE: We, thus, aimed to evaluate haemoglobin and erythropoietin levels in young adults born preterm, to identify neonatal events associated with erythropoiesis in adulthood and to examine the relationships of haemoglobin levels with respiratory function and blood pressure. METHODS: We assessed a cohort of 101 young adults (ages 18-29) born preterm (≤29 weeks of gestation), in comparison to 105 full-term controls. We measured haemoglobin, erythropoietin levels and blood pressure. We also assessed respiratory function using spirometry. RESULTS: Compared with controls, tobacco use and sex-adjusted haemoglobin levels were 5.3 (95% CI 2.9 to 7.7) g/L higher in preterm-born individuals, but erythropoietin levels were similar. Duration of oxygen supplementation in the neonatal period was independently associated with higher haemoglobin levels in the preterm group. In young adults born preterm with bronchopulmonary dysplasia, airflow limitation was associated with higher haemoglobin levels. Both systolic (SBP) and diastolic (DBP) blood pressure were increased in individuals born preterm (p=0.042 and p=0.0008, respectively). Higher haemoglobin levels were associated with higher SBP and DBP, independently of term or preterm status. Mediation analysis suggests that haemoglobin increase contributes to 37% and 32% of the effect of preterm birth on SBP and DBP, respectively. CONCLUSIONS: Haemoglobin levels are higher in young adults born preterm, while erythropoietin levels are similar, especially in case of bronchopulmonary dysplasia and airflow limitation, and haemoglobin increase is associated with elevated blood pressure in this population.