Prevalence of Duffy null and its impact on hydroxyurea in young children with sickle cell disease in the United States.

Consistent with studies showing a high prevalence of the Duffy null phenotype among healthy Black Americans, this retrospective study found that Duffy null was present in >75% of a young and contemporary cohort of children with sickle cell disease (SCD) in the United States. Despite the potential for this phenotype to impact absolute neutrophil counts, hydroxyurea (HU) dosing, and outcomes, it was not associated with being prescribed a lower HU dose or having increased acute SCD visits early in the HU treatment course. Future studies are needed to confirm these findings in older children with SCD.

Impact of community health workers on quality of life in adolescents and young adults with sickle cell disease: The SHIP-HU study.

Health-related quality of life (HRQoL) is an important outcome for patients with sickle cell disease (SCD). It is often poor compared with other chronic medical conditions or measured as a multidomain disease-specific construct. We previously reported outcomes in the Start Healing in Patients with Hydroxyurea (SHIP-HU) randomized controlled trial in adolescents and adults with SCD at six clinical sites. Besides the primary outcomes, we also measured HRQoL as a secondary outcome. Patients in the intervention arm were each assigned community health workers (CHWs) who provided case management services. CHW services were independent of medical management, and medical managers were blinded to the study arm. Patients in the control arm received only standard of care. We hypothesized that having a CHW would improve HRQoL in patients enrolled in SHIP-HU. We did not find significant differences between domains of HRQoL in the two study arms. Possible explanations include selection bias of enrolled versus unenrolled patients, selection bias of sites, medical providers and medical management, enforced blinding, and a lack of cooperation between medical managers and CHWs. The importance of CHWs and HRQoL is nonetheless recognized based on the literature. Future interventions on HRQoL in SCD should consider alternative study designs and multimodal interventions.

Vaso-occlusive crisis pain intensity, frequency, and duration: which best correlates with health-related quality of life in adolescents and adults with sickle cell disease?

ABSTRACT: In a cross-sectional analysis of baseline data from a randomized clinical trial, we studied 198 adolescents and adults aged 15+ with sickle cell disease. Interest was in assessing the relative strengths of the relationship of vaso-occlusive crisis (VOC) pain domains of intensity, frequency, and duration, with health-related quality of life (HRQOL). Variation in psychosocial, physical function, and pain expression domains of HRQOL was partially explained by frequency, intensity, and duration of VOC pain, separately and together, over and above differences in age, sex, genotype, and organ system damage. However, no single domain measure accounted for more than an additional partial R2 of 12.5% alone. Vaso-occlusive crisis pain frequency explained the most variation, when simultaneously considering VOC intensity and duration, except for stiffness , where duration was most predictive. Yet VOC pain intensity, and even VOC duration, also contributed to variability in HRQOL. We recommend that for most purposes, because all 3 VOC pain domains contribute to variability in HRQOL, all 3 domains should be assessed and interventions should be targeted to improve all 3 domains to maximize HRQOL outcomes (Clinical Trial Registration: ClinicalTrials.gov Identifier: NCT02197845 ).

Sickle Cell Disease Treatment with Arginine Therapy (STArT): study protocol for a phase 3 randomized controlled trial.

BACKGROUND: Despite substantial illness burden and healthcare utilization conferred by pain from vaso-occlusive episodes (VOE) in children with sickle cell disease (SCD), disease-modifying therapies to effectively treat SCD-VOE are lacking. The aim of the Sickle Cell Disease Treatment with Arginine Therapy (STArT) Trial is to provide definitive evidence regarding the efficacy of intravenous arginine as a treatment for acute SCD-VOE among children, adolescents, and young adults. METHODS: STArT is a double-blind, placebo-controlled, randomized, phase 3, multicenter trial of intravenous arginine therapy in 360 children, adolescents, and young adults who present with SCD-VOE. The STArT Trial is being conducted at 10 sites in the USA through the Pediatric Emergency Care Applied Research Network (PECARN). Enrollment began in 2021 and will continue for 5 years. Within 12 h of receiving their first dose of intravenous opioids, enrolled participants are randomized 1:1 to receive either (1) a one-time loading dose of L-arginine (200 mg/kg with a maximum of 20 g) administered intravenously followed by a standard dose of 100 mg/kg (maximum 10 g) three times a day or (2) a one-time placebo loading dose of normal saline followed by normal saline three times per day at equivalent volumes and duration as the study drug. Participants, research staff, and investigators are blinded to the participant's randomization. All clinical care is provided in accordance with the institution-specific standard of care for SCD-VOE based on the 2014 National Heart, Lung, and Blood Institute guidelines. The primary outcome is time to SCD-VOE pain crisis resolution, defined as the time (in hours) from study drug delivery to the last dose of parenteral opioid delivery. Secondary outcomes include total parental opioid use and patient-reported outcomes. In addition, the trial will characterize alterations in the arginine metabolome and mitochondrial function in children with SCD-VOE. DISCUSSION: Building on the foundation of established relationships between emergency medicine providers and hematologists in a multicenter research network to ensure adequate participant accrual, the STArT Trial will provide definitive information about the efficacy of intravenous arginine for the treatment of SCD-VOE for children. TRIAL REGISTRATION: The STArT Trial was registered in ClinicalTrials.gov on April 9, 2021, and enrollment began on June 21, 2021 (NCT04839354).

Return visit rates after an emergency department discharge for children with sickle cell pain episodes.

BACKGROUND: High return visit rates after hospitalization for people with sickle cell disease (SCD) have been previously established. Due to a lack of multicenter emergency department (ED) return visit rate data, the return visit rate following ED discharge for pediatric SCD pain treatment is currently unknown. PROCEDURE: A seven-site retrospective cohort study of discharged ED visits for pain by children with SCD was conducted using the Pediatric Emergency Care Applied Research Network Registry. Visits between January 2017 and November 2021 were identified using previously validated criteria. The primary outcome was the 14-day return visit rate, with 3- and 7-day rates also calculated. Modified Poisson regression was used to analyze associations for age, sex, initial hospitalization rate, and a visit during the COVID-19 pandemic with return visit rates. RESULTS: Of 2548 eligible ED visits, approximately 52% were patients less than 12 years old, 50% were female, and over 95% were non-Hispanic Black. The overall 14-day return visit rate was 29.1% (95% confidence interval [CI]: 27.4%-30.9%; site range 22.7%-31.7%); the 7- and 3-day return visit rates were 23.0% (95% CI: 21.3%-24.6%) and 16.7% (95% CI: 15.3%-18.2%), respectively. Younger children had slightly lower 14-day return visit rates (27.3% vs. 31.1%); there were no associations for site hospitalization rate, sex, and a visit occurring during the pandemic with 14-day returns. CONCLUSION: Nearly 30% of ED discharged visits after SCD pain treatment had a return visit within 14 days. Increased efforts are needed to identify causes for high ED return visit rates and ensure optimal ED and post-ED care.

Prevalence and risk factors for pulmonary embolism in children with sickle cell disease: an institutional retrospective cohort study.

The study was conducted to examine prevalence of pulmonary embolism in children with sickle cell disease (SCD) and identify potential risk factors associated with pulmonary embolism in a single tertiary paediatric centre. Children with SCD between 0 and 21 years of age from January 2010 to January 2021 were included. Pulmonary embolism was initially identified using International Classification of Diseases (ICD)-9 or 10 codes and confirmed with manual chart review of identified cases. Logistic regression analysis was performed to assess association between SCD specific and general thrombotic risk factors and pulmonary embolism. We identified 492 unique patients with SCD with a median age of 11 years (interquartile range: 4-18). A total of eight (1.6%) patients developed a pulmonary embolism. Patients with pulmonary embolism were significantly older (median, interquartile range: 20.5, 14-21 years) than patients without pulmonary embolism (median, interquartile range: 10, 4-17 years). Central nervous system (CNS) vasculopathy and erythrocytapheresis were significantly associated with pulmonary embolism on univariable logistic regression analysis. A previous diagnosis of deep vein thrombosis (DVT) was significantly more common among patients with pulmonary embolism than among those without pulmonary embolism (50 vs. 5.2%; P  < 0.0001). Prevalence of pulmonary embolism in children with SCD was high. Risk factors associated with pulmonary embolism in this study such as CNS vasculopathy or erythrocytapheresis could suggest that the risk for pulmonary embolism in SCD may be related to the severity of disease state. Future studies are needed on pulmonary embolism prevention strategies.

Prevalence and Risk Factors for Pulmonary Embolism in Pediatric Sickle Cell Disease: A National Administrative Database Study.

Patients with sickle cell disease (SCD) have a high risk for venous thromboembolism which is associated with increased risk of mortality. Studies examining risk of pulmonary embolism (PE) in children with SCD are lacking. This study was conducted in children with SCD between 0-21 years of age using a nationwide administrative database in the United States- Pediatric Health Information System (PHIS) from January 2010 to June 2021. Diagnostic codes and imaging, procedure, and pharmaceutical billing codes were used to identify PE and potential clinical, demographic, and utilization risk factors. Logistic regression analyses were performed to assess association between risk factors and PE. We identified 22,631 unique patients with SCD with a median age of 10.8 years (range: <0.1-20.9). A total of 120 (0.53%) patients developed a PE with median age of 17.4 years (range: 6.6-20.9) at PE diagnosis. Patients with PE had longer hospitalization and more frequent ICU admissions than patients without PE (p < 0.001). Risk factors significantly associated with PE on multivariable analysis included older age, prior history of central venous line (CVL), acute chest syndrome, and apheresis. Mortality was not significantly different between those with and without PE. The prevalence of PE in hospitalized children with SCD was estimated to be 0.53%. Patients with PE had higher healthcare utilization characteristics. Factors significantly associated with PE suggest that the risk for PE in SCD may be related to the severity of disease state. Future trials are needed for risk stratification and PE prevention strategies in children with SCD.

Pediatric Sickle Cell Disease Patients on Hydroxyurea Have Higher Rates of Surgical Splenectomy.

INTRODUCTION: We sought to investigate whether hydroxyurea therapy is associated with the need for surgical splenectomy among patients with sickle cell disease (SCD). We hypothesized that as hydroxyurea gained widespread use, surgical splenectomy among pediatric patients with SCD occurred at a higher rate and older age among those taking hydroxyurea. METHODS: In this retrospective cross-sectional study, the Pediatric Health Information System was queried for all SCD International Classification of Diseases 9/10 diagnosis codes and splenectomy procedure codes from January 1, 2005, to December 31, 2020. Hydroxyurea use was defined as at least one hospital admission with hydroxyurea listed as a medication. The rates of surgical splenectomy, age at splenectomy, hospital length of stay, and incidence of blood transfusion during the splenectomy admission were compared among patients receiving hydroxyurea versus those not receiving hydroxyurea. Additional subanalysis was performed in the Hemoglobin-SS, Hemoglobin-SC, and Other cohorts separately. RESULTS: During the study period, 28,520 patients were identified. All patients with SCD receiving hydroxyurea had a significantly higher rate of surgical splenectomy compared with the nontreatment group (7.2% versus 3.2%, P = 0.01). The age at surgical splenectomy was significantly younger among Hemoglobin-SS patients receiving hydroxyurea (5.7 [5.1, 6.4] y versus 6.6 [5.8, 7.4] y; P < 0.01). There were no significant differences in length of stay or incidence of blood transfusion during the surgical splenectomy admission between treatment groups. CONCLUSIONS: Hydroxyurea use in children is associated with higher rates of surgical splenectomy and occurs at a younger age in the Hemoglobin-SS population. Although these findings warrant further investigation for causality, it provides useful information to clinicians and patients alike, allowing for more informed decision-making.

Satisfaction and access to care for adults and adolescents with sickle cell disease: ASCQ-Me quality of care and the SHIP-HU study.

A lack of adult sickle cell providers has long been blamed for poor satisfaction and access to specialty care for adults with sickle cell disease (SCD). We were interested in comparing how adolescent and adult patients already in established SCD centers perceived access and quality of care. Hydroxyurea-eligible patients aged 15 years and older were enrolled in the Start Healing in Patients with Hydroxyurea trial, which required them to be affiliated with a SCD specialist. Patients were seen in one of three adult-oriented specialty clinic sites or one of three pediatric-oriented sites. At baseline, patients completed the Adult Sickle Cell Quality of Life Measurement Information System measure as part of a survey battery. Patients treated at adult clinic sites reported being less able to get timely ambulatory appointments (p = .004). They reported emergency department (ED) wait times of >1 h far more often (47.7 vs. 19.3%, p = .0048). They reported less overall satisfaction with care (7.47 vs. 8.77, p < .0001), and less satisfaction with care in the ED (2.88 vs. 3.4, p = .0068. Ambulatory satisfaction was no different between pediatric site versus adult site patients. Poorer systems of care appeared to underlie reported differences, rather than differences in biopsychosocial determinants. Even among specialty-care-affiliated SCD patients, those seen in adult clinics reported worse access to care and lower satisfaction with care than patients seen in pediatric clinics. In addition to increasing the number of adult SCD providers and better preparing pediatric SCD patients to transfer to adult programs, SCD clinical caregivers must also improve aspects of adult care quality to meet reasonable patient expectations of timeliness and interpersonal aspects of care quality.

A randomised controlled provider-blinded trial of community health workers in sickle cell anaemia: effects on haematologic variables and hydroxyurea adherence.

Hydroxyurea (hydroxycarbamide) (HU) for sickle cell anaemia (SCA) is underutilised. Case management is an evidence-based health management strategy and in this regard patient navigators (PNs) may provide case management for SCA. We hypothesised that HU-eligible patients exposed to PNs would have improved indicators of starting HU and HU adherence. We randomised 224 HU-eligible SCA adults into the Start Healing in Patients with Hydroxyurea (SHIP-HU) Trial. All patients received care from trained physicians using standardised HU prescribing protocols. Patients in the Experimental arm received case management and education from PNs through multiple contacts. All other patients were regarded as the Control arm and received specialty care alone. Study physicians were blinded to the study arms and did not interact with PNs. At baseline, 6 and 12 months we assessed and compared laboratory parameters and HU adherence indicators. Experimental patients had higher 6-month mean fetal haemoglobin (HbF) levels than controls. But at 12 months, mean HbF was similar, as were white blood cell count, absolute neutrophil count, total haemoglobin, platelet count and mean corpuscular volume. At 12 months there were fewer experimental patients missing HU doses than controls (mean 1·8 vs. 4·5, P = 0·0098), and more recent HU prescriptions filled than for controls (mean 53·8 vs. 92 days, median 27·5 vs. 62 days, P = 0·0082). Mean HU doses were largely similar. We detected behavioural improvements in HU adherence but no haematological improvements by adding PNs to specialty care.

A comparison of robotic-assisted splenectomy and laparoscopic splenectomy for children with hematologic disorders.

INTRODUCTION: Laparoscopic splenectomy (LS) is the standard of care for hematologic disorders requiring splenectomy. Less is known about the outcomes following robotic-assisted splenectomy (RS) for this indication. Our aim was to describe outcomes of RS to LS in pediatric patients with hematologic disorders in our institution. METHODS: A single institution retrospective review was performed of pediatric patients undergoing LS vs. RS from 2014 to 2019. Patient demographics, diagnosis, spleen size, hospital length of stay (LOS), operative time, post-operative opioid use, and hospital charges were evaluated. Standard univariate analyses were performed. RESULTS: Twenty-four patients were included in the study (14 LS, 10 RS). The mean spleen size at the time of surgery was larger in the RS group compared to LS (14.5 cm vs. 12.2 cm, p = 0.03). Operative time between the two cohorts was comparable (RS 140.5 vs LS 154.9 min). Median LOS for RS was shorter than LS (2.1 vs. 3.2 days, p = 0.02). Cumulative postoperative opioid analgesic requirements were not significantly different between the groups (17.4 mg vs. 30.5 mg). The median hospital charges, including the surgical procedure and hospital stay were higher in the RS group ($44,724 RS vs $30,255 LS, p = 0.01). CONCLUSION: Robotic splenectomy is a safe and feasible option for pediatric patients with hematologic disorders, and was associated with decreased LOS but higher charges compared to laparoscopic splenectomy. Further studies are required to delineate the optimal use and potential benefits of robot-assisted surgical techniques in children. LEVEL OF EVIDENCE: II.

Successful Liver Transplantation for Adolescent Patient With Pyruvate Kinase Deficiency-induced Cirrhosis.

We present the case of a successful liver transplant in a young adult patient with cholestasis and cirrhosis secondary to severe pyruvate kinase (PK) deficiency. Liver transplant resulted in resolution of liver dysfunction, decreased need for blood transfusions and eligibility for bone marrow transplantation. This case represents the third reported patient in the literature with severe PK deficiency who successfully underwent liver transplant as a result of profound cholestasis and liver failure. Explant pathology demonstrated a lack of significant iron deposition indicating that PK deficiency predisposes the liver to injury independent of transfusion-related iron overload.

Nitric oxide for inhalation in the acute treatment of sickle cell pain crisis: a randomized controlled trial.

CONTEXT: Inhaled nitric oxide has shown evidence of efficacy in mouse models of sickle cell disease (SCD), case series of patients with acute chest syndrome, and 2 small placebo-controlled trials for treatment of vaso-occlusive pain crisis (VOC). OBJECTIVE: To determine whether inhaled nitric oxide gas reduces the duration of painful crisis in patients with SCD who present to the emergency department or hospital for care. DESIGN, SETTING, AND PARTICIPANTS: Prospective, multicenter, double-blind, randomized, placebo-controlled clinical trial for up to 72 hours of inhaled nitric oxide gas vs inhaled nitrogen placebo in 150 participants presenting with VOC of SCD at 11 centers between October 5, 2004, and December 22, 2008. Intervention Inhaled nitric oxide gas vs inhaled nitrogen placebo. MAIN OUTCOME MEASURES: The primary end point was the time to resolution of painful crisis, defined by (1) freedom from parenteral opioid use for 5 hours; (2) pain relief as assessed by visual analog pain scale scores of 6 cm or lower (on 0-10 scale); (3) ability to walk; and (4) patient's and family's decision, with physician consensus, that the remaining pain could be managed at home. RESULTS: There was no significant change in the primary end point between the nitric oxide and placebo groups, with a median time to resolution of crisis of 73.0 hours (95% confidence interval [CI], 46.0-91.0) and 65.5 hours (95% CI, 48.1-84.0), respectively (P = .87). There were no significant differences in secondary outcome measures, including length of hospitalization, visual analog pain scale scores, cumulative opioid usage, and rate of acute chest syndrome. Inhaled nitric oxide was well tolerated, with no increase in serious adverse events. Increases in venous methemoglobin concentration confirmed adherence and randomization but did not exceed 5% in any study participant. Significant increases in plasma nitrate occurred in the treatment group, but there were no observed increases in plasma or whole blood nitrite. CONCLUSION: Among patients with SCD hospitalized with VOC, the use of inhaled nitric oxide compared with placebo did not improve time to crisis resolution. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00094887.

Apparent desaturation on pulse oximetry because of hemoglobinopathy.

Hemoglobinopathies are an uncommon cause of cyanosis and low oxygen saturation on pulse oximetry. However, when they do occur, they can present a complex clinical scenario for the emergency physician. We report the index case of a previously undescribed hemoglobinopathy that presented to the pediatric emergency department. The evaluation and management of the cyanotic/hypoxic child and review of hemoglobinopathies are presented here.

Real-Time PCR: an Effective Tool for Measuring Transduction Efficiency in Human Hematopoietic Progenitor Cells.

Accurate measurement of gene transfer into hematopoietic progenitor cells is an essential prerequisite for assessing the utility of gene therapy approaches designed to correct hematologic defects. We developed a reliable method to measure transduction efficiency at the level of the progenitor cell with real-time polymerase chain reaction (PCR) analysis of individual progenitor-derived colonies. We hypothesized that this method would demonstrate better sensitivity and specificity than are currently achievable with conventional PCR. An oncoretroviral vector containing the enhanced green fluorescent protein was used to transduce human CD34+ cells derived from bone marrow or granulocyte-colony-stimulating factor-mobilized peripheral blood. Progenitor assays were set up and colonies plucked after visualization by fluorescence microscopy. By analyzing microscopically identified fluorescent samples and nontransduced samples, we calculated an overall sensitivity and specificity of 90.2 and 95.0%, respectively. Real-time PCR had higher specificity and sensitivity than conventional PCR as analyzed by generalized linear models (P = 0.002 and P = 0.019, respectively). In conclusion, we found real-time PCR to have superior sensitivity and specificity compared to conventional PCR in determining transduction efficiency of hematopoietic progenitor cells.