Impact of telehealth visits on hydroxyurea response in sickle cell anemia.

BACKGROUND: It is important to ensure access to hydroxyurea (HU) for patients with sickle cell anemia (SCA) living in rural areas. The University of Alabama at Birmingham (UAB) Pediatric Sickle Cell program's satellite clinics reduce the barrier of transportation to the university-based clinic. However, as compared with the university clinic, these satellite clinics do not offer immediate access to HU dosing laboratory results and a nurse clinician calls families with HU dose adjustments after the clinic visit. This study evaluated the impact of telehealth dosing adjustments on HU laboratory and clinical response as compared with university-based patients. METHODS: A one-year retrospective chart review was performed to evaluate HU laboratory and clinical response based on clinic location and socioeconomic status for patients with SCA. We identified the number of clinic and acute care visits for one year and calculated the mean complete blood count and fetal hemoglobin (HbF) values for each patient. RESULTS: We identified 107 academic center participants with SCA-prescribed HU and 65 satellite clinic participants. The mean age of participants was 11 ± 5 years. We identified no difference in HbF (13.3 ± 0.7 vs 11.7 ± 0.8, P = 0.13), Hb (8.46 ± 1.1 vs 8.55 ± 1.1, P = 0.59), mean corpuscular volume (91.0 ± 10.6 vs 91.7 ± 9.5, P = 0.67), or absolute neutrophil count (4.85 ± 2.3 vs 4.87 ± 2.3, P = 0.95) when comparing Birmingham versus satellite clinics. We also identified no difference in hospital admissions (0.99 ± 0.1 versus 0.85 ± 0.2, P = 0.49), based on clinic location. CONCLUSIONS: The use of telehealth did not negatively impact laboratory response to HU. Future studies should identify novel approaches to improve access to HU among patients with SCA living in rural areas.

Transcranial Doppler Screening in a Current Cohort of Children With Sickle Cell Anemia: Results From the DISPLACE Study.

Stroke prevention guidelines for sickle cell anemia (SCA) recommend transcranial Doppler (TCD) screening to identify children at stroke risk; however, TCD screening implementation remains poor. This report describes results from Part 1 of the 28-site DISPLACE (Dissemination and Implementation of Stroke Prevention Looking at the Care Environment) study, a baseline assessment of TCD implementation rates. This report describes TCD implementation by consortium site characteristics; characteristics of TCDs completed; and TCD results based on age. The cohort included 5247 children with SCA, of whom 5116 were eligible for TCD implementation assessment for at least 1 study year. The majority of children were African American or Black, non-Hispanic and received Medicaid. Mean age at first recorded TCD was 5.9 and 10.5 years at study end. Observed TCD screening rates were unsatisfactory across geographic regions (mean 49.9%; range: 30.9% to 74.7%) independent of size, institution type, or previous stroke prevention trial participation. The abnormal TCD rate was 2.9%, with a median age of 6.3 years for first abnormal TCD result. Findings highlight real-world TCD screening practices and results from the largest SCA cohort to date. Data informed the part 3 implementation study for improving stroke screening and findings may inform clinical practice improvements.

Outpatient pain clinic and intranasal fentanyl to improve sickle cell disease outcomes.

BACKGROUND: Acute pain events are a leading complication for sickle cell patients. In an attempt to improve pain outcomes, we developed an outpatient pain clinic, and included intranasal fentanyl in the opioid emergency department (ED) pain order set. We evaluated admission rates and opioid administration for patients that attended both the outpatient pain clinic and ED within a 3-month period. METHODS: We recorded the admission rate, IV morphine equivalents, and time from triage for each opioid order and administration from both an outpatient pain clinic and ED visit within a 3-month period for an individual pediatric patient with sickle cell disease. RESULTS: Thirty patients received acute pain management in both settings. We identified a significant reduction in hospital admission when patients received care in the pain clinic as compared to the ED (17% vs 43%, P = .02). Additionally, outpatient pain clinic patients received significantly less IV morphine equivalents than patients received in the ED (5.6 vs 10.6 IV morphine equivalents, P < .0001). In the ED, intranasal fentanyl was administered in a significantly shorter time than patients ordered intravenous opioid (43 vs 75 min, P = .02). The mean time to receiving an opioid in the outpatient pain clinic was 57 min. CONCLUSION: The use of an outpatient pain clinic can reduce admission rates as compared to the ED. The use of intranasal fentanyl reduced the time to first opioid administration in the ED. Patient-centered research or quality improvement projects should continue to focus on novel approaches to acute pain event management.

Hyperfiltration during early childhood precedes albuminuria in pediatric sickle cell nephropathy.

BACKGROUND: In patients with diabetes mellitus, hyperfiltration precedes the development of albuminuria. Pediatric sickle cell anemia (SCA) patients have a high prevalence of hyperfiltration and albuminuria during early childhood and adolescence. We tested the hypothesis that hyperfiltration precedes the development of albuminuria in a longitudinal pediatric SCA cohort. METHODS: We identified 91 participants with HbSS or SB0 thalassemia 5-21 years of age enrolled in a longitudinal sickle cell nephropathy cohort study who had a cystatin C measured during early childhood (4-10 years of age). Early hyperfiltration was defined as a mean eGFR >180 mL/min/1.73m2 using cystatin C obtained from 4 to 10 years of age. Persistent albuminuria was defined as an albumin to creatinine ratio > 30 mg/g on two of three untimed urine specimens. Time to event analysis estimated survival curves for participants with and without hyperfiltration using Kaplan-Meier curves and used logrank test for categorical variables to assess the association with time to development of the first episode persistent albuminuria. RESULTS: Persistent albuminuria occurred more often and at an earlier age in participants with early hyperfiltration compared to those without early hyperfiltration (log-rank, P = .004). Participants who developed albuminuria have a significant increase in their eGFR during childhood (P = .003) as compared to participants who have not yet progressed to albuminuria (P = .26). For every 1 g/dL increase in hemoglobin, the hazard ratio for developing persistent proteinuria decreased by 0.56 (95% CI: 0.3, 1.06, P = .07). CONCLUSION: Hyperfiltration precedes the development of persistent proteinuria in pediatric SCA patients. Intervention strategies should target lowering eGFR during early childhood.

The phenotypic spectrum of germline YARS2 variants: from isolated sideroblastic anemia to mitochondrial myopathy, lactic acidosis and sideroblastic anemia 2.

YARS2 variants have previously been described in patients with myopathy, lactic acidosis and sideroblastic anemia 2 (MLASA2). YARS2 encodes the mitochondrial tyrosyl-tRNA synthetase, which is responsible for conjugating tyrosine to its cognate mt-tRNA for mitochondrial protein synthesis. Here we describe 14 individuals from 11 families presenting with sideroblastic anemia and YARS2 variants that we identified using a sideroblastic anemia gene panel or exome sequencing. The phenotype of these patients ranged from MLASA to isolated congenital sideroblastic anemia. As in previous cases, inter- and intra-familial phenotypic variability was observed, however, this report includes the first cases with isolated sideroblastic anemia and patients with biallelic YARS2 variants that have no clinically ascertainable phenotype. We identified ten novel YARS2 variants and three previously reported variants. In vitro amino-acylation assays of five novel missense variants showed that three had less effect on the catalytic activity of YARS2 than the most commonly reported variant, p.(Phe52Leu), associated with MLASA2, which may explain the milder phenotypes in patients with these variants. However, the other two missense variants had a more severe effect on YARS2 catalytic efficiency. Several patients carried the common YARS2 c.572 G>T, p.(Gly191Val) variant (minor allele frequency =0.1259) in trans with a rare deleterious YARS2 variant. We have previously shown that the p.(Gly191Val) variant reduces YARS2 catalytic activity. Consequently, we suggest that biallelic YARS2 variants, including severe loss-of-function alleles in trans of the common p.(Gly191Val) variant, should be considered as a cause of isolated congenital sideroblastic anemia, as well as the MLASA syndromic phenotype.

Management of severe chronic pain with methadone in pediatric patients with sickle cell disease.

Vasocclusive pain crises are common among pediatric patients with sickle cell disease (SCD). Some patients with repeated pain crises develop chronic pain. We performed a retrospective cohort study of pediatric patients with SCD with chronic pain treated with methadone. We identified a significant reduction in pain hospitalizations following methadone treatment (0.35 ± 0.19 vs. 0.19 ± 0.17 hospitalizations/month, P = 0.016). In addition, we did not observe overt organ toxicity nor symptoms of opioid withdrawal during methadone wean. We suggest that methadone is safe and has some clinical benefit, which should be proven in prospective randomized trials for pediatric patients with SCD and chronic pain.

Outcomes of febrile events in pediatric patients with sickle cell anemia.

BACKGROUND: Limited evidence exists to create institutional admission criteria guidelines for febrile sickle cell patients. In addition, evidence is lacking to understand readmission rates for febrile sickle cell patients discharged from the emergency department (ED) or hospital. PROCEDURES: We conducted a 16-year retrospective study of bacteremia outcomes for febrile sickle cell patients. Risk variables analyzed included fever (either ≥ 39.5°C or ≥40°C), abnormal white blood cell (WBC) (>30,000 or <5,000/mcL), tachycardia and hypotension, or "ill appearing." Fourteen-day readmission rates were analyzed to determine outcomes for febrile sickle cell patients discharged from the ED or discharged within 72 h. RESULTS: Bacteremia was identified in 17 (2.6%) of 653 febrile events that are presented to the ED. "Ill-appearing" patients had an 8.5-fold increased odds of being diagnosed with bacteremia. Models using WBC count, "ill appearing," and hypotension have the highest sensitivity and specificity (AUC > 0.75). Among 427 patients discharged from the ED or within 72 h of hospitalization, only 10 (2.3%) were readmitted for a new sickle cell complication. CONCLUSIONS: Institutions can develop admission criteria based on WBC count, hypotension, and "ill appearance." Persistently febrile, well-appearing patient can be discharged at 48 h with minimal risk for new complications.

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.

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.

Hydroxycarbamide versus chronic transfusion for maintenance of transcranial doppler flow velocities in children with sickle cell anaemia-TCD With Transfusions Changing to Hydroxyurea (TWiTCH): a multicentre, open-label, phase 3, non-inferiority trial.

BACKGROUND: For children with sickle cell anaemia and high transcranial doppler (TCD) flow velocities, regular blood transfusions can effectively prevent primary stroke, but must be continued indefinitely. The efficacy of hydroxycarbamide (hydroxyurea) in this setting is unknown; we performed the TWiTCH trial to compare hydroxyurea with standard transfusions. METHODS: TWiTCH was a multicentre, phase 3, randomised, open-label, non-inferiority trial done at 26 paediatric hospitals and health centres in the USA and Canada. We enrolled children with sickle cell anaemia who were aged 4-16 years and had abnormal TCD flow velocities (≥ 200 cm/s) but no severe vasculopathy. After screening, eligible participants were randomly assigned 1:1 to continue standard transfusions (standard group) or hydroxycarbamide (alternative group). Randomisation was done at a central site, stratified by site with a block size of four, and an adaptive randomisation scheme was used to balance the covariates of baseline age and TCD velocity. The study was open-label, but TCD examinations were read centrally by observers masked to treatment assignment and previous TCD results. Participants assigned to standard treatment continued to receive monthly transfusions to maintain 30% sickle haemoglobin or lower, while those assigned to the alternative treatment started oral hydroxycarbamide at 20 mg/kg per day, which was escalated to each participant's maximum tolerated dose. The treatment period lasted 24 months from randomisation. The primary study endpoint was the 24 month TCD velocity calculated from a general linear mixed model, with the non-inferiority margin set at 15 cm/s. The primary analysis was done in the intention-to-treat population and safety was assessed in all patients who received at least one dose of assigned treatment. This study is registered with ClinicalTrials.gov, number NCT01425307. FINDINGS: Between Sept 20, 2011, and April 17, 2013, 159 patients consented and enrolled in TWiTCH. 121 participants passed screening and were then randomly assigned to treatment (61 to transfusions and 60 to hydroxycarbamide). At the first scheduled interim analysis, non-inferiority was shown and the sponsor terminated the study. Final model-based TCD velocities were 143 cm/s (95% CI 140-146) in children who received standard transfusions and 138 cm/s (135-142) in those who received hydroxycarbamide, with a difference of 4·54 (0·10-8·98). Non-inferiority (p=8·82 × 10(-16)) and post-hoc superiority (p=0·023) were met. Of 29 new neurological events adjudicated centrally by masked reviewers, no strokes were identified, but three transient ischaemic attacks occurred in each group. Magnetic resonance brain imaging and angiography (MRI and MRA) at exit showed no new cerebral infarcts in either treatment group, but worsened vasculopathy in one participant who received standard transfusions. 23 severe adverse events in nine (15%) patients were reported for hydroxycarbamide and ten serious adverse events in six (10%) patients were reported for standard transfusions. The most common serious adverse event in both groups was vaso-occlusive pain (11 events in five [8%] patients with hydroxycarbamide and three events in one [2%] patient for transfusions). INTERPRETATION: For high-risk children with sickle cell anaemia and abnormal TCD velocities who have received at least 1 year of transfusions, and have no MRA-defined severe vasculopathy, hydroxycarbamide treatment can substitute for chronic transfusions to maintain TCD velocities and help to prevent primary stroke. FUNDING: National Heart, Lung, and Blood Institute, National Institutes of Health.

Acute kidney injury during a pediatric sickle cell vaso-occlusive pain crisis.

BACKGROUND: Patients who develop sickle cell disease (SCD) nephropathy are at a high risk for mortality. The pathophysiology of vaso-occlusive pain crisis may contribute to acute kidney injury (AKI). Non-steroidal anti-inflammatory drugs, known inducers of AKI, are used to treat pain crises. Multiple gaps exist in the knowledge about the impact of AKI in SCD. METHODS: We conducted a 2-year retrospective review of AKI events in patients admitted for vaso-occlusive crisis. AKI was defined by an increase of ≥0.3 mg/dL or 50% in serum creatinine from baseline. Laboratory values and ketorolac administration by days and dose (mg/kg) were identified from hospital records. A generalized mixed effects model for binary outcomes evaluated AKI based on laboratory variables and ketorolac administration. A generalized mixed Poisson effects model analyzed the association of AKI with hospital length of stay. RESULTS: Thirty-three out of 197 admissions for vaso-occlusive pain crisis (17%) were associated with AKI. Fifty-two percent of the cases presented to the Emergency Room (ER) with AKI. Every one unit decrease in hemoglobin from baseline to admission increased the risk of AKI by 49%. Among patients who received ketorolac for pain, both total days and doses of ketorolac were associated with AKI. Finally, patients with pain and AKI required longer periods of hospitalization than patients without AKI. CONCLUSION: Acute kidney injury during sickle cell pain crisis is common and may be an important modifiable risk factor for developing chronic kidney disease (CKD). Further studies are needed to determine the impact of nephrotoxic medications on progressive SCD nephropathy.

Effects of hydroxyurea treatment for patients with hemoglobin SC disease.

Although hemoglobin SC (HbSC) disease is usually considered less severe than sickle cell anemia (SCA), which includes HbSS and HbS/ß(0) -thalassemia genotypes, many patients with HbSC experience severe disease complications, including vaso-occlusive pain, acute chest syndrome, avascular necrosis, retinopathy, and poor quality of life. Fully 20 years after the clinical and laboratory efficacy of hydroxyurea was proven in adult SCA patients, the safety and utility of hydroxyurea treatment for HbSC patients remain unclear. Recent NHLBI evidence-based guidelines highlight this as a critical knowledge gap, noting HbSC accounts for ∼30% of sickle cell patients within the United States. To date, only 5 publications have reported short-term, incomplete, or conflicting laboratory and clinical outcomes of hydroxyurea treatment in a total of 71 adults and children with HbSC. We now report on a cohort of 133 adult and pediatric HbSC patients who received hydroxyurea, typically for recurrent vaso-occlusive pain. Hydroxyurea treatment was associated with a stable hemoglobin concentration; increased fetal hemoglobin (HbF) and mean corpuscular volume (MCV); and reduced white blood cell count (WBC), absolute neutrophil count (ANC), and absolute reticulocyte count (ARC). Reversible cytopenias occurred in 22% of patients, primarily neutropenia and thrombocytopenia. Painful events were reduced with hydroxyurea, more in patients >15 years old. These multicenter data support the safety and potentially salutary effects of hydroxyurea treatment for HbSC disease; however, a multicenter, placebo-controlled, Phase 3 clinical trial is needed to determine if hydroxyurea therapy has efficacy for patients with HbSC disease.

Patient-centered approach to designing sickle cell transition education.

INTRODUCTION: It is vital to engage patients with sickle cell disease (SCD) in the transition process from pediatric to adult care. To better understand the patient perspective during the time of transition, we conducted this research with the goal of incorporating patient comprehension and desires for transition education. MATERIALS AND METHODS: We surveyed 37 adolescent patients with SCD about their understanding of SCD and transition education preferences. In addition, patient responses were analyzed to understand differences among urban and rural patients. RESULTS: The mean age of surveyed participants was 14.9 years (SD=2.1). Forty-three percent of participants responded that the topic of transition had been introduced to them, and only 21% responded that they received education about transition. Despite the poor awareness about transition, almost all participants were interested in learning more about the transition process through a technology-based transition education platform where individual health topics could be explored. DISCUSSION: Despite a didactic teaching approach to transition education, we identified that sickle cell participants had poor recognition of receiving transition education and poor understanding of their basic medical history. However, patients can identify specific health topics that should be addressed during an individualized transition education program.

Systematic review of interventional sickle cell trials registered in ClinicalTrials.gov.

BACKGROUND/AIMS: The registry ClinicalTrials.gov was created to provide investigators and patients an accessible database of relevant clinical trials. METHODS: To understand the state of sickle cell disease clinical trials, a comprehensive review of all 174 "closed," "interventional" sickle cell trials registered at ClinicalTrials.gov was completed in January 2015. RESULTS: The majority of registered sickle cell disease clinical trials listed an academic center as the primary sponsor and were an early phase trial. The primary outcome for sickle cell disease trials focused on pain (23%), bone marrow transplant (BMT) (13%), hydroxyurea (8%), iron overload (8%), and pulmonary hypertension (8%). A total of 52 trials were listed as terminated or withdrawn, including 25 (14% of all trials) terminated for failure to enroll participants. At the time of this review, only 19 trials uploaded results and 29 trials uploaded a manuscript in the ClinicalTrials.gov database. A systematic review of pubmed.gov revealed that only 35% of sickle cell studies completed prior to 2014 resulted in an identified manuscript. In comparison, of 80 thalassemia trials registered in ClinicalTrials.gov, four acknowledged failure to enroll participants as a reason for trial termination or withdrawal, and 48 trials (60%) completed prior to 2014 resulted in a currently identified manuscript. CONCLUSION: ClinicalTrials.gov can be an important database for investigators and patients with sickle cell disease to understand the current available research trials. To enhance the validity of the website, investigators must update their trial results and upload trial manuscripts into the database. This study, for the first time, quantifies outcomes of sickle cell disease trials and provides support to the belief that barriers exist to successful completion, publication, and dissemination of sickle cell trial results.

Ferritin and LIC: predicting liver injury in children with sickle cell.

OBJECTIVE: Chronic blood transfusion therapy reduces clinical events in children with sickle cell anemia but increases risk for an iron-related liver injury. Liver biopsy is the gold standard technique for quantifying liver iron content (LIC) and evaluating liver pathology. Ferritin, liver enzymes, and R2* magnetic resonance imaging of the liver are obtained as surrogate markers. In this study we compared surrogate markers with the gold standard, liver biopsy, in assessing liver histology. METHODS: We conducted a retrospective review of 259 liver biopsies in 109 children with sickle cell anemia on chronic transfusion therapy and chelation therapy during a 9-year period at a single center. Liver pathology was compared with LIC, ferritin, and alanine aminotransferase. RESULTS: Ferritin correlates with LIC (r = 0.74, P < 0.001), although there is a broad range of ferritin values for a given LIC. Furthermore, patients with a high LIC (≥7 mg Fe/g dry weight) demonstrated significantly higher ferritin as compared to the patients with lower LIC <7 (P < 0.001). Periportal/portal inflammation also showed a significant relation. There was no significance when comparing ferritin and lobular inflammation or ferritin and alanine aminotransferase. When evaluating LIC in relation to fibrosis, the present study revealed that there was only a significant correlation with severe fibrosis (F = 36, P < 0.001). CONCLUSIONS: The results suggest that although correlations exist among ferritin and LIC and severe fibrosis and LIC, caution should be taken when they are used in isolation. Liver biopsy provides important pathologic information that cannot be obtained through surrogate markers.

Effects of chronic transfusions on abdominal sonographic abnormalities in children with sickle cell anemia.

OBJECTIVE: To assess the effects of chronic erythrocyte transfusions on prevalence of sonographic incidence of organ damage in children with sickle cell anemia (SCA). STUDY DESIGN: Children (N=148; mean age, 13.0 years) with SCA, receiving chronic transfusions (average, 7 years), underwent abdominal sonography at 25 institutions. After central imaging review, spleen, liver, and kidney measurements were compared with published normal values. Potential relations between ultrasound, clinical, and laboratory data were explored via analysis of variance, Student t test, and Cochran-Mantel-Haenzel tests of non-zero correlation. RESULTS: Average spleen length was similar to normal children, but over one-third had spleen volumes >300 mL, 15 had previous splenectomy for splenomegaly, and 24 had abnormal splenic echotexture. Two-thirds had hepatobiliary disease; 37 had prior cholecystectomy, 46 had gallstones, and 16 had gallbladder sludge. Gallbladder disease correlated with older age (P=.002), longer liver length (P<.001), longer duration of transfusions (P=.034), and higher total bilirubin (P<.001). Liver (P<.001) and renal lengths (P≤.005) were larger than published norms. CONCLUSIONS: In children with SCA, long-term transfusion therapy may not prevent development or progression of abdominal organ dysfunction.