Survival of children with sickle cell disease

High Healthcare Utilization in Adolescents with Sickle Cell Disease Prior to Transition to Adult Care: A Retrospective Study

BACKGROUND

The transition from pediatric to adult care in the US is often difficult for individuals with sickle cell disease (SCD). Young adults (18 to 25 years of age) have higher acute care utilization and an increased risk of poor outcomes. The current study was designed to provide greater insights into patients (16 to 18 years of age) with SCD prior to their transition to adult care.

OBJECTIVES

To describe current treatment patterns, pain crises prevalence, SCD-related complications, and healthcare resource utilization (HCRU) in 16-to-18-year-old patients with SCD.

METHODS

From 1/1/2015-6/30/2017 using MarketScan Databases, patients were included if they were 16 to 18 years old at the index date, had ≥1 inpatient or 2 outpatient SCD diagnosis claims during the identification period, and were continuously enrolled in the database for at least one year prior (baseline) and post index date. Outcomes included medications, disease management interventions, Charlson Comorbidity Index (CCI), vaso-occlusive (VOC) crises requiring healthcare visits, HCRU, and SCD complications.

RESULTS

1,186 patients were included; most (64.3%) were female. The mean CCI was 1.3 (SD: 0.7). In the overall cohort, patients experienced an average of 3.9 (SD: 4.2) VOCs and most patients (61.1%, n=725) had chronic complications during the one-year follow-up. Pulmonary disease (31.1%, n=369) was the most frequent complication; blood transfusions (mean: 8.4 [SD:7.0]) and iron-chelating therapies (mean: 8.6 [SD:10]) were the most common interventions and medications, respectively. In the 16 to 18 year old group, patients with SCD had 2.0 (SD = 2.3) hospital admissions, 3.4 (SD = 4.0) ER visits, and 5.0 (SD = 4.2) office visits.

CONCLUSIONS

Prior to transition to adult care, adolescents with SCD already have significant a cute and chronic disease-related complications, possibly contributing to frequent healthcare visits. Increased attention to this age group, including improvements in disease modifying therapy, are needed prior to transition to adult care systems to improve outcomes.

Point-of-care screening for sickle cell disease in low-resource settings: A multi-center evaluation of HemoTypeSC, a novel rapid test

Sickle cell disease (SCD) is a common, life-threatening genetic disorder that is best managed when diagnosed early by newborn screening. However, SCD is most prevalent in low-resource regions of the world where newborn screening is rare and diagnosis at the point-of-care is challenging. In many such regions, the majority of affected children die, undiagnosed, before the age of 5 years. A rapid and affordable point-of-care test for SCD is needed. The diagnostic accuracy of HemoTypeSC, a point-of-care immunoassay, for SCD was evaluated in individuals who had SCD, hemoglobin C disease, the related carrier (trait) states, or a normal hemoglobin phenotype. Children and adults participated in low-, medium- and high-resource environments (Ghana [n = 383], Martinique [n = 46], and USA [n = 158]). Paired blood specimens were obtained for HemoTypeSC and a reference diagnostic assay. HemoTypeSC testing was performed at the site of blood collection, and the reference test was performed in a laboratory at each site. In 587 participants, across all study sites, HemoTypeSC had an overall sensitivity of 99.5% and specificity of 99.9% across all hemoglobin phenotypes. The test had 100% sensitivity and specificity for sickle cell anemia. Sensitivity and specificity for detection of normal and trait states were >99%. HemoTypeSC is an inexpensive (<$2 per test), accurate, and rapid point-of-care test that can be used in resource-limited regions with a high prevalence of SCD to provide timely diagnosis and support newborn screening programs.

Hearing loss in children with sickle cell disease: A prospective French cohort study

BACKGROUND

Sickle cell disease (SCD) is the most common genetic disease in France. In developing countries, it is associated with a high incidence of hearing loss. The aim of this study was to determine the prevalence of hearing loss in French children with SCD in order to determine if they need a close audiological follow-up.

METHODS

We performed a single-center prospective cross-sectional study of children with SCD. The children, without specific hearing symptom, underwent an ear, nose and throat examination with a hearing assessment between 2015 and 2016.

RESULTS

Eighty-nine children were included, aged from 5 to 19 years, with 73% of SS or Sβ⁰ genotype and 27% of SC or Sβ⁺ genotype. Ten children (11.2%) had hearing thresholds higher than 20 dB in at least one ear: one child with subnormal hearing, six otitis media with effusion (OME), and three sensorineural hearing loss. Late age at diagnosis of SCD, a high platelet count and a low hematocrit level were significantly associated with OME; moreover, children with OME had more severe clinical and biological characteristics than children with normal hearing. Furthermore, 12.4% of the children complained of tinnitus. The rate of sudden hearing loss was 2.2%. Finally, 7.1% of patients with normal hearing showed a speech discrimination disorder.

CONCLUSIONS

Several causes were identified for hearing loss in children with SCD. They therefore need a close audiological follow-up in order to avoid complications due to curable phenomena and to enable appropriate management for progressive complications.

Neonatal Screening for Sickle Cell Disease in Belgium for More than 20 Years: An Experience for Comprehensive Care Improvement

Our previous results reported that compared to sickle cell patients who were not screened at birth, those who benefited from it had a lower incidence of a first bacteremia and a reduced number and days of hospitalizations. In this context, this article reviews the Belgian experience on neonatal screening for sickle cell disease (SCD). It gives an update on the two regional neonatal screening programs for SCD in Belgium and their impact on initiatives to improve clinical care for sickle cell patients. Neonatal screening in Brussels and Liège Regions began in 1994 and 2002, respectively. Compiled results for the 2009 to 2017 period demonstrated a birth prevalence of sickle cell disorder above 1:2000. In parallel, to improve clinical care, (1) a committee of health care providers dedicated to non-malignant hematological diseases has been created within the Belgian Haematology Society; (2) a clinical registry was implemented in 2008 and has been updated in 2018; (3) a plan of action has been proposed to the Belgian national health authority. To date, neonatal screening is not integrated into the respective Belgian regional neonatal screening programs, the ongoing initiatives in Brussels and Liège Regions are not any further funded and better management of the disease through the implementation of specific actions is not yet perceived as a public health priority in Belgium.

Sickle Cell Clinical Research and Intervention Program (SCCRIP): A lifespan cohort study for sickle cell disease progression from the pediatric stage into adulthood

BACKGROUND

Previous natural history studies have advanced the understanding of sickle cell disease (SCD), but generally have not included sufficient lifespan data or investigation of the role of genetics in clinical outcomes, and have often occurred before the widespread use of disease-modifying therapies, such as hydroxyurea and chronic erythrocyte transfusions. To further advance knowledge of SCD, St. Jude Children's Research Hospital established the Sickle Cell Clinical Research and Intervention Program (SCCRIP), to conduct research in a clinically evaluated cohort of individuals with SCD across their lifetime.

PROCEDURES

Initiated in 2014, the SCCRIP study prospectively recruits patients diagnosed with SCD and includes retrospective and longitudinal collection of clinical, neurocognitive, geospatial, psychosocial, and health outcomes data. Biological samples are banked for future genomics and proteomics studies. The organizational structure of SCCRIP is based upon organ/system-specific working groups and is opened to the research community for partnerships.

RESULTS

As of August 2017, 1,044 (92.3% of eligible) patients with SCD have enrolled in the study (860 children and 184 adults), with 11,915 person-years of observation. Population demographics included mean age at last visit of 11.3 years (range 0.7-30.1), 49.8% females, 57.7% treated with hydroxyurea, 8.5% treated with monthly transfusions, and 62.9% hemoglobin (Hb) SS or HbSB⁰ -thalassemia, 25.7% HbSC, 8.4% HbsB⁺ -Thalassemia, 1.7% HbS/HPFH, and 1.2% other.

CONCLUSIONS

The SCCRIP cohort will provide a rich resource for the conduct of high impact multidisciplinary research in SCD.

Factors Associated With Mechanical Ventilation Use in Children With Sickle Cell Disease and Acute Chest Syndrome

OBJECTIVES

Acute chest syndrome is the leading cause of death in children with sickle cell disease and is generally due to respiratory failure. Epidemiologic factors for a need for mechanical ventilation in children with acute chest syndrome require further clarification.

DESIGN

Retrospective observational study.

SETTING

Nationally representative pediatric inpatient records in the United States by using the Kids' Inpatient Database for the years 2003, 2006, 2009, and 2012.

PATIENTS

Patients age less than 20 years old with a discharge diagnosis of acute chest syndrome.

MEASUREMENTS AND MARIN RESULTS

Data were weighted to estimate annual hospitalizations according to hospital characteristics in the United States. Multivariable logistic regression was conducted to ascertain factors associated with use of mechanical ventilation, after adjusting for patient and hospital characteristics. Total hospitalizations for acute chest syndrome were 5,018 in 2003, 6,058 in 2006, 6,072 in 2009, and 6,360 in 2012. Mechanical ventilation use was associated with comorbidities of obesity (odds ratio, 3.35; 95% CI, 1.94-5.78), obstructive sleep apnea (odds ratio, 3.72; 95% CI, 2.23-6.20), and heart disease (odds ratio, 2.19; 95% CI, 1.47-3.27). In addition, nonblack compared with black children (odds ratio, 1.53; 95% CI, 1.02-2.31) and the fall season (p = 0.018) were associated with mechanical ventilation use.

CONCLUSIONS

Comorbidity of obesity, obstructive sleep apnea, or heart disease could be potentially associated with mechanical ventilation use during an episode of acute chest syndrome. Prospective observational studies would be required to confirm these findings and infer potential interventions for preventing illness severity.

A Retrospective Analysis of Sociodemographic and Hematologic Characteristics Associated With Achieving Optimal Hydroxyurea Therapy in Children With Sickle Cell Disease

Hydroxyurea (HU) has proven hematologic and clinical benefits, especially when escalated to the maximum tolerated dose (MTD). We reviewed clinical data from patients with sickle cell disease (January 2011 to 2016) to determine baseline sociodemographic and laboratory parameters associated with reaching HU MTD without significant delays. In total, 210 patients (mean HU start age, 6.6 y) were included. Initial Kaplan-Meier event analysis showed 1 year to be an inflection point for reaching MTD. In total, 116 patients (55%) reached MTD in <1 year, with 56 (27%) taking >1 year to reach MTD and 38 (18%) patients not successfully reaching MTD during follow-up. In both crude and adjusted analyses, age at HU start was found to be significantly and inversely associated with reaching MTD within 1 year. The data presented, specifically the inflection point of reaching MTD at 1 year and the association of young HU start age with reaching MTD within a year, suggest that successful achievement of MTD may be facilitated by starting patients on HU at a young age and that older patients should receive additional intervention to attain MTD within 1 year. Patients who do not achieve MTD within a year may need the most extensive intervention.

Pneumococcal and Meningococcal Vaccination among Michigan Children with Sickle Cell Disease

OBJECTIVES

To determine the proportion of Michigan children with sickle cell disease (SCD) who were vaccinated according to pneumococcal vaccination recommendations and, secondarily, to examine uptake of meningococcal vaccine, and to compare up-to-date (UTD) vaccination status between children with and without SCD.

STUDY DESIGN

Children with SCD who were born in Michigan were matched to controls without SCD using age, sex, race, and zip code. Using data from the state immunization registry, we assessed the significance of SCD status on UTD vaccination in logistic regression models.

RESULTS

By 36 months, substantially more children with SCD had completed the pneumococcal conjugate vaccine series (68.8%) than children without SCD (45.2%), and 59% of children with SCD had received a meningococcal vaccine. Compared with children without SCD, children with SCD had higher odds of UTD pneumococcal status at 5, 7, and 16 months. However, a large proportion of children with SCD were missing key vaccination targets: of those who received a full 7-valent pneumococcal conjugate vaccine series, 29.1% had not received a 13-valent pneumococcal conjugate vaccine dose, and 21.8% had not had pneumococcal polysaccharide vaccine administered.

CONCLUSIONS

The pneumococcal and meningococcal vaccination schedules have become increasingly complex in recent years. Assessment algorithms programmed to forecast doses due based on high-risk conditions, such as SCD, could provide a useful reminder to healthcare providers in the context of increasingly complex and changing recommendations.

Sickle cell disease

Sickle cell disease (SCD) is a group of inherited disorders caused by mutations in HBB, which encodes haemoglobin subunit β. The incidence is estimated to be between 300,000 and 400,000 neonates globally each year, the majority in sub-Saharan Africa. Haemoglobin molecules that include mutant sickle β-globin subunits can polymerize; erythrocytes that contain mostly haemoglobin polymers assume a sickled form and are prone to haemolysis. Other pathophysiological mechanisms that contribute to the SCD phenotype are vaso-occlusion and activation of the immune system. SCD is characterized by a remarkable phenotypic complexity. Common acute complications are acute pain events, acute chest syndrome and stroke; chronic complications (including chronic kidney disease) can damage all organs. Hydroxycarbamide, blood transfusions and haematopoietic stem cell transplantation can reduce the severity of the disease. Early diagnosis is crucial to improve survival, and universal newborn screening programmes have been implemented in some countries but are challenging in low-income, high-burden settings.

Early initiation of inhaled corticosteroids does not decrease acute chest syndrome morbidity in pediatric patients with sickle cell disease

Acute chest syndrome (ACS) is a leading cause of mortality in patients with sickle cell disease (SCD). Systemic corticosteroids decrease ACS severity, but the risk of readmission for vaso-occlusive crises (VOC) has limited their use. The efficacy of inhaled corticosteroids (ICS) as a safer alternative is currently unknown. An observational, historic cohort study compared patients with SCD with ACS who received ICS at admission (ICS) to those who did not (non-ICS). Outcome measures included rates of transfusion, oxygen requirement, BiPAP initiation, PICU transfer, intubation, readmission, hospital cost, and length of stay. One hundred twenty patients with SCD (55 non-ICS, 65 ICS) were included. A significantly higher proportion of the non-ICS group had bilateral infiltrates, but fewer had asthma. More children in the ICS group had BiPAP initiated, however transfer to the PICU, intubation, transfusion rates, oxygen requirement, hospital cost, length of stay, and readmission rates did not differ between groups. Regression analysis did not reveal any differences in outcomes, nor were outcomes changed when patients were separated based on the presence or absence of asthma. In this observational cohort study, ICS did not demonstrate a significant reduction in ACS morbidity, though ICS use should be studied in a prospective manner.

Mortality in children, adolescents and adults with sickle cell anemia in Rio de Janeiro, Brazil

OBJECTIVE

To determine the mortality rate of children, adolescents and adults with sickle cell anemia in Rio de Janeiro, Brazil.

METHODS

The number of deaths, the mortality rate and the causes of deaths in patients with sickle cell anemia who were treated and followed up at our institution for 15 years were determined and compared to data available for the Brazilian population.

RESULTS

The overall number of deaths was 281 patients with a mortality rate of 16.77%. Survival probability was significantly higher in females. The number of deaths and the mortality rate were age-specific with a significant increase in the 19- to 29-year-old age group. The remaining life expectancy of the patients with sickle cell anemia was less than that of Brazilians at large. The gap between the two was about 20 years for ages between one and five years with this gap decreasing to ten years after the age of 65 years. The most common causes of death were infection, acute chest syndrome, overt stroke, organ damage and sudden death during painful crises.

CONCLUSION

To the best of our knowledge, this is the first Brazilian study in a single institution in Rio de Janeiro; the mortality rate was 18.87% among adult patients with sickle cell anemia. The mortality rates in children and adults are higher than those reported in developed countries of the northern hemisphere.

Serum Soluble Transferrin Receptor Concentrations Are Elevated in Congolese Children with Glucose-6-Phosphate Dehydrogenase Variants, but Not Sickle Cell Variants or α-Thalassemia

Background: Anemia is common in Congolese children, and inherited blood disorders may be a contributing cause. The presence of sickle cell variants, X-linked glucose-6-phosphate dehydrogenase (G6PD) deficiency and α-thalassemia, has been previously reported. G6PD A- deficiency is characterized by the co-inheritance of G6PD 376 and 202 variants and is common in sub-Saharan Africa.Objective: We aimed to measure the associations between inherited blood disorders and hemoglobin, ferritin, and soluble transferrin receptor (sTfR) concentrations in Congolese children.Methods: Venous blood was collected from 744 children aged 6-59 mo from 2 provinces. We measured biomarkers of nutritional and inflammation status and malaria. Pyrosequencing was used to detect sickle cell variants. Polymerase chain reaction was used to detect G6PD variants and α-thalassemia deletions.Results: Overall, 11% of children had a sickle cell variant, 19% of boys were G6PD A- hemizygotes, 12% and 10% of girls were G6PD A- hetero- or homozygotes, respectively, and 12% of children had α-thalassemia. Multivariable linear regression models (adjusted for age, province, altitude, malaria, and biomarkers of nutritional and inflammation status) showed that G6PD A- hemizygous boys and G6PD 376 homozygous girls had higher sTfR concentrations [geometric mean ratios (95% CIs): 1.20 (1.03, 1.39) and 1.25 (1.02, 1.53), respectively] than children with no G6PD variants. Hemoglobin and ferritin concentrations were not independently associated with any of the inherited blood disorder genotypes.Conclusions: We found that 2 G6PD variant genotypes were associated with elevated sTfR concentrations, which limits the accuracy of sTfR as a biomarker of iron status in this population.

The effects of music therapy on transition outcomes in adolescents and young adults with sickle cell disease

Background The Build, Educate, Advance, Transition, in Sickle cell disease (BEATS) music therapy program was developed to address health challenges faced by adolescents/young adults (AYA) with sickle cell disease (SCD) during the transition to adult medical care. Objective The purpose of this study was to investigate the effects of BEATS on self-efficacy, trust, knowledge about SCD, and adherence in adolescents/young adults (AYA) with SCD. Subjects Thirty AYA with SCD, 18-23 years old, recruited from an adult SCD clinic agreed to participate in four BEATS sessions over 1 year. Methods Self-efficacy, trust and SCD knowledge were measured prospectively at baseline and months 3, 6, 9, and 12. Adherence to clinic appointments and healthcare utilization were measured retrospectively from medical records. A repeated measures linear mixed-effect model with compound symmetry covariance structure was used to fit the data. Results BEATS participants demonstrated a significant improvement in SCD knowledge (p = 0.0002) compared to baseline, an increase in acute care clinic, but not emergency department, utilization (p = 0.0056), and a non-significant improvement in clinic attendance (p = 0.1933). Participants' subjective evaluations revealed a positive response to BEATS. There were no significant changes in self-efficacy, trust, hospital admissions, or blood transfusion adherence. Conclusion Culturally tailored, developmentally appropriate music therapy transition interventions can concretely improve SCD knowledge and may improve transition for AYA with SCD.

Neonatal screening improves sickle cell disease clinical outcome in Belgium

Objectives

To compare the outcomes of sickle cell disease patients diagnosed through neonatal screening with those who were not.

Methods

In an observational multicenter study in Belgium, 167 screened and 93 unscreened sickle cell disease patients were analyzed for a total of 1116 and 958 patient-years of follow-up, respectively. Both groups were compared with propensity score analysis, with patients matched on three covariates (gender, genotype, and central Africa origin). Bonferroni correction was applied for all comparisons.

Results

Kaplan–Meier estimates of survival without bacteremia were significantly higher in the screened group than the unscreened group (94.47%; [95% CI, 88.64–97.36%] versus 83.78% [95% CI, 72.27–90.42%]), p = 0.032. Non-significant differences between both groups were reported for survival without acute chest syndrome, acute anemia, cerebral complication, severe infection, and vaso-occlusive crisis. Significantly lower hospitalization rate and days per 100 patient-years were observed in the screened compared with the unscreened group (0.27 vs. 0.63 and 1.25 vs. 2.82, p = 0.0006 and <0.0001).

Conclusion

These data confirm the benefit of a neonatal screening programme in reducing bacteremia and hospitalization.

National registry of hemoglobinopathies in Spain (REPHem)

BACKGROUND

Although highly prevalent throughout the world, the accurate prevalence of hemoglobinopathies in Spain is unknown.

PROCEDURE

This study presents data on the national registry of hemoglobinopathies of patients with thalassemia major (TM), thalassemia intermedia (TI), and sickle cell disease (SCD) in Spain created in 2014. Fifty centers reported cases retrospectively. Data were registered from neonatal screening or from the first contact at diagnosis until last follow-up or death.

RESULTS

Data of the 715 eligible patients were collected: 615 SCD (497 SS, 64 SC, 54 SBeta phenotypes), 73 thalassemia, 9 CC phenotype, and 18 other variants. Most of the SCD patients were born in Spain (65%), and 51% of these were diagnosed at newborn screening. Median age at the first diagnosis was 0.4 years for thalassemia and 1.0 years for SCD. The estimated incidence was 0.002 thalassemia cases and 0.03 SCD cases/1,000 live births. Median age was 8.9 years (0.2-33.7) for thalassemia and 8.1 years (0.2-32.8) for SCD patients. Stroke was registered in 16 SCD cases. Transplantation was performed in 43 TM and 23 SCD patients at a median age of 5.2 and 7.8 years, respectively. Twenty-one patients died (3 TM, 17 SCD, 1 CC) and 200 were lost to follow-up. Causes of death were related to transplantation in three patients with TM and three patients with SCD. Death did not seem to be associated with SCD in six patients, but nine patients died secondary to disease complications. Overall survival was 95% at 15 years of age.

CONCLUSIONS

The registry provides data about the prevalence of hemoglobinopathies in Spain and will permit future cohort studies and the possibility of comparison with other registries.

Prevalence and Etiology of Bacteremia in Febrile Children with Sickle Cell Disease at a Nigeria Tertiary Hospital

Background & Objectives

As a result of immune defects in Sickle cell disease (SCD), affected individuals are prone to infection from encapsulated bacterial pathogens like Streptococcus Pneumoniae. Studies on the etiological agents of bacteremia in children with SCD in Nigeria are few and have revealed a spectrum of organisms that is different from those recorded in other parts of the world.

Aim and Objectives

The objectives of this study were to determine the prevalence of bacteremia, etiological agents and antibiotic susceptibility pattern in febrile children with SCD attending the University College Hospital (UCH), Ibadan, Nigeria.

Methods

The study was cross-sectional and took place at the Department of Pediatrics of the UCH, Ibadan. Children with SCD, ages 0–17 years presenting with axillary temperature ≥ 38°C were enrolled after obtaining informed consent. History was obtained and complete physical examination performed after which blood was collected for culture and antibacterial susceptibility tests.

Results

A total of 116 children were studied of which 69 (59.5%) were males, 111 (95.7%) were of the Hemoglobin SS phenotype and 5 (4.3%) of the Hemoglobin SC phenotype. Bacteremia was present in 16 (13.8%) of the 116 children. Gram negative bacteria constituted 10 (62.5%) of all isolates, while the predominant isolates were Klebsiella pneumoniae 4, (25%) and Staphylococcus aureus, 4 (25%). Over 80% of the isolates were susceptible to Ceftriaxone, Amikacin and Meropenem.

Conclusions

Klebsiella pneumoniae and Staphylococcus aureus are the predominant causes of bacteremia in children with SCD in Ibadan, contrary to findings in western countries.

Perioperative considerations for patients with sickle cell disease: a narrative review

PURPOSE

Approximately 200,000 individuals worldwide are born annually with sickle cell disease (SCD). Regions with the highest rates of SCD include Africa, the Mediterranean, and Asia, where its prevalence is estimated to be 2-6% of the population. An estimated 70,000-100,000 people in the United States have SCD. Due to enhanced newborn screening, a better understanding of this disease, and more aggressive therapy, many sickle cell patients survive into their adult years and present more frequently for surgery.

SOURCE

The authors identified relevant medical literature by searching PubMed, MEDLINE®, EMBASE™, Scopus™, Web of Science, and Google Scholar databases for English language publications appearing from 1972-September 2016. Case reports, abstracts, review articles, and original research articles were reviewed-with particular focus on the pathophysiology and medical management of SCD and any anesthesia-related issues.

PRINCIPAL FINDINGS

Perioperative physicians should be familiar with the triggers of a sickle cell crisis and vaso-occlusive disease. Sickle cell disease affects various organ systems, including the central nervous, cardiovascular, pulmonary, genitourinary, and musculoskeletal systems. Preoperative assessment should focus on end-organ dysfunction. Controversy continues regarding if and when sickle cell patients should receive transfusions and which anesthetic technique (regional or general) confers any benefits. Timely, appropriate, and sufficient analgesia is critical, especially when patients experience a vaso-occlusive crisis, acute chest syndrome, or acute postoperative pain.

CONCLUSION

Effective management of SCD patients in the perioperative setting requires familiarity with the epidemiology, pathophysiology, clinical manifestations, and treatment of SCD.

A Paper-Based Test for Screening Newborns for Sickle Cell Disease

The high cost, complexity and reliance on electricity, specialized equipment and supplies associated with conventional diagnostic methods limit the scope and sustainability of newborn screening for sickle cell disease (SCD) in sub-Saharan Africa and other resource-limited areas worldwide. Here we describe the development of a simple, low-cost, rapid, equipment- and electricity-free paper-based test capable of detecting sickle hemoglobin (HbS) in newborn blood samples with a limit of detection of 2% HbS. We validated this newborn paper-based test in a cohort of 159 newborns at an obstetric hospital in Cabinda, Angola. Newborn screening results using the paper-based test were compared to conventional isoelectric focusing (IEF). The test detected the presence of HbS with 81.8% sensitivity and 83.3% specificity, and identified SCD newborns with 100.0% sensitivity and 70.7% specificity. The use of the paper-based test in a two-stage newborn screening process could have excluded about 70% of all newborns from expensive confirmatory testing by IEF, without missing any of the SCD newborns in the studied cohort. This study demonstrates the potential utility of the newborn paper-based test for reducing the overall cost of screening newborns for SCD and thus increasing the practicality of universal newborn SCD screening programs in resource-limited settings.

Nasopharyngeal and Oropharyngeal Colonization by Staphylococcus aureus and Streptococcus pneumoniae and Prognostic Markers in Children with Sickle Cell Disease from the Northeast of Brazil

We investigated the nasopharynx and oropharynx microbiota in sickle cell disease (SCD) to identify the microorganisms, antibiotic sensitivity, prevalent serotypes, and association of with laboratorial markers. Oropharynx/nasopharynx secretions were investigated in 143 SCD children aging 6 months to 17 years. Pathogens were isolated using standard procedures, and laboratorial markers were performed by automated methods. Staphylococcus aureus (S. aureus) was isolated from nasopharynx and oropharynx of 64 and of 17 SCD children respectively. Streptococcus pneumoniae (S. pneumoniae) was isolated from the nasopharynx and oropharynx of eight SCD patients. Serotypes of S. pneumoniae were 19F, 23F, and 14. All isolates were susceptible to penicillin, and patients whose nasopharynx and oropharynx were colonized by S. pneumoniae had high concentrations of aspartate transaminase, alanine transaminase, and ferritin. S. pneumoniae isolated were not penicillin-resistant serotypes suggesting that the use of penicillin for prophylaxis and/or treatment of infections is safe. Our finding of colonization and laboratory evaluation in SCD patients suggests that microorganisms are involved in the modulation of chronic inflammatory. The association of colonized microorganisms and laboratorial markers suggest a new approach to these patients follow-up, and additional studies of microorganism colonization and their association with SCD patients' clinical outcome will improve control and prevention strategies.

Risk factors for mortality in adult patients with sickle cell disease: a meta-analysis of studies in North America and Europe

Although recent studies show an improved survival of children with sickle cell disease in the US and Europe, for adult patients mortality remains high. This study was conducted to evaluate the factors associated with mortality in adult patients following the approval of hydroxyurea. We first evaluated the association between selected variables and mortality at an academic center (University of North Carolina). Data sources were then searched for publications from 1998 to June 2016, with meta-analysis of eligible studies conducted in North America and Europe to evaluate the associations of selected variables with mortality in adult patients. Nine studies, combined with the UNC cohort (total n=3257 patients) met the eligibility criteria. Mortality was significantly associated with age (per 10-year increase in age) [7 studies, 2306 participants; hazard ratio (HR): 1.28; 95% confidence interval (CI): 1.10-1.50], tricuspid regurgitant jet velocity 2.5 m/s or more (5 studies, 1577 participants; HR: 3.03; 95%CI: 2.0-4.60), reticulocyte count (3 studies, 1050 participants; HR: 1.05; 95%CI: 1.01-1.10), log(N-terminal-pro-brain natriuretic peptide) (3 studies, 800 participants; HR: 1.68; 95%CI: 1.48-1.90), and fetal hemoglobin (7 studies, 2477 participants; HR: 0.97; 95%CI: 0.94-1.0). This study identifies variables associated with mortality in adult patients with sickle cell disease in the hydroxyurea era.

Pediatric sickle cell disease: past successes and future challenges

Once a fatal disease of childhood, more than 95% of patients born today with sickle cell disease (SCD) in developed countries are expected to survive into adulthood, largely because of improvements in supportive and preventive care (newborn screening, penicillin prophylaxis, transcranial Doppler (TCD) screening). Hydroxyurea (HU) therapy, the only oral medication currently available to prevent SCD complications, has become more widespread over the past 20 y. The NHLBI recommends that HU be offered to all patients with HbSS beginning at 9 mo of age, and the recently published Abnormal TCD with Transfusions Changing to HU (TWiTCH) trial has shown HU as an acceptable alternative to transfusion therapy for patients at high risk of stroke. While hematopoietic stem cell transplant (HSCT) is a curative option for SCD, less than 25% of patients have a suitable donor. Alternative stem cell sources from unrelated donors and haplo-identical donors are currently under investigation as are gene therapy trials. This review will focus on early efforts to elucidate SCD pathophysiology as well as supportive and preventive care improvements. Findings from recent multi-center studies (Silent Infarct Transfusion (SIT) Trial and TWiTCH) will be summarized. Finally, HSCT trials and gene therapy will be reviewed.

CT abdominal imaging findings in patients with sickle cell disease: acute vaso-occlusive crisis, complications, and chronic sequelae

Sickle cell disease (SCD) is the most prevalent hemoglobinopathy. Survival in patients with SCD has improved over the past few decades. These patients experience a lifetime of repeated acute pain crises, which are thought to result from sickling and microvascular occlusions; acute abdominal pain is common. Moreover, repeated crises often lead to organ dysfunction, such as asplenia, hepatic failure, and renal failure. The spleen, liver, biliary system, kidneys, and gastrointestinal tract can all be affected. Patients may undergo CT to further direct clinical management. We review the spectrum of CT imaging findings of abdominal manifestations in patients with SCD, from the acute microvascular occlusive pain crisis to the potential complications and chronic sequelae.

Survival of children with sickle cell disease in the comprehensive newborn screening programme in Minas Gerais, Brazil

BACKGROUND

Children in developing countries with sickle cell disease SCD have high rates of mortality, especially in some parts of Africa.

AIM

To compare the 5-year estimated mortality rate in children born between 1999 and 2001 with that of children born between 2009 and 2011.

METHODS

During the period 1998-2012, sickle cell disease was diagnosed in 2591 of 3,617,919 newborns screened in Minas Gerais, Brazil (1 : 1,400). The estimated probability of death [1 - Survival] was calculated by the Kaplan-Meier method. The logrank test was used to compare groups of survival data.

RESULTS

Of the 2576 children (15 were excluded), 193 died (7.4%): 153 (79.3%) had SS/Sβ(0)-thalassaemia, 34 had SC (17.6%), and six (3.1%) had Sβ(+) thalassaemia. The 5-year estimated mortality was lower for children born between 2009 and 2011 (n=509) than for those born between 1999 and 2001 (n=624), although not significantly [mean (SD) 5.8% (1.1) vs 6.2% (1.0)], respectively).

CONCLUSION

Despite an effective ongoing comprehensive screening programme, mortality from SCD in Minas Gerais is still high. To decrease mortality rates, socio-economic development and SCD education programmes for health professionals and families are required.

Interventions for patients and caregivers to improve knowledge of sickle cell disease and recognition of its related complications

BACKGROUND

Sickle cell disease is a group of genetic diseases which is especially prevalent in tropical and subtropical regions; however, forced migration and ongoing population movement have spread it throughout the world, with estimated birth rates reaching 0.49 per 1000 in the Americas, 0.07 per 1000 in Europe, 0.68 per 1000 in South and Southeast Asia, and 10.68 per 1000 in Africa. Life for individuals with sickle cell disease can be affected by repeated acute complications and compounded by progressive organ damage. Studies reveal that when people with chronic illness learn self-management, their clinical outcomes and quality of life improves; and they show lower dependence on healthcare services. There are, however, no reviews identifying which interventions improve knowledge and little is known about the impact of patient or care-giver knowledge on clinical and psychosocial outcomes in people with sickle cell disease.

OBJECTIVES

1. To determine the effectiveness of patient- and caregiver-centred educational interventions for changing knowledge and understanding of sickle cell disease among patients as well as caregivers of people with the disease.2. To assess the effectiveness and safety of patient- and caregiver-centred educational interventions and programs for the recognition of signs and symptoms of disease-related morbidity, adherence to treatment and healthcare utilization in patients with sickle cell disease.

SEARCH METHODS

The authors searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Additional trials were sought from the reference lists of the trials and reviews identified by the search strategy.Date of last search: 11 April 2016.

SELECTION CRITERIA

Randomized and quasi-randomized controlled trials which evaluate the effectiveness of individual- and group-based interventions for either the patient with sickle cell disease or their caregivers, or both. Eligible interventions will aim to change knowledge, attitudes or skills, improve psychosocial aspects of the disease as well as treatment adherence and healthcare utilization. Trials evaluating the intervention versus no program, comparing two interventions and those which are part of a multi-faceted intervention to improve a range of sickle cell-related health outcomes are all eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected trials based on stated inclusion criteria and thereafter examined each selected report to extract data using a prepared, piloted, data collection form. A third author assisted in reaching consensus if there were any discrepancies. Similarly, risk of bias was assessed by two authors and verified by a third author.

MAIN RESULTS

A total of 12 trials (11 randomized controlled trials and one quasi-randomized trial) of 563 people with HbSS, HbSC or HbSβthal, aged six to 35 years old, were included in the review; the majority of participants were African-American. Interventions ranged from a total of one hour to weekly sessions for eight weeks and the post-intervention assessments ranged from the end of the intervention period to 12 months after completion. The heterogeneity of the included trials, which encompasses setting, inclusion and exclusion criteria, interventional method and time of assessment, ranged from 'not important' to 'moderate to substantial' for different review outcomes. The overall risk of bias was low for selective reporting, unclear for random sequence generation, allocation concealment, blinding of participants and blinding of outcome assessment. Incomplete outcome reporting and blinding of personnel showed mixed bias representations.Patient knowledge was assessed by four trials (160 participants) with moderate to substantial heterogeneity. There was evidence that educational programs improved patient knowledge, standardised mean difference 0.87 points (95% confidence interval 0.28 to 1.45, moderate quality evidence), which improved further when a trial with high bias was removed in a sensitivity analysis. Caregiver knowledge, reported in a single trial of 20 families, also showed an improvement, standardised mean difference 0.52 points (95% confidence interval 0.03 to 1.00, moderate quality evidence). The effect on patient knowledge was sustained at longer follow-up periods, whereas the effect on caregiver knowledge was not sustained.There were two primary outcomes related to the effectiveness of educational programs on the recognition of signs and symptoms of disease-related morbidity. No comparative data were reported for patients or caregivers (or both) recognising signs and symptoms leading to self-management. Data from two trials were analysed for the utilization of health services and showed no evidence of an effect, mean difference 0.33 (95% confidence interval -0.57 to 1.23, moderate quality evidence).With regard to the review's secondary outcomes, depression showed a statistically significant decline in intervention groups, standardised mean difference -0.66 points (95% confidence interval -1.18, to -0.14, moderate quality evidence). Adherence to treatment was not assessed in any of the identified trials. No effects of interventions were seen on coping, family relationships or health-related quality of life of patients.The quality of evidence was low for positive coping and moderate for child knowledge, healthcare utilization and depression. This suggests that further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimates.

AUTHORS' CONCLUSIONS

This review identifies important positive effects of educational interventions on improving patient knowledge of sickle cell disease and depression. Effects on patients' knowledge were maintained for longer than for caregivers. The effect on knowledge was significant but small and whether it offers any clinical benefit is uncertain. Significant factors limiting these effects could be trials being under powered as well as attrition rates. Effects were not statistically significant in assessments of secondary outcomes, possibly due to the paucity of the number of trials and patients and caregivers. Trials showed moderate to high heterogeneity which might impact the results. To better study effects on outcomes, further controlled trials are needed with rigorous attention given to improve recruitment and retention and to decrease bias. Predetermined protocols using similar measurements should be used across multiple sites.

Renal Failure in Sickle Cell Disease: Prevalence, Predictors of Disease, Mortality and Effect on Length of Hospital Stay

Renal dysfunction in sickle cell disease is not only a chronic comorbidity but also a mortality risk factor. Though renal dysfunction starts early in life in sickle cell patients, the predictors that can identify sickle cell disease patients at risk of developing renal dysfunction is not known. We used the Truven Health MarketScan^® Medicaid Databases from 2007 to 2012. Incidence of new acute renal failure (ARF) and chronic kidney disease (CKD) was calculated in this cohort. There were 9481 patients with a diagnosis of sickle cell disease accounting for 64,201 hospital admissions, during the study period. Both ARF and CKD were associated with higher risk of inpatient mortality, longer duration of the hospital stay and expensive hospitalizations. The yearly incidence of new ARF in sickle cell disease patients was 1.4% and annual CKD incidence was 1.3%. The annual rate of new ARF and CKD in the control group was 0.4 and 0.6%, respectively. The most important predictors of new CKD were proteinuria, ARF and hypertension. Chronic kidney disease, hypertension and sickle cell crisis were the most important predictors of new ARF. The annual rate of incidences of ARF and CKD were 2- to 3-fold higher in sickle cell disease compared to the non sickle cell disease group. Besides the common risk factors for renal disease in the general population, it is imperative to monitor the sickle cell disease patients with more severe disease to prevent them from developing renal dysfunction.

Sickle cell anemia mice develop a unique cardiomyopathy with restrictive physiology

Cardiopulmonary complications are the leading cause of mortality in sickle cell anemia (SCA). Elevated tricuspid regurgitant jet velocity, pulmonary hypertension, diastolic, and autonomic dysfunction have all been described, but a unifying pathophysiology and mechanism explaining the poor prognosis and propensity to sudden death has been elusive. Herein, SCA mice underwent a longitudinal comprehensive cardiac analysis, combining state-of-the-art cardiac imaging with electrocardiography, histopathology, and molecular analysis to determine the basis of cardiac dysfunction. We show that in SCA mice, anemia-induced hyperdynamic physiology was gradually superimposed with restrictive physiology, characterized by progressive left atrial enlargement and diastolic dysfunction with preserved systolic function. This phenomenon was absent in WT mice with experimentally induced chronic anemia of similar degree and duration. Restrictive physiology was associated with microscopic cardiomyocyte loss and secondary fibrosis detectable as increased extracellular volume by cardiac-MRI. Ultrastructural mitochondrial changes were consistent with severe chronic hypoxia/ischemia and sarcomere diastolic-length was shortened. Transcriptome analysis revealed up-regulation of genes involving angiogenesis, extracellular-matrix, circadian-rhythm, oxidative stress, and hypoxia, whereas ion-channel transport and cardiac conduction were down-regulated. Indeed, progressive corrected QT prolongation, arrhythmias, and ischemic changes were noted in SCA mice before sudden death. Sudden cardiac death is common in humans with restrictive cardiomyopathies and long QT syndromes. Our findings may thus provide a unifying cardiac pathophysiology that explains the reported cardiac abnormalities and sudden death seen in humans with SCA.

Care Coordination for Children With Sickle Cell Disease: A Longitudinal Study of Parent Perspectives and Acute Care Utilization

INTRODUCTION

Care coordination (CC), a core element of the medical home, has the potential to reduce fragmented care and improve patient experience for children with sickle cell disease (SCD). This study aimed to (1) assess CC for pediatric SCD and (2) determine its association with acute care utilization-emergency department encounters and hospitalizations. It was hypothesized that CC would reduce acute care utilization.

METHODS

A longitudinal study of 101 children with SCD was conducted. Parents completed a survey instrument on enrollment. Utilization chart review was conducted 9 months post survey. Outcome variables were emergency department encounters and hospitalizations. Independent variables were parent-reported CC, satisfaction with communication between healthcare providers, and satisfaction with communication between healthcare providers and non-medical providers (e.g., schools, child care centers). Multivariate negative binomial regression was conducted to assess associations between CC and acute care utilization. Data were collected in 2011-2013 and analyzed in 2015.

RESULTS

One third of children had emergency department encounters and 30% had hospitalizations. At enrollment, 25% of parents reported receiving CC help and 20% reported need for extra CC. Most parents were satisfied with communication between physicians but only two thirds were satisfied with communication between their healthcare providers and non-medical providers. No significant associations were found between CC measures and acute care utilization.

CONCLUSIONS

Although parents report multiple CC deficiencies, no associations were found between CC and acute care utilization. Population-based studies are warranted to more definitively determine the association between CC and acute care utilization for children with SCD.

Nonhematopoietic Nrf2 dominantly impedes adult progression of sickle cell anemia in mice

The prevention of organ damage and early death in young adults is a major clinical concern in sickle cell disease (SCD). However, mechanisms that control adult progression of SCD during the transition from adolescence are poorly defined with no cognate prophylaxis. Here, we demonstrate in a longitudinal cohort of homozygous SCD (SS) mice a link between intravascular hemolysis, vascular inflammation, lung injury, and early death. Prophylactic Nrf2 activation in young SS mice stabilized intravascular hemolysis, reversed vascular inflammation, and attenuated lung edema in adulthood. Enhanced Nrf2 activation in endothelial cells in vitro concurred with the dramatic effect on vascular inflammation in the mice. BM chimeric SS mice lacking Nrf2 expression in nonhematopoietic tissues were created to dissect the role of nonerythroid Nrf2 in SCD progression. The SS chimeras developed severe intravascular hemolysis despite having erythroid Nrf2. In addition, they developed premature vascular inflammation and pulmonary edema and died younger than donor littermates with intact nonhematopoietic Nrf2. Our results reveal a dominant protective role for nonhematopoietic Nrf2 against tissue damage in both erythroid and nonerythroid tissues in SCD. Furthermore, we show that prophylactic augmentation of Nrf2-coordinated cytoprotection effectively impedes onset of the severe adult phenotype of SCD in mice.

Long-term treatment follow-up of children with sickle cell disease monitored with abnormal transcranial Doppler velocities

Children with normalized TCD on transfusions were safely switched to hydroxyurea treatment, but trimestrial Doppler follow-up is required. Allogeneic transplant allowed the safe stop of transfusions in all patients, even in those with abnormal velocities before transplant.

Minireview: Clinical severity in sickle cell disease: the challenges of definition and prognostication

Sickle cell disease (SCD) is a monogenic, yet highly phenotypically variable disease with multisystem pathology. This manuscript provides an overview of many of the known determinants, modifiers, and correlates of disease severity in SCD. Despite this wealth of data, modeling the variable and multisystem pathology of SCD continues to be difficult. The current status of prediction of specific adverse outcomes and global disease severity in SCD is also reviewed, highlighting recent successes and ongoing challenges.

Minireview: Multiomic candidate biomarkers for clinical manifestations of sickle cell severity: Early steps to precision medicine

In this review, we provide a description of those candidate biomarkers which have been demonstrated by multiple-omics approaches to vary in correlation with specific clinical manifestations of sickle cell severity. We believe that future clinical analyses of severity phenotype will require a multiomic analysis, or an omics stack approach, which includes integrated interactomics. It will also require the analysis of big data sets. These candidate biomarkers, whether they are individual or panels of functionally linked markers, will require future validation in large prospective and retrospective clinical studies. Once validated, the hope is that informative biomarkers will be used for the identification of individuals most likely to experience severe complications, and thereby be applied for the design of patient-specific therapeutic approaches and response to treatment. This would be the beginning of precision medicine for sickle cell disease.

Acute gastrointestinal vaso-occlusive ischemia in sickle cell disease: CT imaging features and clinical outcome

PURPOSE

The purpose of this study was to determine the incidence, specific imaging features, and outcome of gastrointestinal vaso-occlusive ischemia (GVOI) in sickle cell patients undergoing CT for acute abdominal pain.

METHODS

This HIPAA-compliant, IRB-approved retrospective study evaluated sickle cell patients with an abdominal pain crisis and acute gastrointestinal abnormalities on CT from 1/2006 to 1/2014. CT findings were divided into those compatible and incompatible with bowel ischemia or clinical diagnosis of GVOI. Two abdominal radiologists (1, 13 years' experience) reviewed the CTs for specific imaging features of ischemia. Clinical laboratory values (lactate, WBC) and outcome were recorded. Descriptive statistics and Wilcoxon-Mann-Whitney two-sample rank-sum test were performed.

RESULTS

Of 217 CTs, 33 had acute gastrointestinal abnormalities: 75% (25/33) consistent with ischemia and clinical GVOI. Complications of ischemia occurred in 16% (4/25): ileus (50%), perforation (25%), and pneumatosis (25%). In uncomplicated cases, all had bowel wall thickening: segmental 52% (11/21) or diffuse 48% (10/21). The colon was commonly involved (76%, 16/21), particularly the ascending (57%, 12/21). Most abnormalities (52%, 11/21) were in the superior mesenteric artery distribution. Average lactate (4.3 ± 4.0 mmol/L, p = 0.02) and WBC count (20.1 ± 10.4, ×1000 cells/μL, p = 0.01) were significantly higher in GVOI. Overall mortality in patients with GVOI was 17% (3/18).

CONCLUSION

GVOI is an important feature of the acute abdominal crisis in patients with sickle cell disease and can be seen in up to 75% of patients with abnormal bowel findings on CT. The diagnosis should be strongly considered in sickle cell patients with CT findings of diffuse or segmental bowel wall thickening, particularly involving the colon.

Defining Sickle Cell Disease Mortality Using a Population-Based Surveillance System, 2004 through 2008

OBJECTIVE

Population-based surveillance data from California and Georgia for years 2004 through 2008 were linked to state death record files to determine the all-cause death rate among 12,143 patients identified with sickle cell disease (SCD).

METHODS

All-cause death rates, by age, among these SCD patients were compared with all-cause death rates among both African Americans and the total population in the two states. All-cause death rates were also compared with death rates for SCD derived from publicly available death records: the compressed mortality files and multiple cause of death files.

RESULTS

Of 12,143 patients identified with SCD, 615 patients died. The all-cause mortality rate for the SCD population was lower than the all-cause mortality rate among African Americans and similar to the total population all-cause mortality rates from birth through age 4 years, but the rate was higher among those with SCD than both the African American and total population rates from ages 5 through 74 years. The count of deceased patients identified by using population-based surveillance data (n=615) was more than twice as high as the count identified in compressed mortality files using SCD as the underlying cause of death alone (n=297).

CONCLUSION

Accurate assessment of all-cause mortality and age at death requires long-term surveillance via population-based registries of patients with accurately diagnosed SCD.

Neonatal Screening and the Clinical Outcome in Children with Sickle Cell Disease in Central India

BACKGROUND

Sickle cell disease (SCD) is a major health burden in India. The objective of the study was to establish a neonatal screening program and to understand the clinical course of children with SCD in central India.

METHODS AND FINDINGS

Pregnant mothers were screened for sickle hemoglobin using the solubility test. Babies were screened by high performance liquid chromatography if the mother was positive for sickle hemoglobin. The diagnosis was confirmed by molecular analysis. They received early prophylactic treatment and vaccination. Of 2134 newborns screened, 104 were sickle homozygous (SS), seven had sickle β-thalassemia (S-β thal) and 978 were sickle heterozygous (AS). The other hemoglobin abnormalities detected included HbS-δβ thalassemia-1, HbSD disease-2, HbE traits-5, β-thalassemia traits-4, alpha chain variants-3 and HbH disease-1.These babies were followed up regularly for hematological and clinical evaluation. Pain, severe anemia requiring blood transfusions and acute febrile illness were the major complications with 59.7, 45.1 and 42.6 cases per 100 person years. Fetal hemoglobin (HbF) levels were inversely associated with vaso-oclussive crisis (VOC) and severe anemia while presence of alpha thalassemia increased the rate of painful events and sepsis. Six early deaths occurred among the SS babies.

CONCLUSION

A systematic follow up of this first newborn SCD cohort in central India showed that 47% of babies presented within 1 year of age. In spite of the presence of the Arab-Indian haplotype many babies had severe manifestations.

Validation of a Low-Cost Paper-Based Screening Test for Sickle Cell Anemia

Background

The high childhood mortality and life-long complications associated with sickle cell anemia (SCA) in developing countries could be significantly reduced with effective prophylaxis and education if SCA is diagnosed early in life. However, conventional laboratory methods used for diagnosing SCA remain prohibitively expensive and impractical in this setting. This study describes the clinical validation of a low-cost paper-based test for SCA that can accurately identify sickle trait carriers (HbAS) and individuals with SCA (HbSS) among adults and children over 1 year of age.

Methods and Findings

In a population of healthy volunteers and SCA patients in the United States (n = 55) the test identified individuals whose blood contained any HbS (HbAS and HbSS) with 100% sensitivity and 100% specificity for both visual evaluation and automated analysis, and detected SCA (HbSS) with 93% sensitivity and 94% specificity for visual evaluation and 100% sensitivity and 97% specificity for automated analysis. In a population of post-partum women (with a previously unknown SCA status) at a primary obstetric hospital in Cabinda, Angola (n = 226) the test identified sickle cell trait carriers with 94% sensitivity and 97% specificity using visual evaluation (none of the women had SCA). Notably, our test permits instrument- and electricity-free visual diagnostics, requires minimal training to be performed, can be completed within 30 minutes, and costs about $0.07 in test-specific consumable materials.

Conclusions

Our results validate the paper-based SCA test as a useful low-cost tool for screening adults and children for sickle trait and disease and demonstrate its practicality in resource-limited clinical settings.

The Changing Epidemiology of Pediatric Hemoglobinopathy Patients in Northern Alberta, Canada

BACKGROUND

Hemoglobinopathies are associated with significant morbidity and mortality. Accurate epidemiologic data reflecting the number of hemoglobinopathy patients are lacking in Canada. Immigration patterns are shifting such that regions where these diseases were rare are seeing a rapid population expansion, revealing a gap in the health care system and the need for a public health response.

METHODS

To understand the epidemiology of pediatric hemoglobinopathy patients given the provincial population growth and immigration patterns, a retrospective chart review was conducted at the Stollery Children's Hospital from January 2004 to July 2014.

RESULTS

A total of 88% of patients had sickle cell disease; 55% of patients were Canadian born and 63% of families originated from Africa. There was a 3.5-fold increase in patient numbers with acceleration in patient accrual over the study period and a delay in diagnosis in 70% of patients. There was a significant increase in the number of hospitalizations over the study period. Thirteen percent required at least 1 exchange transfusion, 16% received chronic transfusions, and 30% of patients developed at least 1 severe complication related to their diagnosis.

CONCLUSIONS

It is imperative to demonstrate the growing hemoglobinopathy population and changing health care requirements to advocate for appropriate resources, educate health care providers, and increase awareness.