Evidence review of hydroxyurea for the prevention of sickle cell complications in low-income countries

Current and emerging drug treatment strategies to tackle sickle cell anemia

INTRODUCTION

Since its discovery in the early 1900s, sickle cell disease (SCD) has contributed significantly to the scientific understanding of hemoglobin and hemoglobinopathies. Despite this, now almost a century later, optimal medical management and even curative options remain limited. Encouragingly, in the last decade, there has been a push toward advancing the care for individuals with SCD and a diversifying interest in options to manage this disorder.

AREAS COVERED

Here, we review the current state of disease modifying therapies for SCD including fetal hemoglobin inducers, monoclonal antibodies, anti-inflammatory modulators, and enzyme activators. We also discuss current curative strategies with specific interest in transformative gene therapies.

EXPERT OPINION

SCD is a chronic, progressive disease that despite a century of clinical description, only now is seeing a growth and advance in therapeutic options to improve the lifespan and quality of life for individuals with SCD. We anticipate newly designed and even repurposed therapies that may work as a single agent or combination agents to tackle the progression of SCD. The vast majority of individuals living with SCD are unlikely to receive gene therapy, therefore improved disease management is critical even for those that may ultimately chose to pursue a potentially curative strategy.

The magic of a methyl group: Biochemistry at the service of medicine

A carbon-carbon linkage is created when a methyl group is implanted on dUMP, thus resulting in the formation of dTMP by thymidylate synthase. The methyl group is deleted by aromatase when androgens are converted to estrogens. The methyl group is rearranged with the help of vitamin B12 in the isomerization of methylmalonyl-CoA to succinyl-CoA. S-adenosylmethionine (SAM) serves as the universal methyl donor involved in the biosynthesis of adrenaline and creatine(phosphate). It also interferes with the 5'-mRNA capping and the degradation of catecholamines (i.e. adrenaline, noradrenaline). Cholesterol could be viewed as a conglomeration of methyl groups. Finally, as part of valine, two methyl functions participate in the origin of one of the most frequent hereditary diseases on earth, sickle cell anemia.

Impact of the SARS-CoV-2 infection in individuals with sickle cell disease: an integrative review

Sickle cell disease is the most common hemoglobinopathy among humans. As the condition promotes susceptibility to infections, chronic inflammation, and hypercoagulability disorders, several international agencies have included individuals with this disease in the COVID-19 risk group for severe outcomes. However, available information about the subject is not properly systematized yet. This review aimed to understand and summarize the scientific knowledge about the impact of SARS-CoV-2 infection in patients with sickle cell disease. Searches were performed in the Medline, PubMed, and Virtual Health Library databases based on descriptors chosen according to the Medical Subject Headings. We analyzed studies published between 2020 and October 2022, developed with qualitative, quantitative, or mixed methodology, and written in English, Spanish, or Portuguese. The search resulted in 90 articles organized into six categories. There is disagreement in the literature about how different aspects related to sickle cell disease, such as chronic inflammation status, hypercoagulability, hemolytic anemia, use of hydroxyurea, and access to medical care interference with the clinical course of COVID-19. These topics deserve further investigation. It is evident, however, that the infection may manifest in an atypical way and act as a trigger for the development of sickle cell-specific complications, such as acute chest syndrome and vaso-occlusive crises, conditions that are associated with great morbidity and mortality. Therefore, healthcare professionals must be aware of the different forms of presentation of COVID-19 among these individuals. Specific guidelines and therapeutic protocols, as well as public policies for sickle cell individuals, must be considered.

Systematic review registration

This review (https://doi.org/10.17605/OSF.IO/NH4AS) and the review protocol (https://osf.io/3y649/) are registered in the Open Science Framework platform.

Blood Transfusion Vs. Hydroxyurea for Stroke Prevention in Children With Sickle Cell Anemia: A Systematic Review and Meta-Analysis

Sickle cell anemia (SCA) is a hereditary condition that can lead to severe complications in children such as acute coronary syndrome, splenic sequestration, renal failure, and stroke. Blood transfusion and hydroxyurea (HU) therapy are used to prevent stroke in children with sickle cell disease (SCD). Preliminary data show considerable variation and inconsistency in the use of these two therapeutic interventions. Therefore, this systematic review was carried out to compare the effects of blood transfusion to HU therapy in preventing stroke for children with sickle cell disease. There was an extensive literature search in reliable and authentic databases like PubMed, Medline, Scopus, Cochrane, and Science Direct to obtain relevant articles. This study used the standards and guidelines from the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). During the systematic review, data were obtained focusing on the following parameters: the size of the sample in the study, the age of the subjects involved in the study, the type of Intervention, and the outcome. After an initial search of 163 papers, 25 studies were included. The results of the research give the first evidence that HU is effective in the treatment of cerebrovascular problems in children with SCD. However, it is unclear under what circumstances HU may prevent a second stroke. It can be concluded that children with SCA can effectively avoid primary strokes through chronic blood transfusions and HU.

What can work and how? An overview of evidence-based interventions and delivery strategies to support health and human development from before conception to 20 years

Progress has been made globally in improving the coverage of key maternal, newborn, and early childhood interventions in low-income and middle-income countries, which has contributed to a decrease in child mortality and morbidity. However, inequities remain, and many children and adolescents are still not covered by life-saving and nurturing care interventions, despite their relatively low costs and high cost-effectiveness. This Series paper builds on a large body of work from the past two decades on evidence-based interventions and packages of care for survival, strategies for delivery, and platforms to reach the most vulnerable. We review the current evidence base on the effectiveness of a variety of essential and emerging interventions that can be delivered from before conception until age 20 years to help children and adolescents not only survive into adulthood, but also to grow and develop optimally, support their wellbeing, and help them reach their full developmental potential. Although scaling up evidence-based interventions in children younger than 5 years might have the greatest effect on reducing child mortality rates, we highlight interventions and evidence gaps for school-age children (5-9 years) and the transition from childhood to adolescence (10-19 years), including interventions to support mental health and positive development, and address unintentional injuries, neglected tropical diseases, and non-communicable diseases.

Hydroxyurea- a cost effective treatment in developing countries for Atypical Chronic Myeloid Leukemia (aCML): Case Report of Two Patients

INTRODUCTION

Atypical chronic myeloid leukaemia (aCML) is a rare chronic myeloproliferative disorder with a poor prognosis.

CASE REPORT

This case report presents two cases of male geriatric patients, both referred from primary care in rural areas and received at an urban clinic in a tertiary care hospital on separate instances. The first patient complained of low-grade fever (on/off), generalized body aches, rapid weight loss and shortness of breath for the last 2 months. The second patient arrived pale looking with symptoms of generalized body aches, dizziness and anorexia. Both patients were diagnosed to have aCML according to the World Health organization criteria.

MANAGEMENT & OUTCOME

Both the patients were from a low economic bracket and were treated with Hydroxyurea a relatively economic medicine successfully. The follow-up lasted for 12 months in both cases. No progression to acute myeloid leukaemia (AML) or relapse was observed.

DISCUSSION

This case report shows the promising results of Hydroxyurea in treating aCML and can be a cost effective alternate to other expensive treatments (allogeneic hematopoietic stem cell transplantation) and expensive medicines in lower and middle-income countries especially for resource-limited patients. These two cases show promising evidence for further studies to evaluate and conduct pharmaco-economic evaluations as well as clinical trials to compare hydroxyurea with other available alternative treatments for an affordable therapeutic option towards prevention of relapse and disease free survival after aCML.

Analysis of Causes of Hospitalization Among Children with Sickle Cell Disease in a Group of Private Hospitals in Jeddah, Saudi Arabia

Purpose

Sickle cell anemia (SCA) is a chronic hematologic condition that requires frequent hospitalization representing a significant economic burden on the health services. The aim of this study was to explore the causes and underlying factors of hospitalization among children with SCA, as well as the factors affecting their length of hospital stay.

Patients and Methods

This retrospective study included children and adolescents less than 16 years old who were admitted in a group of private hospitals in Jeddah, Saudi Arabia, during the period from January 2018 to December 2019.

Results

A total of 94 patients were included in this study, 59.6% were males, with a mean age 7.29 ± 3.82 years. The majority of the patients (91.5%) had sickle cell disease. The most common cause of hospital admission was vaso-occlusive crises (VOC) (64.9%) followed by infection (24.5%), acute chest syndrome (ACS) (18.1%), and acute hemolytic crisis (12.8%). We found no significant difference between gender and different causes of admissions (p > 0.05). While in relation to age group, limb pain and back pain were found to be significantly more frequent among children ≥ 7 years old (p = 0.03,0.04), while infections were significantly more frequent among children < 7 years old (p = 0.003). We analyzed the length of hospital stay and different factors, and we found that the mean length of hospital stay was significantly higher among children who were admitted with infections (p = 0.01) and ACS (p < 0.001) and among children who are non-compliant on hydroxyurea (p = 0.04).

Conclusion

The most common cause of hospitalization among children with SCD in Jeddah, Saudi Arabia, was VOC followed by infection, ACS and acute anemia. The length of hospital stay was more prolonged among children with infection and ACS, as well as children who were non-compliant to hydroxyurea.

Implementation of the therapeutic use of hydroxyurea for sickle cell disease management in resource-constrained settings: a systematic review of adoption, cost and acceptability

OBJECTIVES

Mortality associated with sickle cell disease (SCD) is high in many low- and middle-income countries (LMICs). Hydroxyurea, a medicine to effectively manage SCD, is not widely available in resource-constrained settings. We identified and synthesised the reported implementation outcomes for the therapeutic use of hydroxyurea for SCD in these settings.

DESIGN

Systematic review.

DATA SOURCES

PubMed, Embase, Cochrane, Web of Science Plus, Global Health, CINAHL, and PsycINFO were searched February through May 2019 without any restrictions on publication date.

ELIGIBILITY CRITERIA

We included empirical studies of hydroxyurea for management of SCD that were carried out in LMICs and reported on implementation outcomes.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently assessed studies for inclusion, carried out data extraction using Proctor et al.'s implementation and health service outcomes, and assessed the risk of bias using ROBINS-I (Risk Of Bias In Non-randomised Studies - of Interventions).

RESULTS

Two cross-sectional surveys (n=2) and one cohort study (n=1) reported implementation of hydroxyurea for SCD management, namely regarding outcomes of adoption (n=3), cost (n=3) and acceptability (n=1). These studies were conducted exclusively among paediatric and adults populations in clinical settings in Nigeria (n=2) or Jamaica (n=1). Adoption is low, as observed through reported provider practices and patient adherence, in part shaped by misinformation and fear of side effects among patients, provider beliefs regarding affordability and organisational challenges with procuring the medicine. There was no difference in the cost of hydroxyurea therapy compared with blood transfusion in the paediatric population in urban Jamaica. Risk of bias was low or moderate across the included studies.

CONCLUSIONS

This review rigorously and systematically assessed the evidence on implementation of hydroxyurea in resource-constrained settings such as LMICs. Findings suggest that knowledge regarding implementation is low. To address the know-do gap and guide clinical practice, implementation research is needed. Integrating effective interventions into existing health systems to improve hydroxyurea uptake is essential to reducing SCD-associated mortality.

PROSPERO REGISTRATION NUMBER

CRD42020155953.

Angelicin-A Furocoumarin Compound With Vast Biological Potential

Angelicin, a member of the furocoumarin group, is related to psoralen which is well known for its effectiveness in phototherapy. The furocoumarins as a group have been studied since the 1950s but only recently has angelicin begun to come into its own as the subject of several biological studies. Angelicin has demonstrated anti-cancer properties against multiple cell lines, exerting effects via both the intrinsic and extrinsic apoptotic pathways, and also demonstrated an ability to inhibit tubulin polymerization to a higher degree than psoralen. Besides that, angelicin too demonstrated anti-inflammatory activity in inflammatory-related respiratory and neurodegenerative ailments via the activation of NF-κB pathway. Angelicin also showed pro-osteogenesis and pro-chondrogenic effects on osteoblasts and pre-chondrocytes respectively. The elevated expression of pro-osteogenic and chondrogenic markers and activation of TGF-β/BMP, Wnt/β-catenin pathway confirms the positive effect of angelicin bone remodeling. Angelicin also increased the expression of estrogen receptor alpha (ERα) in osteogenesis. Other bioactivities, such as anti-viral and erythroid differentiating properties of angelicin, were also reported by several researchers with the latter even displaying an even greater aptitude as compared to the commonly prescribed drug, hydroxyurea, which is currently on the market. Apart from that, recently, a new application for angelicin against periodontitis had been studied, where reduction of bone loss was indirectly caused by its anti-microbial properties. All in all, angelicin appears to be a promising compound for further studies especially on its mechanism and application in therapies for a multitude of common and debilitating ailments such as sickle cell anaemia, osteoporosis, cancer, and neurodegeneration. Future research on the drug delivery of angelicin in cancer, inflammation and erythroid differentiation models would aid in improving the bioproperties of angelicin and efficacy of delivery to the targeted site. More in-depth studies of angelicin on bone remodeling, the pro-osteogenic effect of angelicin in various bone disease models and the anti-viral implications of angelicin in periodontitis should be researched. Finally, studies on the binding of angelicin toward regulatory genes, transcription factors, and receptors can be done through experimental research supplemented with molecular docking and molecular dynamics simulation.

Hydroxyurea can be used in children with sickle cell disease and cerebral vasculopathy for the prevention of chronic complications? A meta-analysis

We conducted a systematic review for evaluating the impact of hydroxyurea and chronic blood transfusion in children with sickle cell disease (SCD). A search was done in four databases from inception to 2017. Trials enrolling pediatric patients with SCD and cerebral vasculopathy with or without previous episode of stroke and that reported outcomes of occurrence of stroke and other events were included. Trained reviewers determined eligibility, risk of bias, and abstracted data. Random-effects meta-analysis was conducted. We found that the primary outcome was the occurrence of stroke. We found two trials that recruited 254 patients. No difference was found for confirmed stroke occurrence (risk difference 0.04 [95% CI: -0.03 to 0.03]) and for new-onset neurological deficit (risk difference 0.11 [95% CI: -0.00 to 0.21]). Transfusions provided a significant lower risk of vaso-occlussive crisis (risk difference 0.10 [95% CI: 0.001 to 0.20]). Finally, transfusions provided a lower risk of having high concentrations of abnormal hemoglobin S (mean difference 37.94 [95% CI: 27.55 to 48.32]). As a conclusion, transfusions plus chelation therapy might be used instead of hydroxyurea in children with SCD. There is a lack of high-quality research in the care of children with SCD, and therefore a call for action is needed.

The role of hydroxyurea in decreasing the occurrence of vasso-occulusive crisis in pediatric patients with sickle cell disease at King Saud Medical City in Riyadh, Saudi Arabia

OBJECTIVES

To measure the incidence of vaso-occlusive crises (VOC) and the role of hydroxyurea (HU) in reducing VOC in sickle cell anemia  patients being treated at a large tertiary care setting in Kingdom of Saudi Arabia (KSA). The secondary objective of this study is to observe the gradual improvement in laboratory data (white blood cell [WBC], platelets, mean corpuscular volume [MCV], hemoglobin [Hgb], HgbF) following regular use of HU. Methods: Clinical effectiveness of HU was evaluated in a large pediatric population using a retrospective cohort, non-interventional, pre-post treatment study designed to control disease severity selection bias. The cohort included children with SCA (sickle cell (SS), sickle-beta thalassemia) at King Saud Medical City, Riyadh, KSA, who initiated HU between January 2012 and June 2017. For each patient healthcare utilization, laboratory values, and clinical outcomes were observed for an equal duration of time pre and post hydroxyurea. Results: Out of 416 SCD patients, 128 children with SCD who initiated HU, of them 82 met the eligibility criteria. After initiation of HU, there was significant reduction in both VOC (80%) and length of stay (LOS) (73%). Significant increase in Hgb (13%), MCV (10%), and HgbF (28%) and significant decrease in WBC (28%) was observed. Only the mean platelet count decreased by 3% with a p greater than 0.05. Conclusion: Hydroxyurea treatment significantly decreased episodes of VOC and LOS, it also led to reductions in hospitalizations and significant improvement in complete blood count indices.

Sickle Cell Disease and Infections in High- and Low-Income Countries

Infections, especially pneumococcal septicemia, meningitis, and Salmonella osteomyelitis, are a major cause of morbidity and mortality in patients with sickle cell disease (SCD). SCD increased susceptibility to infection, while infection leads to SCD-specific pathophysiological changes. The risk of infectious complications is highest in children with a palpable spleen before six months of age. Functional splenectomy, the results of repeated splenic infarctions, appears to be a severe host-defense defect. Infection is the leading cause of death, particularly in less developed countries. Defective host-defense mechanisms enhance the risk of pneumococcal complications. Susceptibility to Salmonella infections can be explained at least in part by a similar mechanism. In high-income countries, the efficacy of the pneumococcal vaccine has been demonstrated in this disease. A decreased in infection incidence has been noted in SCD patients treated prophylactically with daily oral penicillin. Studies in low-income countries suggest the involvement of a different spectrum of etiological agents.

Hydroxycarbamide adherence and cumulative dose associated with hospital readmission in sickle cell disease: a 6-year population-based cohort study

Sickle cell disease (SCD) is a congenital haemoglobinopathy that causes frequent acute care/emergency room visits and hospital admissions for affected individuals. Evidence from population-based studies demonstrating the role of hydroxycarbamide (HC, also termed hydroxyurea) in reducing hospital readmission rates is limited. Our objective was to describe the use of HC and its association with acute care utilization and readmission rates using a large, nationally-representative US health insurance claims database over a 6-year period between 2009 and 2014. We identified 20 721 SCD-related inpatient and acute care encounters. Patients had been exposed to HC within 6 months prior to admission in 4263 (21%) of SCD-related admission events. HC use was more common among children aged 10-17 years and young adults aged 18-29 years. HC was associated with lower 30-day all-cause readmission rates in adults treated with average daily doses ≥1 g (odds ratio [OR], 0·72, 95% confidence interval [CI] 0·52-0·99) and doses of 0·5-1 g (OR, 0·73, 95% CI 0·57-0·93), compared to HC treatment with average daily doses of <0·5 g; adherence to HC with proportion of days covered of ≥0·80 was also associated with significantly lower 30-day all-cause readmission risks (OR, 0·59, 95% CI 0·41-0·84). Optimal therapeutic dosing and adherence to HC treatment significantly reduces 30-day readmissions among patients with SCD.

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.

Developing guidelines in low-income and middle-income countries: lessons from Kenya

There are few examples of sustained nationally organised, evidence-informed clinical guidelines development processes in Sub-Saharan Africa. We describe the evolution of efforts from 2005 to 2015 to support evidence-informed decision making to guide admission hospital care practices in Kenya. The approach to conduct reviews, present evidence, and structure and promote transparency of consensus-based procedures for making recommendations improved over four distinct rounds of policy making. Efforts to engage important voices extended from government and academia initially to include multiple professional associations, regulators and practitioners. More than 100 people have been engaged in the decision-making process; an increasing number outside the research team has contributed to the conduct of systematic reviews, and 31 clinical policy recommendations has been developed. Recommendations were incorporated into clinical guideline booklets that have been widely disseminated with a popular knowledge and skills training course. Both helped translate evidence into practice. We contend that these efforts have helped improve the use of evidence to inform policy. The systematic reviews, Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approaches and evidence to decision-making process are well understood by clinicians, and the process has helped create a broad community engaged in evidence translation together with a social or professional norm to use evidence in paediatric care in Kenya. Specific sustained efforts should be made to support capacity and evidence-based decision making in other African settings and clinical disciplines.

Hydroxycarbamine: from an Old Drug Used in Malignant Hemopathies to a Current Standard in Sickle Cell Disease

While hydroxycarbamide (hydroxyurea, HU) has less and fewer indications in malignant hemopathies, it represents the only widely used drug which modifies sickle cell disease pathogenesis. Clinical experience with HU for patients with sickle cell disease has been accumulated over the past 25 years in Western countries. The review of the literature provides increasing support for safety and efficacy in both children and adults for reducing acute vaso-occlusive events including pain episodes and acute chest syndrome. No increased incidence of leukemia and teratogenicity was demonstrated. HU has become the standard-of-care for sickle cell anemia but remains underused. Barriers to its use should be identified and overcome.

Sickle Cell Disease in Sub-Saharan Africa

In Africa, at least 240,000 children are born each year with sickle cell disease. Historically, in the absence of newborn screening and appropriate treatment, most such children died undiagnosed in early childhood. However, with increasing awareness of the condition and economic and epidemiologic transition, increasing numbers are surviving. Greater investments in basic and applied research in the African context, and increased sensitization or African ministries of health regarding the importance of this condition, could make a substantial difference to the lives and livelihoods of millions of people living with sickle cell disease on the continent and their families.

Sickle cell disease

INTRODUCTION

Sickle cell disease causes chronic haemolytic anaemia, dactylitis, and painful acute crises. It also increases the risk of stroke, organ damage, bacterial infections, and complications of blood transfusion. In sub-Saharan Africa, up to one third of adults are carriers of the defective sickle cell gene, and 1% to 2% of babies are born with the disease.

METHODS AND OUTCOMES

We conducted a systematic overview, aiming to answer the following clinical question: What are the effects of pharmaceutical interventions to prevent sickle cell crisis and other acute complications in people with sickle cell disease? We searched: Medline, Embase, The Cochrane Library, and other important databases up to January 2015 (Clinical Evidence overviews are updated periodically; please check our website for the most up-to-date version of this overview).

RESULTS

At this update, searching of electronic databases retrieved 369 studies. After deduplication and removal of conference abstracts, 136 records were screened for inclusion in the overview. Appraisal of titles and abstracts led to the exclusion of 99 studies and the further review of 37 full publications. Of the 37 full articles evaluated, three already included systematic reviews were updated, two systematic reviews, two RCTs, and one subsequent RCT were added at this update. We performed a GRADE evaluation for 12 PICO combinations.

CONCLUSIONS

In this systematic overview, we categorised the efficacy for five interventions based on information about the effectiveness and safety of antibiotic prophylaxis in children aged under 5 years, antibiotic prophylaxis in children aged 5 years or older, hydroxyurea, malaria chemoprophylaxis, and pneumococcal vaccines.

Hospitalization Events among Children and Adolescents with Sickle Cell Disease in Basra, Iraq

Objectives. Despite improvements in the management of sickle cell disease (SCD), many patients still experience disease-related complications requiring hospitalizations. The objectives of this study were to identify causes of hospitalization among these patients and factors associated with the length of hospital stay (LOS) and readmission. Methods. Data from 160 patients (<14 years old) with SCD who were admitted to the Basra Maternity and Children's Hospital from the first of January 2012 through July 2012 were analyzed. Results. The main causes of hospitalization were acute painful crises (73.84%), infections (9.28%), acute chest syndrome (8.02%), and acute splenic sequestration crisis (6.32%). The mean LOS was 4.34 ± 2.85 days. The LOS for patients on hydroxyurea (3.41 ± 2.64 days) was shorter than that for patients who were not (4.59 ± 2.86 days), P < 0.05. The readmission rate (23.1%) was significantly higher among patients with frequent hospitalizations in the previous year (OR 9.352, 95% CI 2.011–43.49), asthma symptoms (OR 4.225, 95% CI 1.125–15.862), and opioid use (OR 6.588, 95% CI 1.104–30.336). Patients on hydroxyurea were less likely to be readmitted (OR 0.082, 95% CI 0.10–0.663). Conclusions. There is a relatively high readmission rate among patients with SCD in Basra. The use of hydroxyurea significantly decreases the LOS and readmission rate.

Hydroxyurea use in prevention of stroke recurrence in children with sickle cell disease in a developing country: A cost effectiveness analysis

We undertook a cost effectiveness analysis (CEA) of hydroxyurea (HU) in preventing stroke recurrence and/or death. We followed 43 children with sickle cell disease from 2000 to 2009 after having a first clinical stroke, of whom 10 opted for HU therapy. HU use led to decreased stroke recurrence and death without significantly increasing the annual cost of care per patient (J$83,250 vs. J$76,901, P = 0.491). The incremental cost effectiveness ratio (ICER) for prevention of stroke recurrence amounted to J$169,238 (US$1,900), while that for death prevention equalled J$635,843 (US$7,140). HU may be recommended when safe and affordable transfusion therapy is not feasible.

Hashimoto's thyroiditis and acute chest syndrome revealing sickle cell anemia in a 32 years female patient

Sickle cell anemia results from a single amino acid substitution in the gene encoding the β-globin subunit. Polymerization of deoxygenated sickle hemoglobin leads to decreased deformability of red blood cells. Hashimoto's thyroiditis is a common thyroid disease now recognized as an auto-immune thyroid disorder, it is usually thought to be haemolytic autoimmune anemia. We report the case of a 32 years old women admitted for chest pain and haemolysis anemia in which Hashimoto's thyroiditis and sickle cell anemia were found. In our observation the patient is a young woman whose examination did not show signs of goitre but the analysis of thyroid function tests performed before an auto-immune hemolytic anemia (confirmed by a high level of unconjugated bilirubin and a Coombs test positive for IgG) has found thyroid stimulating hormone (TSH) and positive thyroid antibody at rates in excess of 4.5 times their normal value. In the same period, as the hemolytic anemia, and before the atypical chest pain and anguish they generated in the patient, the search for hemoglobinopathies was made despite the absence of a family history of haematological disease or painful attacks in childhood. Patient electrophoresis's led to research similar cases in the family. The mother was the first to be analyzed with ultimately diagnosed with sickle cell trait have previously been ignored. This case would be a form with few symptoms because the patient does not describe painful crises in childhood or adolescence.