Primary hemorrhagic stroke in children with sickle cell disease is associated with recent transfusion and use of corticosteroids

New Horizons in Emergency Department Management of Pediatric Sickle Cell Disease

ABSTRACT

Sickle cell disease (SCD) is an important topic for emergency medicine audiences because complications of the disease account for a large proportion of hematologic emergencies that are seen in the emergency department each year. Early recognition and aggressive management of emergency complications of SCD can help to reduce the morbidity and mortality associated with this disease. Although the treatment recommendations for some complications of SCD are based on expert opinion, there has been advancement in the understanding of the pathogenesis of the disease and evidence regarding the treatment options available for managing acute complications. This continuing medical education article will provide a summary of the clinical manifestation and management of the most common acute complications of SCD: infection, vaso-occlusive episode, acute chest syndrome, splenic sequestration, stroke, and priapism.

Multi-center retrospective study of children with sickle cell disease admitted to pediatric intensive care units in the United States

Data on outcomes and interventions for children with sickle cell disease (SCD) admitted to a pediatric intensive care units (PICU) are unknown. We provide the first comprehensive multi-center report on PICU interventions associated with death, the need for invasive respiratory support or stroke among critically ill children with SCD. We collected retrospective multi-center cohort data from January 1, 2012 to December 31, 2019 utilizing the Virtual Pediatric Systems, LLC database. We identified 3388 unique children with SCD, accounting for a total of 5264 PICU admissions from 138 PICUs. The overall mortality rate for the PICU admissions cohort was 1.8% (95/5264 PICU admissions, 95/3388 [2.8%] of all unique patients), the rate of needing of needing Invasive Respiratory Support (IRS, a composite category of exposure) was 21.3% (872/4093 PICU admissions with complete data) and the overall rate of stroke (ischemic or hemorrhagic) was 12.5% (657/5264 PICU admissions). In multivariable analysis adjusting for admission age category, sex, race/ethnicity, PRISM-3 score at admission, exposure to IRS, quartile of unit volume of patients with SCD, and patient origin, admitted children who needed invasive respiratory support (IRS) had higher adjusted odds ratios for mortality (adjusted odds ratio [aOR], 19.72; 95% confidence interval [CI] 8.98-43.29; p < 0.001), although admitted children > 2 years old had decreased aOR for needing IRS (aOR 0.25-0.62; 95% CI 0.16-0.94; p < 0.001-0.025). By contrast, admitted children > 2 years old had a strikingly increased aOR for stroke (aOR 7.57-16.32; 95% CI 2.25-52.15; p < 0.001). These groups may represent PICU-specific subsets of patients with SCD who are at higher risk for more serious illness and should deserve early consideration for referral to a pediatric institution providing comprehensive care for patients with SCD.

Risk of vaso-occlusive episodes in patients with sickle cell disease exposed to systemic corticosteroids: a comprehensive review

INTRODUCTION

Sickle cell disease (SCD) is the most frequent inherited disorder in the world. It is caused by a single amino acid mutation on the beta-globin chain, which lead to red blood cell deformation, haemolysis, and chronic inflammation. Clinical consequences are vaso-occlusives crisis, acute chest syndrome, thrombosis, infection, and chronic endothelial injury.

AREAS COVERED

Corticosteroids are an old therapeutic class, that are inexpensive and widely available, which can be administered in different forms. Their adverse effects are numerous and well-known. This class could appear to be useful in SCD treatment due to its anti-inflammatory effect. Moreover, corticosteroids remain an essential therapeutic class for many indications, besides SCD. Although specific adverse effects of corticosteroids have been suspected in SCD patients for decades, recent papers has reported strong evidence of specific and severe adverse effects in this population. Based on a literature review, we will discuss pathophysiological considerations, consequences, and practical use of corticosteroids in SCD.

EXPERT OPINION

High corticosteroid doses, for any indication , induce vaso-occlusive crises, acute chest syndrome, and re-hospitalization in patients with SCD. There is no evidence of any benefits of corticosteroid use in the SCD acute events. Prevention by hydroxyurea and/or red blood cell transfusion or exchange should be discussed when corticosteroid use is indispensable.

Blood pressure in children with sickle cell disease is higher than in the general pediatric population

Background

Sickle cell disease (SCD) is associated with an increased risk of cardiovascular disease that may be due to a variety of possible risk factors, including abnormal blood pressure. Blood pressure (BP) of children and adolescents with SCD has been reported to be lower compared to the BP of the general pediatric population.

Methods

To confirm this prior observation, we compared reference BP values for children with SCD with reference BP values of the general pediatric population. We hypothesized that children with SCD do not have lower BPs than children without SCD.

Results

Systolic BP differed for both males and females, over the different age groups between pediatric subjects with and without SCD. Systolic BP was higher in children with SCD, in both obese and non-obese populations. Diastolic BP did not differ between the groups.

Conclusions

Our analysis demonstrated that systolic BP values are indeed higher in children with SCD than in the general pediatric population. This finding is consistent with the most recent literature showing abnormal BP patterns in the SCD pediatric population utilizing 24-hour BP monitoring devices. This is an important step for recognizing abnormal BP as a risk factor for cardio- and neurovascular events in SCD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12887-022-03584-9.

Multisystem Inflammatory Syndrome in a Pediatric Patient With Sickle Cell Disease and COVID-19: A Case Report

To this day, there are limited data about the effects and management of coronavirus disease infection in pediatric patients with sickle cell disease. We present the management and successful clinical course of an 8-year-old female with homozygous sickle cell disease (SS) and severe acute chest syndrome secondary to coronavirus disease 2019 infection, complicated by cortical vein thrombosis.

A case series of hemorrhagic neurological complications of sickle cell disease: Multiple faces of an underestimated problem!

Sickle cell disease (SCD) is a group of hemoglobinopathies that vary in severity, the most severe form, homozygous sickle cell anemia, is more commonly associated with neurologic complications. These are attributed to the vaso-occlusion and micro-obstruction in the circulation of the central nervous system. The incidence of various neurologic complications in SCD ranges from 6% to 30% in various series. The commonly reported in literature include silent cerebral infarction (SCI), ischemic stroke, transient ischemic attacks (TIAs), headaches, seizures and neurocognitive impairment. However, hemorrhagic complications like subarachnoid hemorrhage (SAH), hemorrhagic stroke, extradural and subdural hematomas, especially in absence of trauma are rarely thought of. We report three uncommon spontaneous hemorrhagic manifestations of sickle cell anemia – one case of parenchymal (intracerebral) bleed who presented with acute onset of parkinsonism and two cases of extradural hematoma (EDH) of which one patient had recurrent EDH at the same site which is hitherto not reported in the literature.

Epidemiology of Stroke in Sickle Cell Disease

Sickle cell disease is the most common cause of stroke in childhood, both ischaemic and haemorrhagic, and it also affects adults with the condition. Without any screening or preventative treatment, the incidence appears to fall within the range 0.5 to 0.9 per 100 patient years of observation. Newborn screening with Penicillin prophylaxis and vaccination leading to reduced bacterial infection may have reduced the incidence, alongside increasing hydroxyurea prescription. Transcranial Doppler screening and prophylactic chronic transfusion for at least an initial year has reduced the incidence of stroke by up to 10-fold in children with time averaged mean of the maximum velocity >200 cm/s. Hydroxyurea also appears to reduce the incidence of first stroke to a similar extent in the same group but the optimal dose remains controversial. The prevention of haemorrhagic stroke at all ages and ischaemic stroke in adults has not yet received the same degree of attention. Although there are fewer studies, silent cerebral infarction on magnetic resonance imaging (MRI), and other neurological conditions, including headache, epilepsy and cognitive dysfunction, are also more prevalent in sickle cell disease compared with age matched controls. Clinical, neuropsychological and quantitative MRI screening may prove useful for understanding epidemiology and aetiology.

Bleeding in patients with sickle cell disease: a population-based study

Bleeding is a known complication of sickle cell disease (SCD) and includes hemorrhagic stroke, hematuria, and vitreous hemorrhage. However, the incidence of bleeding events in patients with SCD has not been well described. We present a retrospective, population-based study examining the cumulative incidence of bleeding in 6423 patients with SCD from 1991 to 2014. We also studied risk factors associated with bleeding and the effects of bleeding on mortality, using Cox proportional hazards regression models. We used California emergency department and hospitalization databases to identify patients with SCD with intracranial hemorrhage, gastrointestinal (GI) bleeding, hemophthalmos, gross hematuria, epistaxis, menorrhagia, and other bleeding events. The cumulative incidence of any first bleeding event at age 40 years was 21% (95% confidence interval [CI], 19.8%-22.3%), increasing with age to 41% by age 60 years (95% CI, 38.8%-43.1%). The majority of bleeding events were GI (41.6%), particularly from the upper GI tract. A higher bleeding risk was associated with increased frequency of hospitalization (hazard ratio [HR], 2.16; 95% CI, 1.93-2.42), venous thromboembolism 180 days before bleeding event (HR, 4.24; 95% CI, 2.86-6.28), osteonecrosis of the femoral head (HR, 1.25; 95% CI, 1.08-1.46), and ischemic stroke (HR, 1.65; 95% CI, 1.20-2.26). Bleeding was also associated with a twofold increased risk for death (HR, 2.09; 95% CI, 1.82-2.41) adjusted for other SCD-related complications. Our novel finding of a high incidence of bleeding in patients with SCD, particularly from the upper GI tract, suggests that patients with SCD may be predisposed to bleeding, with possible etiologies including increased use of nonsteroidal anti-inflammatory drugs, mucosal infarction from vascular occlusion by sickled red blood cells, and increased stress ulceration from frequent hospitalization.

Hypertension and childhood stroke

Cerebrovascular disease (stroke) is one of the ten leading causes of death in children and adolescents. Multiple etiologies, from arteriopathies to prothrombic states, can cause stroke in youth. In adult stroke, hypertension has been shown to be the single most important modifiable risk factor. Although hypertension has not been strongly identified as a risk factor in childhood stroke to date, there is preliminary evidence that suggests that hypertension may also be associated with stroke in children. In this review, we summarize the literature that may link hypertension to stroke in the young. We have identified a series of barriers and limitations in the fields of pediatric hypertension and pediatric neurology that might explain why hypertension has been overlooked in childhood stroke. We suggest that hypertension may be a relevant risk factor that, alone or in combination with other multiple factors, contributes to the development of stroke in children. Currently, there are no consensus guidelines for the management of post-stroke hypertension in children. Thus, we recommend that blood pressure be assessed carefully in every child presenting with acute stroke in order to better understand the effects of hypertension in the development and the outcome of childhood stroke. We suggest a treatment algorithm to help practitioners manage hypertension after a stroke.

Reversible Cerebral Vasoconstriction Syndrome and Sickle Cell Disease: A Case Report

Reversible cerebral vasoconstriction syndrome (RCVS), is rare in the pediatric population and is characterized by severe headaches and other neurologic symptoms. We present a case of RCVS occurring concomitantly with posterior reversible encephalopathy syndrome in an 8-year-old African American child with sickle cell disease (HbSS). Imaging studies including computed tomography, magnetic resonance imaging and cerebral angiography of the brain showed acute hemorrhagic stroke and a beaded appearance of peripheral cerebral vessels. In this report, we focus on the typical features of RCVS and discuss the underlying risk factors that may increase the risk in patients with HbSS disease.

Vascular Instability and Neurological Morbidity in Sickle Cell Disease: An Integrative Framework

It is well-established that patients with sickle cell disease (SCD) are at substantial risk of neurological complications, including overt and silent stroke, microstructural injury, and cognitive difficulties. Yet the underlying mechanisms remain poorly understood, partly because findings have largely been considered in isolation. Here, we review mechanistic pathways for which there is accumulating evidence and propose an integrative systems-biology framework for understanding neurological risk. Drawing upon work from other vascular beds in SCD, as well as the wider stroke literature, we propose that macro-circulatory hyper-perfusion, regions of relative micro-circulatory hypo-perfusion, and an exhaustion of cerebral reserve mechanisms, together lead to a state of cerebral vascular instability. We suggest that in this state, tissue oxygen supply is fragile and easily perturbed by changes in clinical condition, with the potential for stroke and/or microstructural injury if metabolic demand exceeds tissue oxygenation. This framework brings together recent developments in the field, highlights outstanding questions, and offers a first step toward a linking pathophysiological explanation of neurological risk that may help inform future screening and treatment strategies.

A physicians survey assessing management of pulmonary airway involvement in sickle cell disease

BACKGROUND

Airway involvement in patients with sickle cell disease (SCD) involves recurrent episodes of acute chest syndrome (ACS), co-existent asthma, lower airway obstruction (LAO), or airway hyper-responsiveness/ bronchodilator response (AHR/BDR). With increased recognition that sickle cell (SC) airway inflammation may be distinct from asthma, our aim was to study regional and individual practices among pediatric pulmonologists and elucidate the patient characteristics that determine the diagnosis of asthma or SC airway inflammation.

METHODS

A cross-sectional web-based survey including 6 case scenarios on diagnosis and management of pulmonary manifestations of pediatric SC airway disease was conducted. The case scenarios, combined different risk factors for airway inflammation: history of recurrent ACS, atopy, family history of asthma, LAO, or AHR/BDR, with possible responses including - diagnosis of asthma, SC airway inflammation, both or neither.

RESULTS

Of the 130 responses, 83 were complete. "Asthma" was diagnosed when LAO (OR, 7.96 [4.28, 14.79]; p < 0.001), family history of asthma (OR 18.88 [5.87, 60.7]; p < 0.001), and atopy (OR 3.19 [1.74, 5.8]; p < 0.001) were present. "SC airway inflammation" was diagnosed when ACS (OR 3.95 [2.08, 7.51]; p < 0.001), and restrictive pattern on PFT (OR 3.75 [2.3, 6.09]; p < 0.001) were present in the scenarios. Regardless of the diagnosis, there was a high likelihood of initiating or stepping up inhaled corticosteroid as compared to prescribing montelukast.

CONCLUSION

There is variability in the diagnosis and management of SC airway inflammation among pediatric pulmonologists. This study highlights the need for consensus guidelines to improve management of SC airway inflammation.

Spontaneous Epidural Hemorrhage in Sickle Cell Disease, Are They All the Same? A Case Report and Comprehensive Review of the Literature

Trauma to the skull causing injury to the middle meningeal artery, middle meningeal vein, or dural venous sinuses is responsible for most cases of epidural hemorrhage (EDH). Spontaneous EDH is a rare entity in clinical practice. Common causes include sinusitis, coagulation abnormalities, dural metastasis, and Langerhans cell histiocytosis. Isolated nontraumatic EDH is an exceedingly rare complication of sickle cell disease (SCD). We report a case of spontaneous EDH in a patient with SCD and review the world literature regarding this rare entity. A 20-year-old African American female with sickle cell disease presented with vaso-occlusive crisis. About 24 hours after hospital admission, the patient had sudden deterioration of her mental status. An emergent CT scan of the head revealed a large right-sided frontoparietal epidural hematoma with midline shift, subfalcine, and uncal herniation. The patient underwent emergent hematoma evacuation but died 24 hours after surgery.

Transcranial Doppler and Magnetic Resonance in Tanzanian Children With Sickle Cell Disease

Supplemental Digital Content is available in the text.

Background and Purpose—

We determined prevalences of neurological complications, vascular abnormality, and infarction in Tanzanian children with sickle cell disease.

Methods—

Children with sickle cell disease were consecutively enrolled for transcranial Doppler; those with slightly elevated (>150 cm/s), low (<50 cm/s) or absent cerebral blood flow velocity (CBFv) were invited for brain magnetic resonance imaging and magnetic resonance angiography.

Results—

Of 200 children (median age 9; range 6–13 years; 105 [2.5%] boys), 21 (11%) and 15 (8%) had previous seizures and unilateral weakness, respectively. Twenty-eight (14%) had elevated and 39 (20%) had low/absent CBFv, all associated with lower hemoglobin level, but not higher indirect bilirubin level. On multivariable analysis, CBFv>150 cm/s was associated with frequent painful crises and low hemoglobin level. Absent/low CBFv was associated with low hemoglobin level and history of unilateral weakness. In 49 out of 67 children with low/absent/elevated transcranial Doppler undergoing magnetic resonance imaging, 43% had infarction, whereas 24 out of 48 (50%) magnetic resonance angiographies were abnormal. One had hemorrhagic infarction; none had microbleeds. Posterior circulation infarcts occurred in 14%. Of 11 children with previous seizure undergoing magnetic resonance imaging, 10 (91%) had infarction (5 silent) compared with 11 out of 38 (29%) of the remainder (P=0.003). Of 7 children with clinical stroke, 2 had recurrent stroke and 3 died; 4 out of 5 had absent CBFv. Of 193 without stroke, 1 died and 1 had a stroke; both had absent CBFv.

Conclusions—

In one-third of Tanzanian children with sickle cell disease, CBFv is outside the normal range, associated with frequent painful crises and low hemoglobin level, but not hemolysis. Half have abnormal magnetic resonance angiography. African children with sickle cell disease should be evaluated with transcranial Doppler; those with low/absent/elevated CBFv should undergo magnetic resonance imaging/magnetic resonance angiography.

Nonaneurysmal Subarachnoid Hemorrhage in Sickle Cell Disease: Description of a Case and a Review of the Literature

Descriptions of the natural history of cerebrovascular complications of sickle cell disease (SCD) characterize ischemic stroke as common during childhood and hemorrhagic stroke as more common in adulthood. Childhood ischemic stroke is attributed to vasculopathy with moyamoya syndrome. Hemorrhagic stroke is commonly attributed to aneurysms accompanying HbSS cerebral vasculopathy in SCD. However, a growing body of literature highlights multiple contributing factors to hemorrhagic stroke in children. Primary hemorrhagic stroke is one of the most devastating neurological complications of SCD. We describe the case of an 18-year-old female affected by HbSS genotype SCD presenting with reversible cerebral vasoconstriction syndrome (RCVS) as well as features of posterior reversible encephalopathy syndrome and convexity subarachnoid hemorrhage (SAH) after transfusion of red blood cells. We reviewed the existing literature dealing with SCD, blood transfusion, and hemorrhagic strokes. To our knowledge, this case presentation is unique with convexity SAH predominantly attributable to a RCVS spectrum disorder occurring in the setting of a recent blood transfusion in an adolescent female with SCD. As this case illustrates, neurological deterioration accompanied by intracranial hemorrhage in children and young adults with SCD after blood transfusion should raise suspicion for RCVS as part of a complex cerebral vasculopathy. A better understanding of the risk factors leading to hemorrhagic stroke may help prevent this severe complication in subjects with SCD. Neuroimaging including angiography in these subjects may enable prompt diagnosis and management.

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.

Acute Hemorrhagic Encephalitis Responding to Combined Decompressive Craniectomy, Intravenous Immunoglobulin, and Corticosteroid Therapies: Association with Novel RANBP2 Variant

Background

Acute hemorrhagic encephalomyelitis (AHEM) is considered as a rare form of acute disseminated encephalomyelitis characterized by fulminant encephalopathy with hemorrhagic necrosis and most often fatal outcome.

Objective

To report the association with Ran Binding Protein (RANBP2) gene variant and the response to decompressive craniectomy and high-dose intravenous methylprednisolone (IVMP) in life-threatening AHEM.

Design

Single case study.

Case report

A 6-year-old girl known to have sickle cell disease (SCD) presented an acquired demyelinating syndrome (ADS) with diplopia due to sudden unilateral fourth nerve palsy. She received five pulses of IVMP (30 mg/kg/day). Two weeks after steroid weaning, she developed right hemiplegia and coma. Brain magnetic resonance imaging showed a left frontal necrotico-hemorrhagic lesion and new multifocal areas of demyelination. She underwent decompressive craniotomy and evacuation of an ongoing left frontoparietal hemorrhage. Comprehensive investigations ruled out vascular and infectious process. The neurological deterioration stopped concomitantly with combined neurosurgical drainage of the hematoma, decompressive craniotomy, IVMP, and intravenous immunoglobulins (IVIG). She developed during the following months Crohn disease and sclerosing cholangitis. After 2-year follow-up, there was no new neurological manifestation. The patient still suffered right hemiplegia and aphasia, but was able to walk. Cognitive/behavioral abilities significantly recovered. A heterozygous novel rare missense variant (c.4993A>G, p.Lys1665Glu) was identified in RANBP2, a gene associated with acute necrotizing encephalopathy. RANBP2 is a protein playing an important role in the energy homeostasis of neuronal cells.

Conclusion

In any ADS occurring in the context of SCD and/or autoimmune condition, we recommend to slowly wean steroids and to closely monitor the patient after weaning to quickly treat any recurrence of neurological symptom with IVMP. This case report, in addition to others, stresses the likely efficacy of combined craniotomy, IVIG, and IVMP treatments in AHEM. RANBP2 mutations may sensitize the brain to inflammation and predispose to AHEM.

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.

Rheumatoid Arthritis in Sickle-Cell Population: Pathophysiologic Insights, Clinical Evaluation and Management

The advent of hydroxyurea and advanced medical care, including immunizations has led to improved survival among patients with Sickle Cell Disease (SCD). This prolonged survival however, introduces a chronic inflammatory disorder, Rheumatoid Arthritis (RA), which presents at a relatively older age and is rarely reported among SCD patients. In this review, we highlight the epidemiological association of SCD-RA and discuss the underlying common pathogenetic mechanisms, such as endothelial dysfunction, the role of inflammatory cytokines and oxidative stress. We also point to the difficulties in ascertaining the clinical diagnosis of RA in SCD patients. Finally, we provide rationale for therapeutic options available for RA and the challenges in the management of these patients with agents that are known to increase the risk of infection and immunosuppression such as steroids, disease modifying anti-rheumatic drugs and biologics.

Acute Chest Syndrome in Children with Sickle Cell Disease

Acute chest syndrome (ACS) is a frequent cause of acute lung disease in children with sickle cell disease (SCD). Patients may present with ACS or may develop this complication during the course of a hospitalization for acute vaso-occlusive crises (VOC). ACS is associated with prolonged hospitalization, increased risk of respiratory failure, and the potential for developing chronic lung disease. ACS in SCD is defined as the presence of fever and/or new respiratory symptoms accompanied by the presence of a new pulmonary infiltrate on chest X-ray. The spectrum of clinical manifestations can range from mild respiratory illness to acute respiratory distress syndrome. The presence of severe hypoxemia is a useful predictor of severity and outcome. The etiology of ACS is often multifactorial. One of the proposed mechanisms involves increased adhesion of sickle red cells to pulmonary microvasculature in the presence of hypoxia. Other commonly associated etiologies include infection, pulmonary fat embolism, and infarction. Infection is a common cause in children, whereas adults usually present with pain crises. Several risk factors have been identified in children to be associated with increased incidence of ACS. These include younger age, severe SCD genotypes (SS or Sβ⁰ thalassemia), lower fetal hemoglobin concentrations, higher steady-state hemoglobin levels, higher steady-state white blood cell counts, history of asthma, and tobacco smoke exposure. Opiate overdose and resulting hypoventilation can also trigger ACS. Prompt diagnosis and management with intravenous fluids, analgesics, aggressive incentive spirometry, supplemental oxygen or respiratory support, antibiotics, and transfusion therapy, are key to the prevention of clinical deterioration. Bronchodilators should be considered if there is history of asthma or in the presence of acute bronchospasm. Treatment with hydroxyurea should be considered for prevention of recurrent episodes. This review evaluates the etiology, pathophysiology, risk factors, clinical presentation of ACS, and preventive and treatment strategies for effective management of ACS.

Stroke and Hypertension in Children and Adolescents

Hypertension is the single most important modifiable risk factor for adult stroke. Stroke mortality has significantly decreased over the last 5 decades; this decline has been mainly associated to improved blood pressure control. Though much less prevalent than in adults, stroke is an increasingly recognized cause of morbidity and mortality in children. Although hypertension has not been strongly identified as a risk factor in childhood stroke yet, there is preliminary evidence that suggests that elevated blood pressure may be associated with stroke in children. This review summarizes the literature that may link elevated blood pressure to the development of childhood ischemic and hemorrhagic stroke. The authors suggest that elevated blood pressure may be a significant risk factor that, alone or in combination with other multiple risk factors, leads to the development of stroke in childhood. It is therefore recommend that blood pressure be measured and assessed carefully in every child presenting with acute stroke.

Sickle Cell Disease and Stroke: Diagnosis and Management

Both adult and pediatric patients with sickle cell disease face a higher risk of stroke than the general population. Given the different underlying pathophysiology predisposing these patients to stroke, providers should be aware of differences in guidelines for stroke management. This paper reviews diagnostic considerations and recommendations during the evaluation and acute management of patients with sickle cell disease presenting with stroke, focusing on recent updates in the literature. Given the high recurrence rate of stroke in these patients, secondary prevention and curative measures will also be reviewed.

Lectin-like oxidized low-density lipoprotein receptor (LOX-1) in sickle cell disease vasculopathy

Lectin-like oxidized low-density lipoprotein (LDL) receptor-1 (LOX-1) is an endothelial receptor for oxidized LDL. Increased expression of LOX-1 has been demonstrated in atherosclerotic lesions and diabetic vasculopathy. In this study, we investigate the expression of LOX-1 receptor in sickle cell disease (SCD) vasculopathy. Expression of LOX-1 in brain vascular endothelium is markedly increased and LOX-1 gene expression is upregulated in cultured human brain microvascular endothelial cells by incubation with SCD erythrocytes. Also, the level of circulating soluble LOX-1 concentration is elevated in the plasma of SCD patients. Increased LOX-1 expression in endothelial cells is potentially involved in the pathogenesis of SCD vasculopathy. Soluble LOX-1 concentration in SCD may provide a novel biomarker for risk stratification of sickle cell vascular complications.

Central nervous system complications and management in sickle cell disease

With advances in brain imaging and completion of randomized clinical trials (RCTs) for primary and secondary stroke prevention, the natural history of central nervous system (CNS) complications in sickle cell disease (SCD) is evolving. In order of current prevalence, the primary CNS complications include silent cerebral infarcts (39% by 18 years), headache (both acute and chronic: 36% in children with sickle cell anemia [SCA]), ischemic stroke (as low as 1% in children with SCA with effective screening and prophylaxis, but ∼11% in children with SCA without screening), and hemorrhagic stroke in children and adults with SCA (3% and 10%, respectively). In high-income countries, RCTs (Stroke Prevention in Sickle Cell Anemia [STOP], STOP II) have demonstrated that regular blood transfusion therapy (typically monthly) achieves primary stroke prevention in children with SCA and high transcranial Doppler (TCD) velocities; after at least a year, hydroxycarbamide may be substituted (TCD With Transfusions Changing to Hydroxyurea [TWiTCH]). Also in high-income countries, RCTs have demonstrated that regular blood transfusion is the optimal current therapy for secondary prevention of infarcts for children with SCA and strokes (Stroke With Transfusions Changing to Hydroxyurea [SWiTCH]) or silent cerebral infarcts (Silent Infarct Transfusion [SIT] Trial). For adults with SCD, CNS complications continue to be a major cause of morbidity and mortality, with no evidence-based strategy for prevention.

HbSC Disease and Spontaneous Epidural Hematoma with Kernohan's Notch Phenomena

Spontaneous (nontraumatic) acute epidural hematoma is a rare and poorly understood complication of sickle cell disease. A 19-year-old African American male with hemoglobin SC disease (HbSC) presented with generalized body aches and was managed for acute painful crisis. During his hospital stay he developed rapid deterioration of his mental status and computed topography revealed a spontaneous massive epidural hematoma with mass effect and midline shift with Kernohan's notch phenomena for which urgent craniotomy and evacuation was done. We report the first case of HbSC disease associated with catastrophic epidural hematoma progressing to transtentorial herniation and Kernohan's notch phenomena within few hours with rapid clinical deterioration. The etiopathogenesis and the rare presentation are discussed in detail in this case report.

How I treat and manage strokes in sickle cell disease

Neurologic complications are a major cause of morbidity and mortality in sickle cell disease (SCD). In children with sickle cell anemia, routine use of transcranial Doppler screening, coupled with regular blood transfusion therapy, has decreased the prevalence of overt stroke from ∼11% to 1%. Limited evidence is available to guide acute and chronic management of individuals with SCD and strokes. Current management strategies are based primarily on single arm clinical trials and observational studies, coupled with principles of neurology and hematology. Initial management of a focal neurologic deficit includes evaluation by a multidisciplinary team (a hematologist, neurologist, neuroradiologist, and transfusion medicine specialist); prompt neuro-imaging and an initial blood transfusion (simple followed immediately by an exchange transfusion or only exchange transfusion) is recommended if the hemoglobin is >4 gm/dL and <10 gm/dL. Standard therapy for secondary prevention of strokes and silent cerebral infarcts includes regular blood transfusion therapy and in selected cases, hematopoietic stem cell transplantation. A critical component of the medical care following an infarct is cognitive and physical rehabilitation. We will discuss our strategy of acute and long-term management of strokes in SCD.

Spontaneous Intracranial Extradural Hematoma in Sickle Cell Disease

Spontaneous extradural hematoma is rare in patients with sickle cell disease. We report a clinical case of a 19-year-old young man with sickle cell anemia who presented a sickle cell crisis complicated by the development of multiple acute extradural and subgaleal hematomas that had not been treated surgically. We discuss the physiopathology of this event. Although it is rare, clinicians should be aware of this phenomenon as part of a spectrum of neurologic complications in these patients.

Unruptured Intracranial Aneurysms in Children With Sickle Cell Disease

BACKGROUND:

Intracranial aneurysms (IAs) are rare in the general pediatric population and account for &lt;2% of all cerebral aneurysms. Only 7 children with sickle hemoglobinopathy and IAs have been reported, the majority of which were discovered after rupture.

OBJECTIVE:

To report the prevalence of unruptured IAs in a selected population of children with sickle cell disease (SCD) and to describe the aneurysm morphology, hematologic characteristics, and management in this patient population.

METHODS:

A retrospective review of the electronic database for all children with SCD who underwent brain magnetic resonance imaging or angiography from January 2002 to August 2013 at a single institution was performed. Records were reviewed for IA, age, sex, sickle cell genotype, neurological symptoms, hematologic indexes, transcranial Doppler findings, and management.

RESULTS:

Five of 179 children (2.8%) with SCD imaged by brain magnetic resonance imaging or angiography were diagnosed with IAs. None presented with subarachnoid hemorrhage. Four patients (80%) had HbSS disease, and 1 patient had hemoglobin sickle cell HbSC disease. A total of 18 aneurysms were detected; the majority of patients had multiple aneurysms (80%) and bilateral involvement (60%).

CONCLUSION:

Children with SCD are at risk for developing multiple intracranial aneurysms, and a high index of suspicion must be maintained during the interpretation of routine magnetic resonance imaging or angiography of the brain.

Cerebral haemorrhagic risk in children with sickle-cell disease

AIM

To address risk of first or recurrent cerebral haemorrhage in children with sickle-cell disease (SCD) who are being managed with modern stroke prevention strategies.

METHOD

A systematically followed SCD paediatric cohort was retrospectively studied over a 9-year period. Haemorrhagic risk was defined as intracranial haemorrhage occurrence or intracranial aneurysm diagnosis during the study period. Ischaemic risk was defined as cerebrovascular ischaemic event occurrence or transcranial Doppler/magnetic resonance imaging hallmarks of ischaemic risk finding during the study period.

RESULTS

Among the 251 patients in the cohort, 36 patients were included in the ischaemic group. Seven patients were included in the haemorrhagic group, of which five also met the criteria for the ischaemic group. Age at first haemorrhagic symptom/hallmark of risk was older (10.4 vs 6.2 years old, p=0.036). Nine intracranial saccular aneurysms were found, mostly on the posterior circulation. Two patients had endovascular embolization.

INTERPRETATION

The ratio of ischaemic to haemorrhagic risk was not modified with modern management compared with historical series. Intracranial aneurysm in children with SCD had specific characteristics, close to intracranial aneurysms described in adults with SCD. Data favoured concurrent development of intracranial SCD-associated anterior stenosis and posterior dilation, suggesting common pathophysiology and management strategies.

Subarachnoid haemorrhage and cerebral vasculopathy in a child with sickle cell anaemia

Stroke in sickle cell anaemia (SCA) is either infarctive or haemorrhagic in nature. In childhood, over 75% of strokes in SCA are infarctive. We present an adolescent with SCA who developed hypertension at the age of 13, and was treated with lisinopril. Sixteen months later she was found in cardiorespiratory arrest and died on arrival in hospital. The last transcranial Doppler scan performed 6 months before her death and a brain MRI were reported normal. The autopsy discovered massive subarachnoid haemorrhage in association with vascular damage in the circle of Willis arteries. The case highlights a cause of haemorrhagic stroke, the first reported association between hypertension, SCA and a histopathologically proven cerebral vasculopathy. The difficulties in the management of haemorrhagic stroke and the poor outcome in SCA are discussed.

Wheezing symptoms and parental asthma are associated with a physician diagnosis of asthma in children with sickle cell anemia

OBJECTIVE

To identify factors associated with asthma associated with increased sickle cell anemia (SCA).

STUDY DESIGN

Children with SCA (N = 187; mean age 9.6 years, 48% male) were classified as having "asthma" based on parent report of physician diagnosis plus prescription of asthma medication (n = 53) or "no asthma" based on the absence of these features (n = 134). Pain and acute chest syndrome (ACS) events were collected prospectively.

RESULTS

Multiple variable logistic regression model identified 3 factors associated with asthma: parent with asthma (P = .006), wheezing causing shortness of breath (P = .001), and wheezing after exercise (P < .001). When ≥2 features were present, model sensitivity was 100%. When none of the features were present, model sensitivity was 0%. When only 1 feature was present, model sensitivity was also 0%, and presence of ≥2 of positive allergy skin tests, airway obstruction on spirometry, and bronchodilator responsiveness did not improve clinical utility. ACS incident rates were significantly higher in individuals with asthma than in those without asthma (incident rate ratio 2.21, CI 1.31-3.76), but pain rates were not (incident rate ratio 1.28, CI 0.78-2.10).

CONCLUSIONS

For children with SCA, having a parent with asthma and specific wheezing symptoms are the best features to distinguish those with and without parent report of a physician diagnosis of asthma and to identify those at higher risk for ACS events. The value of treatment for asthma in the prevention of SCA morbidity needs to be studied.

Wheezing in children with sickle cell disease

PURPOSE OF REVIEW

The purpose of this article is to provide a comprehensive review of wheezing in sickle cell disease (SCD), including epidemiology, pathophysiology, associations between wheezing and SCD morbidity and finally the clinical approach to evaluation and management of individuals with SCD who wheeze.

RECENT FINDINGS

Wheezing is common in SCD and in some individuals represents an intrinsic component of SCD-related lung disease rather than asthma. Emerging data suggest that, regardless of the cause, individuals with SCD and with recurrent wheezing are at increased risk for subsequent morbidity and premature mortality. We believe individuals who acutely wheeze and have respiratory symptoms should be managed with a beta agonist and short-term treatment of oral steroids, typically less than 3 days to attenuate rebound vaso-occlusive disease. For those who wheeze and have a history or examination associated with atopy, we consider asthma treatment and monitoring per National Heart, Lung and Blood Institute asthma guidelines.

SUMMARY

Wheezing in SCD should be treated aggressively both in the acute setting and with controller medications. Prospective SCD-specific clinical trials will be necessary to address whether anti-inflammatory asthma therapies (leukotriene antagonists, inhaled corticosteroids) can safely mitigate the sequelae of wheezing in SCD.

Sickle cell disease in children

Early identification of infants with sickle cell disease (SCD) by newborn screening, now universal in all 50 states in the US, has improved survival, mainly by preventing overwhelming sepsis with the early use of prophylactic penicillin. Routine transcranial Doppler screening with the institution of chronic transfusion decreases the risk of stroke from 10% to 1% in paediatric SCD patients. Hydroxyurea decreases the number and frequency of painful crises, acute chest syndromes and number of blood transfusions in children with SCD. Genetic research continues to be driven toward the prevention and ultimate cure of SCD before adulthood. This review focuses on clinical manifestations and therapeutic strategies for paediatric SCD as well as the evolving topic of gene-focused prevention and therapy.

Pulmonary complications of sickle cell disease

Sickle cell disease (SCD) is a common monogenetic disorder with high associated morbidity and mortality. The pulmonary complications of SCD are of particular importance, as acute chest syndrome and pulmonary hypertension have the highest associated mortality rates within this population. This article reviews the pathophysiology, diagnosis, and treatment of clinically significant pulmonary manifestations of SCD, including acute chest syndrome, asthma, and pulmonary hypertension in adult and pediatric patients. Clinicians should be vigilant in screening and treating such comorbidities to improve patient outcomes.

Asthma morbidity and treatment in children with sickle cell disease

Children with sickle cell disease (SCD) and a comorbid condition of asthma have increased numbers of vaso-occlusive pain and acute chest syndrome episodes, and all-cause mortality. When assessed systematically, asthma prevalence is probably similar among children with SCD when compared with the general African-American population. With increasing recognition of the importance of asthma in the management of SCD, hematologists must become familiar with asthma and develop a multidisciplinary approach, including early recognition, appropriate management and referral to asthma specialists.

Prospects for primary stroke prevention in children with sickle cell anaemia

This review will focus on the strengths and limitations associated with the current standard of care for primary prevention of ischaemic strokes in children with sickle cell anaemia (SCA) - transcranial Doppler ultrasound (TCD) screening followed by regular blood transfusion therapy when TCD measurement is above a threshold defined by a randomized clinical trial (RCT). The theoretical basis for potential alternative strategies for primary prevention of neurological injury in SCA is also discussed. These strategies will include, but will not be limited to: immunizations to prevent bacterial infections, particularly in low income countries; management of elevated blood pressure; and targeted strategies to increase baseline haemoglobin levels with therapies such as hyroxycarbamide or potentially definitive haematopoietic stem cell transplant.