BACKGROUND Silent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). We tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular blood-transfusion therapy than among those who received standard care. METHODS In this randomized, single-blind clinical trial, we randomly assigned children with sickle cell anemia to receive regular blood transfusions (transfusion group) or standard care (observation group). Participants were between 5 and 15 years of age, with no history of stroke and with one or more silent cerebral infarcts on magnetic resonance imaging and a neurologic examination showing no abnormalities corresponding to these lesions. The primary end point was the recurrence of an infarct, defined as a stroke or a new or enlarged silent cerebral infarct. RESULTS A total of 196 children (mean age, 10 years) were randomly assigned to the observation or transfusion group and were followed for a median of 3 years. In the transfusion group, 6 of 99 children (6%) had an end-point event (1 had a stroke, and 5 had new or enlarged silent cerebral infarcts). In the observation group, 14 of 97 children (14%) had an end-point event (7 had strokes, and 7 had new or enlarged silent cerebral infarcts). The incidence of the primary end point in the transfusion and observation groups was 2.0 and 4.8 events, respectively, per 100 years at risk, corresponding to an incidence rate ratio of 0.41 (95% confidence interval, 0.12 to 0.99; P = 0.04). CONCLUSIONS Regular blood-transfusion therapy significantly reduced the incidence of the recurrence of cerebral infarct in children with sickle cell anemia. (Funded by the National Institute of Neurological Disorders and Stroke and others; Silent Cerebral Infarct Multi-Center Clinical Trial ClinicalTrials.gov number, NCT00072761, and Current Controlled Trials number, ISRCTN52713285.)

Brief training in coping skills followed by minimal therapist contact may lead to a range of benefits when children practice with their skills on a consistent basis.

In the phase I/II pediatric hydroxyurea safety trial (HUG-KIDS), school-aged children with sickle cell anemia receiving hydroxyurea at the maximally tolerated dose (MTD) had variable increases in the percentage of fetal hemoglobin (%HbF). To identify predictors of the HbF response to hydroxyurea therapy, baseline clinical and laboratory values (age, sex, hemoglobin concentration, %HbF, reticulocytes, white blood cell [WBC], platelets, and serum chemistries), as well as treatment variables (number of toxicities, noncompliance, MTD dose, and MTD blood counts) were analyzed in 53 HUG-KIDS children who achieved MTD. Baseline %HbF values (P ‫؍‬ .001), baseline hemoglobin concentration (P ‫؍‬ .01), MTD dose (P ‫؍‬ .02), and compliance (P ‫؍‬ .02) were significantly associated with a higher %HbF at MTD; in contrast, age, sex, number of toxicities, and other baseline hematologic parameters were not. After adjusting for variations in baseline %HbF, the baseline reticulocyte count (P ‫؍‬ .05) and baseline WBC count (P ‫؍‬ .05) were also significantly associated with a higher %HbF at MTD. Hydroxyurea-induced increases in the hemoglobin concentration and mean corpuscular volume (both higher absolute values at MTD and larger positive changes from baseline values), as well as hydroxyurea-induced decreases in reticulocytes and WBC count, were significantly associated with a higher %HbF at MTD. These data suggest that selected baseline laboratory parameters, a higher MTD dose with attention to compliance, and greater therapy-related changes in blood counts may predict the HbF response to hydroxyurea therapy for children with sickle cell anemia. The HbF response to hydroxyurea is variable and complex, however, and even children with IntroductionThe level of fetal hemoglobin (HbF) expression is one of the most important modifiers of disease expression for patients with sickle cell anemia. 1 The percentage of HbF (%HbF) influences both laboratory values and clinical features of children and adults with sickle cell anemia. For example, an elevated %HbF has been significantly associated with fewer painful vasoocclusive events, 2 fewer episodes of acute chest syndrome, 3 and reduced early mortality. 4,5 Pharmacologic enhancement of HbF expression has been accomplished by using myelosuppressive agents, cytokines, and short-chain fatty acids. [6][7][8] To date, however, the prototypic agent for increasing HbF expression is hydroxyurea, based on its ease of oral administration, modest toxicity profile, and rarity of serious side effects. A phase I/II trial of hydroxyurea for adults with sickle cell anemia demonstrated a significant increase in HbF expression, accompanied by a significant increase in hemoglobin concentration and significant decreases in reticulocytes, neutrophils, and platelets. 9 The Multicenter Study of Hydroxyurea (MSH), a doubleblinded, placebo-controlled phase III trial for adults with sickle cell anemia, demonstrated that hydroxyurea therapy significantly reduced the number of painful events, episodes of acute che...

The most common form of neurologic injury in sickle cell anemia (SCA) is silent cerebral infarction (SCI). In the Silent Cerebral Infarct Multi-Center Clinical Trial, we sought to identify risk factors associated with SCI. In this cross-sectional study, we evaluated the clinical history and baseline laboratory values and performed magnetic resonance imaging of the brain in participants with SCA (HbSS or HbS␤°thalassemia) between the ages of 5 and 15 years with no history of overt stroke or seizures. Neuroradiology and neurology committees adjudicated the presence of SCI. SCIs were diagnosed in 30.8% (251 of 814) participants who completed all evaluations and had valid data on all prespecified demographic and clinical covariates. The mean age of the participants was 9.1 years, with 413 males (50.7%). In a multivariable logistic regression analysis, lower baseline hemoglobin concentration (P < .001), higher baseline systolic blood pressure (P ‫؍‬ .018), and male sex (P ‫؍‬ .030) were statistically significantly associated with an increased risk of an SCI. Hemoglobin concentration and systolic blood pressure are risk factors for SCI in children with SCA and may be therapeutic targets for decreasing the risk of SCI. This study is registered at www.clinicaltrials.gov as #NCT00072761. IntroductionSilent cerebral infarcts (SCIs) have been recognized by neuroimaging in neurologically normal older adult populations since 1981 1 and were documented in sickle cell anemia (SCA) soon afterward. 2 As with overt stroke, SCIs represent a clinical finding that is common in older adults without SCD, but they appear during early childhood in persons with SCA. SCIs are defined as an MRI signal abnormality visible on 2 views on the T2-weighted images (axial and coronal) that must measure at least 3 mm in one dimension; further, the person deemed to have an SCI must have an absence of focal neurologic deficit compatible with the anatomic location of the brain lesion. 3 SCI is the most common form of neurologic injury among children with SCA, occurring in at least 27% before 6 years of life 4 and 37% by 14 years of life. 5 SCIs in children with SCA are associated with increased risk of future overt strokes and new or progressive SCIs. 6,7 In addition, children with SCA and SCI have been found to have poorer cognitive function The publication costs of this article were defrayed in part by page charge payment. Therefore, and solely to indicate this fact, this article is hereby marked ''advertisement'' in accordance with 18 USC section 1734. 3684BLOOD, 19 APRIL 2012 ⅐ VOLUME 119, NUMBER 16For personal use only. on March 28, 2019. by guest www.bloodjournal.org From than children with SCA with normal MRI of the brain 8-10 or sibling controls. 10,11 Clinical and laboratory risk factors for SCI have been evaluated only sparingly. In the most rigorous study to date, the investigators from the Cooperative Study for Sickle Cell Disease (CSSCD) described risk factors associated with SCI in 42 participants, comparing them with 188 controls with ...