Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cerebrovascular accidents (CVA) are serious complications of sickle cell anemia (SS) in children. Factors that predispose children to this complication are not well established. In an effort to elucidate the risk factors associated with CVA in SS, we have determined the alpha-globin genotype and the beta(S) haplotype of children with this complication. Among 700 children with SS followed at Children's Hospital of Michigan, 41 (6%) are on chronic transfusions because of stroke due to cerebral infarction. The mean age of patients with CVA at the time of stroke was 5.6 +/- 3.2 years (mean +/- SD). The male/female ratio was 2/3. Only 8 of 41 patients (19.5%) had one alpha-gene deletion, compared to the reported prevalence of 30% in African-Americans. None of the patients had two alpha-gene deletions, and two (5%) had five alpha-genes. These findings are different than those in our adult patients with SS, where the prevalence of -alpha/-alpha and alphaalphaalpha/alphaalpha is 4% and <2%, respectively. Ten different beta(S)-haplotypes were detected in the patients studied. The majority of the patients (31%) were doubly heterozygous for the Ben/CAR haplotypes followed by Ben/Ben, Ben/Sen, and CAR/CAR haplotypes, respectively. The prevalence of these haplotypes, with the exception of the CAR/CAR haplotype, was higher in females than males. All the patients with CAR/CAR haplotype were males, had four alpha-genes, and ranked third in prevalence. Three patients were heterozygous for the Cameron haplotype. The Cameron and atypical haplotypes were more prevalent than reported in patients with SS at large. The data suggest that CVA in children seems to occur more frequently in females and in patients with certain beta(S) haplotype. alpha-Gene deletion seems to offer a protective effect against this complication. Neonates with four or more alpha-genes whose beta(S) haplotype is Ben/CAR, atypical, or CAR/CAR seem to be at a higher risk for CAV than other patients. A prospective study on a larger group of patients with or without CVA may clarify this issue.
 ...
PMID:Molecular characteristics of pediatric patients with sickle cell anemia and stroke. 1139 15

Cerebral infarction is a frequent, severe complication of sickle cell anaemia. During childhood, most strokes are due to infarction with the majority resulting from occlusion of the large cerebral arteries. Risk factors include transient ischaemic attacks, acute chest syndrome, severe anaemia and elevated blood pressure. Less certain is the association with leucocytosis, or protection provided by alpha-thalassaemia or fetal haemoglobin. Children who have one stroke are at significant risk for having subsequent events that can be substantially reduced by maintaining haemoglobin S below 30%. It has not yet been possible to identify individuals for whom transfusion can be safely stopped. Haemosiderosis is a consequence of intensive and long term transfusion therapy, which requires chelation with deferoxamine. Iron accumulation can be minimised using erythrocytapheresis but this is technically difficult in children, expensive and results in increased donor exposure. In addition to lesions associated with strokes, an additional 17% of patients can be shown to have clinically silent cerebral infarcts. Although these are termed 'silent', those affected have mild neuropsychological deficits. Their relationship to stroke or risk for recurrence is unknown. Transfusion therapy has been shown to provide primary stroke prevention for children who have elevated cerebral artery velocity. Finally, intracranial haemorrhages, more commonly found in adults, also affect children. Subarachnoid haemorrhage is frequently found to result from cerebral artery aneurysms. A condition that mimics the moyamoya syndrome radiographically, as well as for its risk of haemorrhage, can be found in children with partly occluded cerebral arteries either as a result of stroke or silent infarct.
 ...
PMID:Stroke in children with sickle cell anaemia: aetiology and treatment. 1143 87

Cerebral infarction in children may be the result of various disease processes, including emboli from intracardiac sources, paradoxical emboli from the venous system, sickle cell disease, cyanotic heart disease, vasculitis affecting the carotid or cerebral vascular system, vascular anomalies, and prothrombotic states. We present a previously healthy adolescent who presented with the acute onset of hemiparesis. Work-up revealed a dilated cardiomyopathy with a left ventricular mural thrombus as the etiology of his cerebrovascular event. Although dilated cardiomyopathy (DCM) may predispose to the development of a mural thrombus and subsequent embolic events, there are no previous reports in pediatric-aged patients of the development of an embolic event as the presenting manifestation of DCM. Further investigation of the etiology of the DCM led to the diagnosis of a pheochromocytoma. Congestive heart failure and DCM as the presenting sign of pheochromocytoma has likewise not been reported in a pediatric-aged patient. We review this unlikely sequence of events, the diagnostic evaluation of such patients, and treatment options.
 ...
PMID:Cerebrovascular event, dilated cardiomyopathy, and pheochromocytoma. 1186 37

Children with sickle cell anemia (SCA) carry a 200-fold increased risk for cerebral infarction. Stroke can be the result of small-vessel (SV) or large-vessel (LV) disease. However, it is unknown whether these subtypes result from the same pathophysiologic processes. Complete HLA genotyping was performed on 231 eligible children previously enrolled in the Cooperative Study of Sickle Cell Disease (CSSCD). Cerebral infarction on magnetic resonance imaging (MRI) was documented in 71 patients, and 160 patients had negative findings on MRI. Based on MRI/magnetic resonance angiography (MRA) findings, infarct size, and location, 36 patients were classified as having LV stroke and 35 as having SV stroke. When comparing the total MRI+ group with the MRI- group, HLA DPB1*0401 was associated with increased stroke risk (P =.01), whereas DPB1*1701 (P =.02) conferred protection from stroke. These DPB1 associations with stroke were attributed to the SV stroke group, in whom DPB1*0401 was associated with susceptibility (P =.003) and DPB1*1701 with protection from stroke (P =.06). In the LV stroke subgroup, HLA-A*0102 (P =.02) and -A*2612 (P =.007) conferred susceptibility, whereas -A*3301(P =.04) protected from stroke. These results suggest that specific HLA alleles influence stroke risk and appear to contribute differently to SV and LV stroke subtypes. The distinct HLA associations with SV and LV stroke suggest that different pathologic processes may be involved in the development of stroke in children with SCA. If these results are confirmed in a larger study, HLA type may serve as a useful marker for the early identification of SCA patients at high risk for stroke.
 ...
PMID:Distinct HLA associations by stroke subtype in children with sickle cell anemia. 1251 10

Cerebral infarcts occur in approximately 30% of children with sickle cell disease (SCD), but little information exists regarding remediation of associated cognitive deficits. The authors examined the benefits of training children with infarcts to use memory strategies. Six children with SCD-related infarcts received academic tutoring; three of these children received additional training in memory strategies (silent rehearsal to facilitate short-term memory and semantic organization to facilitate long-term memory). The performance of children receiving strategy training appeared to improve more than that of children receiving only tutoring. Memory in children with SCD-related infarcts may be enhanced through strategy training.
 ...
PMID:Memory strategy training in children with cerebral infarcts related to sickle cell disease. 1279 31

Stroke affects both motor and cognitive function in patients with sickle cell disease (SCD). Symptomatic stroke is associated with intimal disease of the large cerebral arteries. Silent stroke, defined as cerebral infarction in the absence of overt clinical neurologic symptoms, is often due to microinfarcts suggestive of microvascular disease. While the natural history of stroke in SCD is well described, the pathophysiology remains poorly understood and probably varies with the site of vascular injury. Increased red cell adhesion, oxidative injury of the vessel wall, inflammation, abnormal vasomotor tone regulation, and increased activity of the coagulation system all may contribute to cerebral vasopathology in SCD.
 ...
PMID:Pathophysiology of stroke in sickle cell disease. 1528 92

Cerebral infarction is a major cause of morbidity and mortality in children with sickle cell disease. Prevention of primary stroke might be feasible with a way to identify children at greatest risk. Transcranial Doppler (TCD) has been shown to be a noninvasive, reliable, inexpensive method of identifying children at highest risk for cerebral infarction. The pros and cons of imaging and non-imaging TCD techniques are discussed. The protocol for the stroke prevention trial in sickle cell anemia (STOP), including data acquisition and interpretation, is reviewed. Providing TCD to sickle cell patients can be a valuable service that results in a significant decrease in first stroke rates.
 ...
PMID:Screening children for sickle cell vasculopathy: guidelines for transcranial Doppler evaluation. 1570 3

Sickle cell disease (SCD) is a common form of hemoglobinopathy and is highly prevalent worldwide. Silent cerebral infarction, which represents infarction without clinical signs, is a risk factor for clinical stroke in patients with SCD. It is well known that silent infarction predisposes patients with SCD to overt stroke. The aim of the present study is to investigate the effect of silent infarction on neurological soft signs (NSS), which demonstrate subtle impairments in sensory integration, motor coordination and the sequencing of complex motor acts and to evaluate whether NSS can be used in clinical practice to evaluate the patients at risk of stroke in SCD patients with silent infarction. Fifty-nine SCD patients without any documented history of cerebrovascular accident and 28 healthy controls were included in this study. All the patients with SCD were evaluated with cerebral magnetic resonance imaging. We found that the NSS scores were significantly higher in patients with silent cerebral infarction than those in patients without silent infarction and control subjects (p < 0.05). Importantly, there was no significant difference in the NSS scores between the patients without silent infarction and control subjects. These results indicate that high NSS scores represnt an important finding for diagnosis of silent infarction in SCD patients. As silent infarction increases the risk for stroke in patients with SCD, NSS can be used to provide additional information in diagnosis of the patients with possible stroke risk during the course of SCD.
 ...
PMID:Neurological soft signs as the stroke risk in sickle cell disease. 1670 55

We present the findings in 14 paediatrics patients with SCA who had CT examination at the University College Hospital Ibadan on account of stroke between 1993 and 2000. There were 8 female and 6 male with a mean age of 11.25 years and SD of 3.66. Cerebral infarction was the most common finding occurring in 57% of the patients while intracerebral bleed was seen in 21%. Two patients had a mixed lesion and atrophy was seen in one patient. Five patients (36%) had their lesion on the right hemisphere while eight (57%) had their lesions on the left side. The frontal and parietal lobes were mainly affected. Prompt CT screening of the brain in a child with sickle cell anaemia who presents with symptoms and signs suggestive of stroke can help identify the particular type of lesion and this may influence mode of therapy given as well as prognosis
 ...
PMID:Computed tomographic pattern of stroke in children with sickle cell anaemia in Ibadan. 1674 33

We reviewed our records over a 15-year period to determine whether or not the impression that stroke complicating sickle cell disease was less common than reported in North America. Records of children aged 16 years and below with a diagnosis of stroke seen at the University College Hospital, Ibadan, Nigeria between 1988 and 2002 were examined. Thirty-nine such patients were identified but only 31 had detailed records available for study. Twenty-seven of these had sickle cell disease, 26 with haemoglobin genotype SS and 1 with Hb S+C. Sickle cell disease was therefore responsible for 87% of stroke seen in children at our centre. With an average clinic population of about 500 patients with sickle cell disease, the hospital frequency of stroke among these patients is estimated at 5.4%. The mean age of occurrence of the first stroke was 6.8 years ranging from 17 months to 11 years. Of the 7 patients who had CT scans of the brain done, 5 had evidence of cerebral infarction while 2 had intracerebral haemorrhage. While only 2 deaths occurred among the cases reviewed, morbidity was significant with only 6 patients achieving complete recovery. Recurrent stroke occurred after an average of 25.6 months in 8 of 13 patients who were followed up (61.5%). The incidence of stroke among African children with sickle cell disease appears to be not as high as reported in patients from North America.
 ...
PMID:Stroke in Nigerian children with sickle cell disease. 1674 40


<< Previous 1 2 3 4 5 6 Next >>