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

A prospective study of 58 patients with sickle cell disease (SCD) by transcranial Doppler sonography (TCD) included both MRI and MRA in patients over 7 years of age and those with abnormal TCD. Arteriography was performed in cases where a stenosis was suspected on TCD. Middle cerebral artery (MCA) and basilar artery (BA) velocities were significantly higher in the sickle cell hemoglobin SS group than in the hemoglobin SC group. Patients with a MCA mean velocity of over 1.90 m/s had stenoses found by arteriography. Patients with unilaterally undetectable MCA flow had experienced a stroke and MCA thrombosis was confirmed at MRA and arteriography. We concluded that TCD is valuable in detecting arterial stenosis in SCD and will lead to consideration of these patients for intensive therapy, such as bone marrow transplantation (BMT) or transfusion regimes.
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PMID:Detection of cerebrovascular disease in patients with sickle cell disease using transcranial Doppler sonography: correlation with MRI, MRA and conventional angiography. 857 7

This study evaluates the MR appearance of the kidney in diffuse renal parenchymal diseases, using precontrast, and immediate and delayed postgadolinium chelate (Gd), spoiled gradient echo (SGE), and pre- and post-Gd, T1-weighted, fat-suppressed spin-echo MR images to determine if characteristic findings exist for various types of renal disease. One hundred twenty-one patients with renal disease underwent MRI. Underlying diagnoses included: (a) glomerular disease (GD), (b) tubulointerstitial disease (TID), (c) microvascular disease (MVD), (d) ischemic nephropathy (INP), (e) obstructive nephropathy (ON), (f) infectious renal disease (IRD), (g) sickle cell disease (SCD), (h) renal cortical necrosis (CN), and (i) renal insufficiency of unknown etiology (UE). MR examinations of 22 patients with normal kidneys (NK) were evaluated as a control group. The presence of corticomedullary differentiation (CMD) demonstrated strong inverse correlation with serum creatinine concentration (SCr) (r = -.568, P < .001). Mean thickness of the renal cortex was 8.4 and 7.8 mm in patients with NK and Gd, respectively. The mean cortical thickness in patients with MVD, TID/Chemo, INP, and ON was 5.2, 5.6, 5.5, and 4.3 mm, respectively, significantly thinner than the renal cortex in the NK and GD groups (P < .01). Irregularity of the renal cortex was more frequent in MVD (60.9%), IRD (62.5%), ON (55.6%), and TID/other (53.8%) than in GD (3.8%) and NK (0%) (P < .01). Diffuse high SI of the entire medulla on delayed postcontrast images was observed in 25 (20.7%) of the patients with renal disease and none of the NK group. Although no pathognomonic features were found, certain findings were observed that may correlate with the etiology of the kidney disease and, therefore, assist in the differential diagnosis of renal parenchymal disease.
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PMID:MR findings in diffuse renal parenchymal disease. 885 18

Stroke occurs in 7-8% of children with Sickle Cell Disease (Hb SS) and is a major cause of morbidity. Rates of recurrence have been reduced from 46-90% to less than 10% through chronic blood transfusions. Prevention of first stroke, however, would be preferable because even one stroke can cause irreversible brain injury. Transcranial Doppler (TCD) ultrasound can detect arterial blood flow rates associated with subsequent stroke risk. By combining TCD screening and a potentially effective treatment, first stroke may be prevented. The Stroke Prevention Trial in Sickle Cell Anemia (STOP) is the first stroke prevention trial in Hb SS and the first randomized, controlled use of transfusion in Hb SS. This multi-center trial is designed to test whether reducing sickle hemoglobin to 30% or less with periodic blood transfusions will reduce first-time stroke by at least 70% compared to standard care. Primary endpoints will be clinically evident symptoms of cerebral infarction with consistent findings on Magnetic Resonance Imaging and Angiography (MRI/MRA) or symptomatic intracranial hemorrhage. Secondary endpoints will be asymptomatic brain lesions detected by MRI in brain areas not involved in primary endpoints. The design calls for a 6-month start-up interval, 18 months of TCD screening and randomization, and observation for stroke from entry through month 54. Key features of the trial are standardized TCD and MRI/MRA protocols interpreted blindly, and blinded adjudication of endpoints. The sample size (60 per treatment group) is based on prospective data relating TCD velocity to risk of stroke. A time-averaged mean velocity of > or = 200 cm/sec is associated with a 46% risk of cerebral infarction over 39 months. The sample size is sufficient to detect 70% reduction in the primary endpoint at 90% power. This trial will determine if transfusion is effective in the primary prevention of stroke. Secondary aims may further the understanding of the effects of transfusion on the brain and guide future research into cerebrovascular disease in Hb SS.
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PMID:Stroke prevention trial in sickle cell anemia. 949 71

Conventional MRI (cMRI) has shown that brain abnormalities without clinical stroke can manifest in patients with sickle cell disease (SCD). We used quantitative MRI (qMRI) and psychometric testing to determine whether brain abnormalities can also be present in patients with SCD who appear normal on cMRI. Patients 4 years of age and older with no clinical evidence of stroke were stratified by cMRI as normal (n = 17) or abnormal (n = 13). Spin-lattice relaxation time (T1) of gray and white matter structures was measured by the precise and accurate inversion recovery (PAIR) qMRI method. Patient cognitive ability was assessed with a standard psychometric instrument (WISC-III or WISC-R). In all 30 patients with SCD, qMRI T1 was lower than in 24 age- and race-matched controls, in cortical gray matter (P < .0006) and caudate (P < .0009), as well as in the ratio of gray-to-white matter T1 (P < .008). In the 17 patients who were shown to be normal by cMRI, qMRI T1 was still lower than in controls, in both cortical gray matter (P < .02) and caudate (P < .004). Histograms of voxel T1 show that the proportion of voxels with T1 values intermediate between gray and white matter (ie, consistent with encephalomalacia) was 9% higher than controls in patients shown to be normal by cMRI (P < .05) and 15% higher than controls in patients shown to be abnormal by cMRI (P < .0005). The full scale intelligence quotient (FSIQ) of all patients with SCD was 75, compared to the FSIQ of 88 in a historical control group of patient siblings (P < .001). The FSIQ of patients shown to be normal by cMRI was 79, significantly lower than the FSIQ of patient siblings (P < .04). The FSIQ of 71 in patients shown to be abnormal by cMRI was significantly lower than both the patient siblings (P < .005) and the patients shown to be normal by cMRI (P < .04). Patients shown to be abnormal by cMRI scored lower than patients shown to be normal by cMRI, specifically on the subtests of vocabulary (P = .003) and information (P = .03). Cognitive impairment is thus significant, even in patients with SCD who were shown to be normal by cMRI, suggesting that cMRI may be insensitive to subtle neurologic damage that can be detected by qMRI. Because cognitive impairment can occur in children normal by cMRI, our findings imply that prophylactic therapy may be needed earlier in the course of SCD to mitigate neurologic damage.
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PMID:Quantitative MRI of the brain in children with sickle cell disease reveals abnormalities unseen by conventional MRI. 962 65

Intracranial or spinal epidural hematomas are almost always of post-traumatic origin, and rarely related to rupture of a dural vascular malformation or a hemostasis disorder. We report a case of spontaneous cerebral epidural hematoma observed in a young girl with homozygous sickle cell disease. After analysis of post-operative cerebral MRI, showing skull bone infarction inside and around the bone flap, it was considered that the skull bone infarction could be responsible for a diploic venous thrombosis with subsequent "spontaneous" epidural hematoma.
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PMID:[Uncommon etiology of extradural hematoma]. 969 94

This study examined the cognitive manifestations of frontal-lobe infarction in a population of children with sickle cell disease (SCD). Forty-one patients with SCD underwent MRI. Five patients with stroke symptoms had large infarcts encroaching on the tissue of the frontal lobes. Four patients without symptoms had smaller frontal-lobe infarcts. The patients with stroke were significantly impaired on measures of intelligence, memory, and frontal-lobe function (Wisconsin Card Sorting Test, WCST) compared with both the patients with normal MRI scans (N=30) and a group of sibling controls (N=15), who did not differ from each other. Patients with covert infarction obtained scores on the intelligence tests and the WCST that fell in between those of the stroke patients and the other two groups. This trend toward impairment suggests that patients with covert infarction are at similar risk for cognitive deficits to those with stroke.
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PMID:Cognitive deficits associated with frontal-lobe infarction in children with sickle cell disease. 974 6

Since 1988, 34 pediatric patients with severe sickle cell disease have received bone marrow transplantation (BMT) from HLA-identical siblings in France. After 1992, documentation of the favorable effect of hydroxyurea therapy on the frequency of vasoocclusive crisis (VOC) left a history of stroke (n = 16) as the main indication for BMT. Among patients treated by genoidentical BMT, 85% were cured and 9% died. All deaths were due to severe graft-versus-host disease. The rejection rate fell from 25% to 5% after addition of ATG to the conditioning regimen. BMT reversed some sickle cell disease-related abnormalities: splenic function improved and some cases of osteonecrosis showed a favorable course. Fifteen of 16 patients with a history of stroke showed no stroke recurrence after BMT, and arterial stenoses improved. BMT should be offered to sickle cell anemia patients with a history of stroke if a genoidentical donor is available. To prevent stroke-related residual impairment and transfusion-related complications, BMT should be considered early in patients with Doppler or MRI evidence of silent stroke associated with cognitive function impairment, failure to respond to hydroxyurea therapy (frequent VOCs, severe anemia and thrombocytosis, multifocal osteonecrosis), or polyerythroalloimmunization. Storage of frozen of cord blood samples from siblings should be considered.
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PMID:[Results and current indications of bone marrow allograft in sickle cell disease]. 1008 81

Nearly 25% of patients with sickle cell disease (SCD) experience central nervous system morbidity involving both large and small vessel disease. Optimal imaging methods for determining the extent of ischemia are not known. Positron emission tomography (PET) has the unique ability to show tissue function as well as structure. Reports concerning patients with non-SCD neurodegenerative disorders suggest PET may be useful in determining prognosis. We compared magnetic resonance imaging, magnetic resonance angiography, and neuropsychological testing with PET prospectively. Six patients with SCD and a history of stroke, aged 10 to 28, were enrolled. PET studies were performed on an ECAT HR 47 scanner (Siemens/CTI, Knoxville, TN) using 18-F-fluorodeoxyglucose as a tracer. PET interpretations were conducted in blinded fashion. MRI studies found two patients with only small vessel disease and four with both large and small vessel disease. In two of four subjects with large vessel disease, PET showed a corresponding metabolic abnormality and also identified an area of hypometabolism extending beyond the anatomical lesion as shown by MRI. PET did not demonstrate an abnormality corresponding with small vessel disease. Detailed neuropsychological testing demonstrated cognitive dysfunction in all cases. For some patients, PET may add sensitivity in detecting impaired metabolism in the area surrounding a major vessel infarct. However, the technique does not appear to be generally useful in characterizing small watershed or deep white matter infarcts. Larger studies, to include control subjects and carefully selected untransfused SCD patients, are needed. A combination of conventional imaging and neuropsychological testing remains the preferred evaluation for most SCD patients with neurologic symptoms.
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PMID:Role of positron emission tomography in determining the extent of CNS ischemia in patients with sickle cell disease. 1020 99

Neurological complications, especially stroke, have long been recognized in sickle cell disease. Advances in care have increased the life expectancy of such patients, and recent information has better established the epidemiology of stroke. Prevention of stroke in children has been established in a clinical trial. Silent brain lesions revealed by MRI are common and are associated with impairments of cognitive function. Transfusion remains the primary mode of prevention and treatment for stroke, although interest is increasing in hydroxyurea; however, there are no data regarding its efficacy.
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PMID:Stroke prevention in sickle cell disease. 1069 96

A case of paraplegia due to a thoracic epidural abscess in a 6-year-old black girl with sickle cell anemia is reported. MRI and CT scan showed abnormalities involving T6 vertebra which were consistent with osteomyelitis. A laminotomy, associated to antibiotic administration, permitted rapid neurological improvement. Although cultures were negative, the infection was probably due to salmonellae. Salmonellosis is a well-known complication in children with sickle cell disease but spinal localization is unusual. Its pathogenesis is unclear but immunological abnormalities associated to vascular obstructions by abnormal blood red cells have been advocated. The underlying etiology of vertebral abnormalities in these children is difficult to determine, but early diagnosis with modern investigations, as CT scan and MRI, is crucial to promptly begin therapy for osteomyelitis, minimizing the risk of spinal cord compression.
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PMID:[Vertebral osteomyelitis with epidural abscess in a child with sickle cell disease]. 1079 Jun 44


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