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Biomedical subjects

R S Shalev

Publications and source records attributed to R S Shalev.

At least 19 recordsLinked to original sources
PubMed1995

Developmental dyscalculia and brain laterality.

The correlation between arithmetic dysfunction and brain laterality was studied in 25 children with developmental dyscalculia (DD). The children were tested on a standardized arithmetic battery and underwent a neurological and neuro-psychological evaluation. A diagnosis of left hemisphere dysfunction (n = 13) was based on right side soft neurological signs, performance IQ (PIQ) > verbal IQ (VIQ), dyslexia and intact visuo-spatial functions. The criteria for right hemisphere dysfunction (n = 12) were left body signs, VIQ > PIQ, impaired visuo-spatial functions and normal language skills. The groups were similar for age, gender, and socio-economic status. Our results showed that both groups scored more than 2 SD below the mean adjusted score on the arithmetic battery, but the left group was significantly worse in 3 areas: mastery of addition/subtraction, complex multiplication and division and visuo-spatial errors (p < 0.05). The data indicate that dysfunction of either hemisphere hampers arithmetic acquisition, but arithmetic impairment is more profound with left hemisphere dysfunction.

Adolescent↗
PubMed1995

Developmental right-hemisphere syndrome: clinical spectrum of the nonverbal learning disability.

We report the clinical characteristics of the developmental right-hemisphere syndrome (DRHS), a nonverbal learning disability, in 20 children (9 girls and 11 boys; mean age = 9.5 years) who also manifested attention-deficit/hyperactivity disorder (ADHD), severe graphomotor problems, and marked slowness of performance. Diagnostic criteria for this study included (a) emotional and interpersonal difficulties; (b) paralinguistic communication problems; (c) impaired visuospatial skills, verbal IQ > performance IQ, and verbal IQ > or = 85; and either (d) dyscalculia or (e) neurological signs on the left side of the body. In this group, verbal IQ was significantly higher than performance IQ (106.6 +/- 13.0 vs. 85.1 +/- 13.1, respectively, p < .01). Arithmetic was the lowest score among the verbal subtests (7.8 +/- 3.5, p < .01) and Geometrical Design was the lowest score among the performance subtests (5.8 +/- 1.7). Thirteen children had soft neurological signs on the left side of the body. ADHD was seen in all 20 children, marked slowness of performance in 16, and severe graphomotor problems in 18. The latter two features have not been previously described as part of DRHS.

Adolescent↗
PubMed1993

GPI Mount Scopus--a variant of glucosephosphate isomerase deficiency.

Glucosephosphate isomerase (GPI) deficiency is an unusual cause of hereditary nonspherocytic hemolytic anemia. The disease, inherited as an autosomal recessive disorder, is most often manifested by symptoms and signs of chronic hemolysis, ameliorated by splenectomy. We recently diagnosed GPI deficiency in a 23-year-old Ashkenazi Jewish man who displayed the typical clinical course of this disorder. The biophysical characteristics of the GPI variant are slow electrophoretic mobility, presence of only one of the two bands normally present, and extreme thermolability. To the best of our knowledge, this is the first report of GPI deficiency in a patient of Jewish descent, and we propose to designate this enzyme variant "GPI Mount Scopus".

Adult↗
PubMed1993

Intravenous high-dose gammaglobulins for intractable childhood epilepsy.

Immunological mechanisms have been implicated in the pathogenesis of epileptic seizures in some patients and in experimental animal models of epilepsy. A beneficial effect of high dose intravenous gammaglobulin (IVIG) has been demonstrated for some children with intractable epilepsy. In this study we treated 9 children ages 1.1-9.2 years (mean 5.0 years) with intractable epilepsy not responsive to conventional antiepileptic drugs (AEDs) and steroid therapy. Eight children had Lennox-Gastaut syndrome and 1 had complex partial seizures with secondary generalization. Each child received 3 doses of IVIG (200 mg/kg of polyvalent immunoglobulin) on Days 1, 15 and 36. Concomitant AEDs were not changed. Four children had complete remission, 3 had partial response with a more than 50% reduction in seizure frequency and 2 had no response. Onset of response varied from immediate to 7 months after the last injection. No toxicity was noted. Duration of remission was 9 months in 1 case. The other 3 cases have remained in remission to date with a follow up period of 22-26 months. We conclude that IVIG is a safe therapy which appears to be effective in some children with intractable seizures. Children with shorter duration of their seizure disorder (< 1 year) and relatively preserved cognitive function (IQ > 70) appear to have a more favorable response. Larger scale controlled trials are needed to determine the optimal timing and dosage, as well as to identify specific subgroups which may benefit most from IVIG treatment.

Child↗
PubMed1993

Developmental dyscalculia and medical assessment.

Developmental dyscalculia (DC) is a primary cognitive disorder of childhood manifested by disturbance of arithmetic ability. As an isolated learning disability (LD), it is usually treated by remedial education and not referred for further medical evaluation. We examined a group of 7 third-grade children with DC attending a mainstream school who had not progressed academically in spite of specific special education intervention. We were able to identify in all 7 children neurological conditions that had direct bearing on the children's cognitive disabilities and remedial programs. One child had petit mal seizures, another developmental Gerstmann syndrome, a third had dyslexia for numbers, and 4 children had attention deficit disorders without hyperactivity. Based on this experience, we suggest that the indications for medical or neurological assessment be broadened to include children who are not improving academically in spite of appropriate professional intervention.

Attention Deficit Disorder with Hyperactivity↗
PubMed1992

Striatal degeneration and spongy myelinopathy in glutaric acidemia.

The neuropathological findings in a 6 1/2-year-old boy with glutaric acidemia (GA) are described, and the pathology of 7 additional literature cases is briefly reviewed. Bilateral striatal degeneration and spongy change of the white matter were the salient features in this case and seem to represent the cardinal pathological features of the disease. Spongy myelinopathy was the result of intramyelinic vacuolation due to splitting of the myelin sheath along the intraperiod line, as illustrated here for the first time in GA. Based on morphological, biochemical and pharmacological data from humans and experimental animals, it is hypothesized that excitotoxin-mediated neuronal damage may account for the striatal degeneration, while toxic effect on myelin metabolism by the metabolic derangement of GA may explain the widespread white matter changes.

Amino Acid Metabolism, Inborn Errors↗
PubMed1992

Familial hypotonia of childhood caused by isolated 3-methylcrotonyl-coenzyme A carboxylase deficiency.

Hypotonia was the initial symptom in four siblings from a nonconsanguineous Tunisian-Jewish family. Plasma carnitine was severely deficient, and urinary organic acid analysis revealed increased excretion of 3-hydroxyisovaleric acid and 3-methylcrotonylglycine. 3-Methylcrotonyl-coenzyme A carboxylase activity was reduced in skin fibroblasts; pyruvate carboxylase and serum biotinidase activities were normal. We conclude that 3-methylcrotonyl-coenzyme A carboxylase deficiency should be added to the list of metabolic causes of familial hypotonia of childhood.

Carbon-Carbon Ligases↗
PubMed1989

Glutaric aciduria type I: enzymatic and neuroradiologic investigations of two kindreds.

Two kindreds with glutaric aciduria type I were investigated. Of 20 family members who underwent neurologic examination and organic acid analysis of urine, 18 had glutaryl-coenzyme A dehydrogenase (GDH) activity determined in cultured skin fibroblasts and 12 had computed tomographic brain scans. Six homozygotes were identified who had undetectable GDH activity and identical biochemical profiles (consisting of glutaric and 3-hydroxyglutaric aciduria, reduced serum carnitine concentrations, and frontotemporal atrophy). Serial computed tomographic brain scans of one homozygous infant demonstrated the sequential postnatal development of this atrophy during 3 years before the development of clinical manifestations. In three of the six homozygotes, including the father in one kindred, there were no clinical manifestations of glutaric aciduria type I. These findings raise questions about the value of prenatal diagnosis in predicting clinical manifestations in homozygous newborn infants.

Adult↗
PubMed1988

Developmental dyscalculia.

We conducted a neurobehavioral evaluation on eleven children with developmental dyscalculia in order to determine which aspects of arithmetic processes are affected in this disorder. Our results indicate that memorization of numerical facts in these children was poor or virtually non-existent and the ability to solve simple arithmetic exercises impaired. By contrast, comprehension and production of number functions were intact. Although all children had been referred for evaluation of selective deficits in arithmetic skills, they also displayed a mild degree of dyslexia, dysgraphia, anomia, and grapho-motor dysfunction. We conclude that cognitive mechanisms underlying arithmetic ability can be dissociated developmentally and suggest that remediation programs be designed only after detailed analyses of arithmetic and associated cognitive skills.

Adolescent↗
PubMed1987

Glutaric aciduria type I: clinical heterogeneity and neuroradiologic features.

We present four patients, two pairs of siblings, with glutaric aciduria type I (GA I). All four had undetectable glutaryl-CoA dehydrogenase activity on fibroblast culture and massive urinary excretion of glutaric acid. All had serum carnitine deficiency at time of diagnosis except one patient who was diagnosed neonatally. All had a unique pattern of frontotemporal atrophy on CT. Remarkably, in both sibling pairs, one child was asymptomatic. This suggests that the biochemical markers hitherto identified with GA I do not encompass the entire scope of the metabolic or enzymatic abnormalities. Alternatively, as yet unidentified mechanisms might spare or delay the destructive process.

Atrophy↗
PubMed1986

Valproic acid in neonatal status convulsivus.

Valproic acid infused rectally was successful in controlling seizures in two neonates who failed to respond to conventional anti-convulsive therapy. We suggest that this drug may be a useful adjuvant in difficult cases of status convulsivus in neonates.

Humans↗
PubMed1986

Gowers' sign in discitis in childhood.

Three cases of discitis in early childhood presented with acute refusal to walk or change in gait pattern without neurologic deficits. In all three, a Gowers' sign was observed, although none had muscular weakness. The diagnosis of discitis was confirmed by the characteristic radiographic findings on survey lumbosacral films and/or by a hot spot at the L3 level on technetium bone scan.

Child, Preschool↗
PubMed1986

Sleep patterns in the Lennox-Gastaut syndrome.

Serial polysomnograms were performed on 11 children with primary Lennox-Gastaut syndrome (LGS), 6 control children with other seizure disorders, and 12 who were developmentally normal. Five LGS children had abnormal polysomnograms with either complete absence or marked reduction of REM sleep; the other six LGS children had only a mild reduction of REM sleep. The percentage of REM in LGS children was less than in the controls with other seizure disorders (p less than 0.05) or the normal children (p less than 0.005). The scatter of REM percentages in LGS may imply heterogeneity of the syndrome, perhaps related to the severity of brainstem dysfunction or neurochemical derangement.

Adolescent↗