H. K:son Blomquist

A community-based prospective incidence study of epileptic seizures in children

During a 20‐month period, an attempt was made to find all children with unprovoked non‐febrile seizures. The first attendance and incidence rates were 95 and 89/100 000, respectively, in the age group 0–15 years. These figures are lower than those found 10 years earlier in the same area. The highest incidence was during the first year of life and there was a higher proportion of girls (male: female ratio 1:1.4). Generalized seizures dominated in the first year of life. The incidence of benign childhood epilepsy with centro‐temporal spikes was 10.7/100 000 and was the most common epilepsy syndrome found. The incidence of partial seizures increased with age up to the age of 10 yeqars. One in 10 children had a history of febrile convulsions.

Fragile site X chromosomes and X-linked mental retardation in severely retarded boys in a northern Swedish county. A prevalence study

In an unselected series of 96 severely mentally retarded boys (IQ < 50) born 1959–70 in a northern Swedish county, six had a fragile site on the distal end of the X chromosome (FraXq 28). The prevalence of the fragile X syndrome in severely retarded boys was 6 %. Next to trisomy 21, this fragile X syndrome appears to be the most common single cause of severe mental retardation in boys.

A Prospective Incidence Study of Febrile Convulsions

ABSTRACT. A prospective epidemiological study of febrile convulsions (FC) was performed during a 20‐month period. 128 children with FCs were identified. The annual first attendance rate and annual incidence rate were 500/100 000 and 460/100 000 respectively, in the age group 0–4 years. The cumulative incidence was 4.1%. FCs were more common among boys, with a male to female ratio of 1.72 to 1. The median and mean age for first FC was for boys 16 and 19.9 months respectively, and for girls 18 and 19.7 months respectively. During an average follow‐up period of 20 months, 18% had another FC and 10% had two or more FCs. 8.6% had an initial complicated FC. Four children had FCs within two weeks after being vaccinated by combined vaccine against morbilli, rubella and parotitis. Three of these had earlier had an FC.

Familial X-linked mental retardation and fragile X chromosomes in two Swedish families

X‐linked mental retardation (MR) associated with a fragile X chromosome was found in two Swedish families. The fragile X chromosome was demonstrated in 5/5 boys with mental retardation. Clinical data on four of these boys are presented. In one of the families, the mental retardation was associated with macro‐orchidism, large hands and large, folded ears. In the other family, macro‐orchidism was not seen, possibly because the boys were younger. Fragile site X chromosomes were also seen in three obligate carriers. A summary of earlier published cases of X‐linked MR associated with the fragile X chromosome is given.

Pre- and Perinatal Factors in Febrile Convulsions

Forsgren, L., Sidenvall, R., Blomquist, H. K:son, Heijbel, J. and Nyström, L. (Departments of Neurology, Paediatrics and Epidemiology and Health Care Research, University Hospital, Umeå, Sweden). Acta Paediatr Scand 80: 218, 1991.

Calcification of intervertebral discs in childhood.

Fifteen cases of intervertebral disc calcifications have been diagnosed in Umeå during a period of 14 years. In the literature up to now about 100 cases of intervertebral disc calcification have been reported. Our findings suggest that these calcifications are not as rare as has been stated. There are both symptomatic and silent cases. When present the clinical symptoms comprise local painin the neck, limitation of spinal movements and sometimes fever and the condition may simulate meningitis. The radiological findings are pathognomonic. The disc calcifications are most frequently found in boys especially in the cervical region. The etiology is unknown. The symptoms appear when the calcification, for some unknown reason, resorbs or herniates. Neurological symptoms are rare. The treatment is symptomatic and the clinical course self-limiting with complete recovery within a few weeks.

Evaluation of treatment in typical absence seizures. The roles of long-term EEG monitoring and ethosuximide.

ABSTRACT. Eleven children with typical absence seizures were studied clinically and by repeated 24‐h EEGs with portable cassette tape recorder before and during anticonvulsant treatment. The history, the observation of seizures and the amount of spike‐and‐wave activity (episodes >3 sec) were studied in relation to the plasma levels. The EEG revealed spike‐and‐wave episodes, considered as seizures, in a higher frequency than the number of absences reported by the parents. Twenty‐four hour EEG recording was however not superior to long term observation by relatives in establishing freedom from absences. The drug primary used was ethosuximide. Eight of eleven children responded completely on this drug, i.e. no absences observed and EEG was normalized. Of two children in whom the therapy was changed to sodium valproate, one responded completely and one partly. The relation between the ethosuximide dosage given and the plasma concentration level was good. Two cases responded at low plasma levels (<200 μmol/1). Tonic‐clonic seizures occurred in 3/11 children.

Tay or IBIDS Syndrome: A Case with Growth and Mental Retardation, Congenital Ichthyosis and Brittle Hair

ABSTRACT. A new, Swedish case with Tay or IBIDS syndrome is presented. The boy had growth and mental retardation, congenital ichthyosis and brittle hair. He was the only child in an uncle–niece marriage. The boy suffered recurrent infections and died at the age of 3 years from pneumonia. Clinical data on 15 cases are presented from a study of the literature.

Microcephaly, Mental Retardation and Chromosomal Aberrations in a Girl Following Radiation Therapy During Late Fetal Life

A human foetus was heavily irradiated in the thirtieth to the thirty-third week due to carcinoma of the uterine cervix of the mother. Irradiation after 20 weeks of pregnancy is thought not to produce severe abnormalities. However, the child showed microcephaly, mental retardation, stunted growth, microphthalmus, retinal degeneration, cataract and defective dentition. Cytogenetically the frequencies of both chromatid and chromosome breaks were increased.

An incident case-referent study of epileptic seizures children: Genetic and socioeconomic factors

Abstract In a prospective incident community-based case-referent study, 51 children with onset of unprovoked epileptic seizures after the neonatal period were compared with 89 age- and sex-matched referents with regard to genetic and socioeconomic factors. Epilepsy was more common in first-degree relatives of cases [odds ratio (OR) = 11.6; 95% confidence interval (CI) = 2.2; 61.1]. The proportion of cases with a positive family history of epilepsy was also higher in cases than referents (OR = 12.6, CI=2.3, 69.7 with epilepsy in first-degree relatives and OR=10.4, CI=3.8, 28.7 with epilepsy in any type of relative). The proportion of cases with febrile convulsions in relatives was higher than in referents (OR = 4.3, CI=1.6, 11.7). More cases than referents (OR = 12.4, CI=2.2, 70.1) had had a head trauma of moderate degree 6 months preceding onset of seizures. Regarding family characteristics, the risk was decreased by level of education for both father and mother (test for trend, p = 0.04). The risk for seizures was increased by number of siblings (test for trend p = 0.004). Finally, there was a tendency to increased risk with increased age of father and mother at birth of case/referents (test for trend p = 0.09 and 0.30, respectively).