Adolescent spinal muscular atrophy with calf hypertrophy and a deletion in the SMN gene.

Spinal muscular atrophy (SMA) is generally associated with proximal weakness and muscle wasting. An X-linked variant with calf hypertrophy has been reported. We describe a young man with SMA type 4 with prominent calf hypertrophy in whom DNA analysis showed a homozygous deletion of exons 7 and 8 in the telomeric copy of the survival motor neuron gene. Calf hypertrophy may be seen uncommonly in autosomally inherited SMA.

SEPN1: associated with congenital fiber-type disproportion and insulin resistance.

OBJECTIVE: Our first objective was to determine whether SEPN1 gene mutations are a cause of congenital fiber-type disproportion (CFTD), a rare form of congenital myopathy in which relative hypotrophy of type 1 (slow twitch) muscle fibers is the principal abnormality on histology. Second, we investigated an association between SEPN1-related myopathy and insulin resistance. METHODS: We sequenced SEPN1 in five unrelated CFTD patients with scoliosis and respiratory muscle weakness and screened an additional 22 CFTD patients for abnormalities in SEPN1 by Western blotting and restriction digest for the 943G-->A mutation. We performed oral glucose tolerance tests (OGTTs) in eight SEPN1-related myopathy patients. RESULTS: Two sisters with CFTD were homozygous for the 943G-->A SEPN1 mutation and had clinical features typical of previously reported patients with SEPN1-related myopathy. Five of eight SEPN1-related myopathy patients had abnormalities on OGTT suggestive of insulin resistance. INTERPRETATION: SEPN1 is the second genetic cause of CFTD and the first cause of autosomal recessive CFTD to be identified to our knowledge. CFTD is the fourth clinicopathological presentation that can be associated with mutations in SEPN1. Insulin resistance may be a specific, previously unrecognized aspect of SEPN1-related myopathy.

Subacute inflammatory demyelinating polyneuropathy in children.

Reported are five children with subacute demyelinating polyneuropathy. All patients had a monophasic disease, progressing over 4 to 8 weeks and characterized by predominantly motor features, areflexia, minimal or no cranial nerve abnormalities, no autonomic or respiratory involvement, elevated CSF protein, electrophysiologic evidence of demyelination, and good response to corticosteroids. A benign course with full recovery was the rule.

Neuropsychological outcome after acute disseminated encephalomyelitis: impact of age at illness onset.

Recovery from acute disseminated encephalomyelitis in childhood appears relatively uneventful, at least when looking at functional recovery parameters such as neurologic outcome. However, neuropsychology literature suggests that relatively transient illnesses affecting the central nervous system are associated with cognitive and social sequelae, particularly when the illness occurs during the preschool years. This study investigated the impact of timing of acute disseminated encephalomyelitis on intellectual, educational, and social functioning in children. Nineteen children (10 with acute disseminated encephalomyelitis before the age of 5 years), who had been admitted to the Royal Children's Hospital, Melbourne Australia, in the past 6 years underwent a brief neuropsychologic assessment. Performance was compared with 19 control subjects, stratified for age and socioeconomic status with the acute disseminated encephalomyelitis group. Children who sustained their illness before 5 years of age were particularly vulnerable to impairments in both cognitive and social domains. In particular, a higher incidence of severe behavioral and emotional problems was reported by parents of children who had experienced acute disseminated encephalomyelitis before 5 years of age. This finding suggests that there may be long-term complications in early childhood. A multidisciplinary approach to management post-illness is warranted in this age group.

Childhood chronic inflammatory demyelinating polyneuropathy with central nervous system demyelination resembling multiple sclerosis.

Central nervous system demyelination has been described in adults but not in children with chronic inflammatory demyelinating polyneuropathy. We describe a patient with clinical and electrophysiological features consistent with chronic inflammatory demyelinating polyneuropathy who presented at age 5 with an intramedullary spinal cord tumor-like lesion and at age 8, represented with cerebral and spinal demyelinating lesions. Her clinical course and magnetic resonance imaging features were atypical for multiphasic disseminated encephalomyelitis and indistinguishable from multiple sclerosis. To our knowledge, this association has not been previously described in the English literature in childhood.

Hemiconvulsion-hemiplegia-epilepsy syndrome: characteristic early magnetic resonance imaging findings.

We report three patients with hemiconvulsion-hemiplegia-epilepsy syndrome who presented acutely and were shown to have striking neuroimaging findings suggestive of diffuse cytotoxic edema confined to one hemisphere, including extensive diffusion-weighted imaging abnormalities in two cases. Two patients subsequently developed progressive and extensive atrophy of the involved hemisphere. These findings are consistent with earlier descriptions of the classic neuroradiologic features of this syndrome and are helpful in the differential diagnosis of acute infantile hemiplegia. Further, the findings support the previously proposed pathogenetic mechanism of neuronal injury caused by status epilepticus.