[Case of dentatorubral-pallidoluysian atrophy with onset of psychomotor retardation in infancy].

We report a patient with dentatorubral-pallidoluysian atrophy (DRPLA). She developed normally until the age of 6 month, when she could sit by herself. However, her psychomotor development was subsequently slow with gradual appearance of equilibrium disturbances and involuntary movements such as polymyoclonia and chorea. Her development deteriorated after myoclonic seizures developed at 4.5 years of age. Electroencephalograms showed semi-continuous bursts of diffuse irregular spike-wave complexes and MRI of the brain showed atrophy of the cerebellum and brainstem, and high signal intensities in the posterior periventricular triangle portion on T2-weighted images. Gene analysis performed at the age of 6 years revealed an expanded CAG repeat (17/74) at the DRPLA locus. The CAG repeat size was larger in this case than in cases of the adult and juvenile types with later onset, suggesting a correlation between repeat length and age at onset. Genetic examination of the family members was not performed because of her mother's fear and emotional confusion.

[Merosin-positive congenital muscular dystrophy with early orthopaedic problems in relation to Ullrich's disease].

We report three patients with sporadic merosin-positive congenital muscular dystrophy (CMD) with torticollis and/or developmental dislocation of the hip in early childhood. Diagnosis of merosin-positive CMD was based on their clinical and dystrophic muscle biopsy findings. At the age 13 months, patient 1 was found to have developmental dislocation of both hips, which was surgically treated at 5 years. Patient 2 had severe torticollis and contracture of both hip joints which had been present since the neonatal period, and underwent repair of the torticollis at 2 years. Patient 3 was found to have developmental dislocation of the left hip at one month of age. Although she had generalized muscle hypotonia she learned to walk at 23 months. She had no facial muscle involvement nor contracture of joints, but had hyperlaxity of distal joints. Her muscle biopsy showed complete collagen VI deficiency immunohistochemically. In contrast to merosin-deficient CMD, merosin-positive CMD appears to be a group of heterogeneous diseases. Since collagen VI was reported to be defective in Ullrich's disease, patient 3 may be diagnosed as having Ullrich's disease but had no typical clinical characteristics of the disease. Further study is needed to identify the pathogenetic mechanism of congenital muscular dystrophy with early joint abnormalities to determine whether there is a primary abnormality of the connective tissue including collagen VI.

CSF hypocretin-1 (orexin-A) concentrations in narcolepsy with and without cataplexy and idiopathic hypersomnia.

We measured cerebrospinal fluid (CSF) hypocretin-1 levels in 11 patients with narcolepsy-cataplexy, five with narcolepsy without cataplexy and 12 with idiopathic hypersomnia (IHS). All patients were Japanese. As reported in Caucasian patients, undetectable or very low hypocretin-1 levels were observed in most (9 out of 11) Japanese narcolepsy--cataplexy patients. Our hypocretin-deficient narcoleptics included three prepubertal cases within few months after the disease onset. All nine hypocretin-deficient patients were human leuckocyte antigen (HLA) DR2 positive, while two who had normal CSF hypocretin-1 levels were HLA DR2 negative. In contrast, none of the narcolepsy without cataplexy and IHS subjects had undetectable low levels. Low CSF hypocretin-1 is therefore very specific for HLA DR2 positive narcolepsy-cataplexy, and the deficiency is likely to be established at the early stage of the disease.