A novel homozygous change of CLCN2 (p.His590Pro) is associated with a subclinical form of leukoencephalopathy with ataxia (LKPAT)

2017
ClC-2 is a plasma membrane chloride channelwith widespread expression in the human body, including the brain. Its function is still being studied, although it is thought to have a role in ion and water homoeostasis in the brain. ClC-2 is part of a complex containing GlialCAM and MLC1. Both these genes are associated with autosomal recessive human leukodystrophieswith intramyelinic oedema. Biallelic mutations in CLCN2, encoding the ClC-2 channel, have been reported in patients with a rare form of leukoencephalopathywith ataxia (LKPAT; MIM #615651). No peculiar neurological features have been reported for this disease, although slight visual impairment due to chorioretinopathy or optic atrophy, mild ataxia, learning disabilities, and headaches are recurrent symptoms in patients. However, MRI shows a typical diagnostic pattern that consists of white matter signal abnormalities in the posterior limbs of the internal capsules, cerebral peduncles, pontine pyramidal tractsand in the middle cerebellar peduncles, associated with lower apparent diffusion coefficient values in most cases. Specific anomalies of brainstem auditory evoked potentials(BAEP) have also been described.1–3 Here, we report on a 52-year-old Moroccan woman presenting with mild and asymptomatic bilateral optic atrophy detected at a routine ophthalmological examination for presbyopia. Best-corrected high-contrast visual acuity was 20/20 in both eyes. Anterior segment and intraocular pressures were normal, and pupillary reflexeswere present. On fundus biomicroscopy, mild pallorand excavation of the optic …
    • Correction
    • Source
    • Cite
    • Save
    5
    References
    12
    Citations
    NaN
    KQI
    []
    Baidu
    map