Phenotypic variability related to dominant UCHL1 mutations: about three families with optic atrophy and ataxia.

INTRODUCTION: Ubiquitin C-terminal hydrolase L1 (UCHL1) has been associated with a severe, complex autosomal recessive spastic paraplegia (HSP79) [1] [2] [3] [4]. More recently, UCHL1 loss of function (LoF) variants have been associated to an autosomal dominant disease characterized by late-onset spastic ataxia, neuropathy, and frequent optic atrophy [5]. METHODS: Routine clinical care whole-genome (WGS) and exome (ES) sequencing. RESULTS: We present three families with autosomal dominant UCHL1-related disorder. The clinical phenotype mainly associated optic atrophy, mixed cerebellar and sensory ataxia, and possible hearing loss. We delineated two major phenotypes, even within the same family: (1) juvenile severe optic atrophy followed by a later-onset ataxia, or (2) late-onset ataxia with asymptomatic or mild optic atrophy. The families harboured three novel heterozygous variants in UCHL1: two loss of function (p.Lys115AsnfsTer40; c.171_174 + 7del11), and one missense (p.Asp176Asn) involving the catalytic site of the protein and potentially altering the adjacent splice site. DISCUSSION: We confirm the existence of dominantly inherited UCHL1 pathogenic variants. We describe a considerable intrafamilial phenotypic variability, with two main phenotypes. Optic atrophy was consistently present, but with varying degrees of severity. Neither delayed motor or intellectual development, nor dysmorphic features were part of the dominant phenotype in comparison with the autosomal recessive form. The molecular mechanism appears to be haploinsufficiency. UCHL1 monoallelic variants should therefore be considered in any case of early-onset optic atrophy or in late-onset complex ataxic syndrome with asymptomatic optic atrophy.

Adult-onset spinal muscular atrophy: An update.

Spinal muscular atrophy (SMA) refers to a group of disorders affecting lower motor neurons. The age of onset of these disorders is variable, ranging from the neonatal period to adulthood. Over the last few years, there has been enormous progress in the description of new genes and phenotypes that throw new light on the molecular pathways involved in motor neuron degeneration. Advances in our understanding of the pathophysiology of the most frequent forms, SMA linked to SMN1 gene mutations and Kennedy disease, has led to the development of therapeutic strategies currently being tested in clinical trials. This report provides a general overview of the clinical features and pathophysiological mechanisms in adult-onset genetic SMA disorders in which the causative gene has been identified (SMN1-related SMA, Kennedy disease, CHCHD10, TRPV4, DYNC1H1 and BICD2). Sporadic lower motor neuron disease, also known as progressive muscular atrophy (PMA), is also discussed. The finding of TDP-43 aggregates in immunohistochemical studies of PMA strongly supports the idea that it is a phenotypic variant of amyotrophic lateral sclerosis (ALS).

Bedside tested ocular motor disorders in multiple sclerosis patients.

Background/Aims. Ocular motor disorders (OMDs) are a common feature of multiple sclerosis (MS). In clinical practice, if not reported by patients, OMDs are often underdiagnosed and their prevalence is underestimated. Methods. We studied 163 patients (125 women, 76.7%, 38 men, 23.3%; median age 45.0 years; median disease duration 10 years; median EDSS 3.5) with definite MS (n = 150, 92%) or clinically isolated syndrome (n = 13, 8%) who underwent a thorough clinical examination of eye movements. Data on localization of previous relapses, MS subtype, and MRI findings were collected and analyzed. Results. Overall, 111/163 (68.1%) patients showed at least one abnormality of eye movement. Most frequent OMDs were impaired smooth pursuit (42.3%), saccadic dysmetria (41.7%), unilateral internuclear ophthalmoplegia (14.7%), slowing of saccades (14.7%), skew deviation (13.5%), and gaze evoked nystagmus (13.5%). Patients with OMDs had more severe disability (P = 0.0005) and showed more frequently infratentorial MRI lesions (P = 0.004). Localization of previous relapses was not associated with presence of OMDs. Conclusion. OMDs are frequent in patients with stable (no relapses) MS. A precise bedside examination of eye motility can disclose abnormalities that imply the presence of subclinical MS lesions and may have a substantial impact on definition of the diagnosis and on management of MS patients.

Spinal subarachnoid hematomas and cerebral infarctions in Goodpasture's disease.

INTRODUCTION: Goodpasture's disease with central nervous system involvement is extremely rare. CASE REPORT: We report a 62-year-old woman with Goodpasture's disease (GD) associated with the presence of perinuclear anti-neutrophil cytoplasmic antibodies, complicated by spinal subarachnoid hematomas and cerebral infarctions. In spite of aggressive treatment, the patient died. CONCLUSION: GD and anti-neutrophil cytoplasmic antibodies vasculitis should be suspected in patients presented with renal insufficiency with spinal and/or brain involvement.

[Brachial plexus sleep palsy]. / Paralysie du plexus brachial au réveil.

INTRODUCTION: Brachial plexus is rarely involved in "Saturday night palsy". CASE REPORT: A young man was admitted for numbness and weakness of his right upper limb after awaking from sleep. Neurophysiological studies, consistent with brachial plexopathy, revealed presence of proximal conduction blocks. Patient presented spontaneous clinical and neurophysiological improvement. DISCUSSION: Diagnosis of compressive brachial plexopathy needs to eliminate other causes of neuropathy with conduction block.

[Cryoglobulinemic peripheral neuropathy in hepatitis C virus infection: clinical and anatomical correlations of 22 cases]. / Corrélations anatomocliniques des neuropathies périphériques cryoglobulinémiques secondaires à l'hépatite C. Série consécutive de 22 cas.

INTRODUCTION: Cryoglobulinemic neuropathies caused by hepatitis C virus are frequent and may have severe clinical outcomes. The aim of this study was to clarify the clinical and anatomical correlations of these neuropathies. METHODS: Between 1992 and 2007, 22 consecutive patients with cryoglobulinemic neuropathies caused by hepatitis C virus were retrospectively included. Patients were evaluated clinically, electrophysiologically and underwent a neuromuscular biopsy. The group of patients with vasculitis on nerve biopsy was compared with the group without vasculitis. RESULTS: All the neuropathies were axonal with 11 polyneuropathies and 11 mononeuropathies multiplex. The seven patients with medium-sized vasculitis on the nerve biopsy presented an acute sensorimotor mononeuropathy multiplex in six cases (85%), with ischemic conduction block in three cases (42%) and wallerian degeneration in four cases (57%). Among the four patients with small-sized vasculitis, two had a mononeuropathy multiplex (50%) without conduction block (0%) and with wallerian degeneration in one case (25%). The 11 patients without vasculitis (nine lymphocytic perivascular infiltrates and two non inflammatory biopsies) had a polyneuropathy in eight cases (72%) without conduction block and wallerian degeneration (0%). The type of neuropathy was different in the group of patients with vasculitis compared with the group without vasculitis. The neuropathies with vasculitis were significantly different with more frequent mononeuropathies multiplex (p<0.05), acute early stage (p<0.01), disability (p<0.05) and wallerian degeneration (p=0.01). CONCLUSION: Among hepatitis C patients with cryoglobulinemia, neuropathies with small-sized vasculitis show a pattern between severe mononeuropathies multiplex with medium-sized vasculitis and moderate polyneuropathies with lymphocytic perivascular infiltrates. In cryoglobulinemic vasculitis with hepatitis C, the severity of the neuropathy depends on the nature of the cellular inflammation and the size of the vessel involvement.

GQ1b ganglioside antibody-related disorders: a case with a complex phenotype.

We described an overlap syndrome associating Miller Fisher syndrome (MFS) and acute inflammatory demyelinating polyradiculoneuropathy (AIDP). Furthermore, the patient presented unusual neurological manifestations including headache, T10 sensory level, urinary urgency, and gadolinium enhancement of the spinal roots. One year follow-up was characterized by clinical recovery and persistent high rates of anti-GQ1b, -GD1b and -GT1b antibodies. Our case suggests broad phenotype of persistent antigangliosides antibodies.