Neuroimaging in diagnosis of atypical polyradiculoneuropathies: report of three cases and review of the literature

Neuroimaging is increasingly used in the study of peripheral nerve diseases, and sometimes may have a pivotal role in the diagnostic process. We report on three patients with atypical chronic inflammatory polyradiculoneuropathy (CIDP) in whom magnetic resonance imaging (MRI) and nerve Ultrasound (US) were crucial for a correct diagnostic work-out. A literature review on MRI and US in acquired demyelinating polyneuropathies is also provided. Awareness of the imaging features of CIDP will assist in confirmation of the diagnosis, institution of the appropriate therapy, and prevention of inadequate or delayed treatment in atypical CIDP.

Charcot-Marie-Tooth 2F: phenotypic presentation of the Arg136Leu HSP27 mutation in a multigenerational family

Mutations in the small heat-shock protein HSP27 gene are associated with distal hereditary motor neuropathy and with the axonal form of Charcot-Marie-Tooth disease type 2. We present the clinical and electrophysiological data on a multigenerational family with the p.Arg136Leu HSP27 mutation. Atypical features such as deafness and pyramidal signs were present in our cases adding new data to the large spectrum of HSP27-related phenotype.

Is overwork weakness relevant in Charcot-Marie-Tooth disease?

BACKGROUND

In overwork weakness (OW), muscles are increasingly weakened by exercise, work or daily activities. Although it is a well-established phenomenon in several neuromuscular disorders, it is debated whether it occurs in Charcot-Marie-Tooth disease (CMT). Dominant limb muscles undergo a heavier overload than non-dominant and therefore if OW occurs we would expect them to become weaker. Four previous studies, comparing dominant and non-dominant hand strength in CMT series employing manual testing or myometry, gave contradictory results. Moreover, none of them examined the behaviour of lower limb muscles.

METHODS

We tested the OW hypothesis in 271 CMT1A adult patients by comparing bilateral intrinsic hand and leg muscle strength with manual testing as well as manual dexterity.

RESULTS

We found no significant difference between sides for the strength of first dorsal interosseous, abductor pollicis brevis, anterior tibialis and triceps surae. Dominant side muscles did not become weaker than non-dominant with increasing age and disease severity (assessed with the CMT Neuropathy Score); in fact, the dominant triceps surae was slightly stronger than the non-dominant with increasing age and disease severity.

DISCUSSION

Our data does not support the OW hypothesis and the consequent harmful effect of exercise in patients with CMT1A. Physical activity should be encouraged, and rehabilitation remains the most effective treatment for CMT patients.

Neuropathy in eosinophilic granulomatosis with polyangiitis: a comparison study of 24 cases with or without prior leukotriene antagonist exposure

Eosinophilic granulomatosis with polyangiitis (EGPA), also known as Churg-Strauss syndrome (CSS), is a systemic vasculitis affecting almost exclusively patients with asthma. Neuropathy is the presenting feature in 55-75 % of cases. An increased incidence of the syndrome has been reported in asthmatics treated with leukotriene antagonists (LTAs). The causal relation is still debated. We retrospectively examined clinical, biochemical, histological features, and outcome of patients referred between 1990 and 2006 for sural nerve biopsy affected by neuropathy related to EGPA. We identified 24 patients, 6 treated with LTA montelukast (T-group) and 18 not treated (NT-Group). All had chronic asthma; in T-group neuropathy developed from 1 to 150 days after starting montelukast. Demographic features as well as asthma duration and pre-onset treatment were remarkably similar, with the only exception of a statistically nonsignificant larger involvement of the nasal mucosa in T group. Nerve biopsy revealed in both group an axonal neuropathy. At follow-up, all within the T-group and most within the NT-group improved clinically; neurophysiological parameters remained stable, improved or worsened in the same proportion within the two groups. Only 2 NT and no T-patient had stopped steroid treatment before the appearance of the peripheral neuropathy, making withdrawal overall unlikely as a causative factor of the onset of neuropathy. In summary, the temporal relationship between montelukast administration and the onset of neuropathy, would make the latter more likely as an "adverse drug reaction". Despite this, no significant clinical neither neurophysiological differences were noted between the two groups.

Executive dysfunctions in migraine with and without aura: what is the role of white matter lesions?

OBJECTIVE/BACKGROUND

Executive dysfunctions and white matter lesions on magnetic resonance imaging have been reported in migraine. The aim of this study was to determine whether any correlation between these 2 variables exists.

MATERIALS AND METHODS

Forty-four subjects affected by migraine with or without aura were compared with 16 healthy subjects. A battery of neuropsychological tests assessing executive functions was administered to all subjects. Number and total volume of white matter lesions were assessed in the whole brain and in the frontal lobe.

RESULTS

The performances of both groups of migraineurs, with and without aura, were significantly worse when compared with controls on Boston Scanning Test. Moreover, we found lower performances compared with controls respectively on Frontal Assessment Battery in patients with migraine with aura and on Controlled Oral Word Association Test in patients with migraine without aura. Nineteen patients (43.2%) and one control subject (6.2%) had white matter lesions. We did not find any significant correlation between white matter lesions load and neuropsychological performances.

CONCLUSIONS

On the basis of our results, white matter lesions load on magnetic resonance imaging do not seem to contribute to neuropsychological performances deficit in migraineurs.

Traumatic labyrinthine concussion in a patient with sensorineural hearing loss

Blunt head trauma without any temporal bone fracture or longitudinal temporal bone fracture, with an associated fracture of the labyrinth may cause labyrinthine injury with sensor neural hearing loss and vertigo because of a concussive injury to the membranous labyrinth. Sudden sensory neural hearing loss is relatively frequent. In most cases, the etiology is not discovered. One of the possible causes for sudden deafness is inner labyrinth bleeding or concussion, which were difficult to diagnose before the advent of magnetic resonance imaging. Vertigo without a demonstrable fracture may also be the result of labyrinthine concussion, cupololithiasis and perilymphatic fistula. We describe the clinical case of a patient with acute traumatic hearing loss and vertigo, without skull base fracture detected on computed tomography. Magnetic resonance study was also performed. We have integrated the discussion with features that allow the differential diagnosis from other similar conditions.

Vascular cerebral anomalies associated with Septo-Optic Dysplasia. A case report

We describe a case of Septo-Optic Dysplasia (SOD) characterized by the presence of anomalous cerebral vessels. In our young patient the classical features of SOD were associated with vascular anomalies including absence of the vein of Galen, right Rosenthal vein leading to the superior petrosal sinus, and anomalous origin of the anterior choroidal arteries. These findings have never been associated with SOD in the literature but their revelation supports the hypothesis of a vascular disruption as a possible cause of the SOD.

A pan-European study of the C9orf72 repeat associated with FTLD: geographic prevalence, genomic instability, and intermediate repeats

We assessed the geographical distribution of C9orf72 G(4) C(2) expansions in a pan-European frontotemporal lobar degeneration (FTLD) cohort (n = 1,205), ascertained by the European Early-Onset Dementia (EOD) consortium. Next, we performed a meta-analysis of our data and that of other European studies, together 2,668 patients from 15 Western European countries. The frequency of the C9orf72 expansions in Western Europe was 9.98% in overall FTLD, with 18.52% in familial, and 6.26% in sporadic FTLD patients. Outliers were Finland and Sweden with overall frequencies of respectively 29.33% and 20.73%, but also Spain with 25.49%. In contrast, prevalence in Germany was limited to 4.82%. In addition, we studied the role of intermediate repeats (7-24 repeat units), which are strongly correlated with the risk haplotype, on disease and C9orf72 expression. In vitro reporter gene expression studies demonstrated significantly decreased transcriptional activity of C9orf72 with increasing number of normal repeat units, indicating that intermediate repeats might act as predisposing alleles and in favor of the loss-of-function disease mechanism. Further, we observed a significantly increased frequency of short indels in the GC-rich low complexity sequence adjacent to the G(4) C(2) repeat in C9orf72 expansion carriers (P < 0.001) with the most common indel creating one long contiguous imperfect G(4) C(2) repeat, which is likely more prone to replication slippage and pathological expansion.

Guillain-Barré Syndrome Associated with Acute Onset Bilateral Facial Nerve Palsies

Guillain-Barré syndrome is a post infectious, immune-mediated disease with cranial nerve involvement observed in 45–75% of patients. Bilateral facial nerve palsy is rather uncommon and occurs in 0.3% to 2% of all facial palsies. We describe a rare case of a 29-year-old man with bilateral facial palsy caused by a Guillain-Barré syndrome with an unusual onset and progression of neurological symptoms. Neuroradiological findings in our patient are described and compared with data from literature on bilateral facial palsies to make differential diagnosis easier for neuroradiologists.

An occult spinal neurenteric cyst associated with congenital hemivertebrae. A case report

We describe a case of an occult spinal neurenteric cyst associated with congenital hemivertebrae. Different intraspinal anomalies, such as neurenteric cysts (representing 0.3 to 0.5 % of all spinal tumors) have been reported in association with congenital hemivertebrae. Indeed, although CT is the best examination to study vertebral anomalies, MRI should be performed in order to exclude a more complex dysraphic condition.

Ascorbic acid in Charcot-Marie-Tooth disease type 1A (CMT-TRIAAL and CMT-TRAUK): a double-blind randomised trial

BACKGROUND

Ascorbic acid reduced the severity of neuropathy in transgenic mice overexpressing peripheral myelin protein 22 (PMP22), a model of Charcot-Marie-Tooth disease type 1A (CMT1A) associated with the PMP22 duplication. However, in three 1-year trials, ascorbic acid had no benefit in human beings. We did a multicentre 2-year trial to test the efficacy and tolerability of ascorbic acid in patients with CMT1A.

METHODS

Adult patients (aged 18-70 years) with symptomatic CMT1A were enrolled from nine centres in Italy and the UK, and were randomly assigned (1:1 ratio) to receive 1·5 g/day oral ascorbic acid or matching placebo for 24 months. The randomisation sequence was computer generated by block randomisation, stratified by centre and disease severity, and patients were allocated to treatment by telephone. The primary outcome was change in the CMT neuropathy score (CMTNS) at 24 months. Secondary outcomes were timed 10 m walk test, nine-hole peg test, overall neuropathy limitations scale, distal maximal voluntary isometric contraction, visual analogue scales for pain and fatigue, 36-item short-form questionnaire, and electrophysiological measurements. Patients, treating physicians, and physicians assessing outcome measures were masked to treatment allocation. Analysis of the primary outcome was done on all randomised patients who received at least one dose of study drug. This study is registered, numbers ISRCTN61074476 (CMT-TRAUK) and EudraCT 2006-000032-27 (CMT-TRIAAL).

FINDINGS

We enrolled and randomly assigned 277 patients, of whom six (four assigned to receive ascorbic acid) withdrew consent before receiving treatment; 138 receiving ascorbic acid and 133 receiving placebo were eligible for analysis. Treatment was well tolerated: 241 of 271 patients (89% in each group) completed the study; 20 patients (nine receiving ascorbic acid) dropped out because of adverse events. Mean CMTNS at baseline with missing data imputed was 14·7 (SD 4·8) in the ascorbic acid group and 13·9 (4·2) in the placebo group. Mean worsening of CMTNS was 0·2 (SD 2·8, 95% CI -0·3 to 0·7) in the ascorbic acid group and 0·2 (2·7, -0·2 to 0·7) in the placebo group (mean difference 0·0, 95% CI -0·6 to 0·7; p=0·93). We recorded no differences between the groups for the secondary outcomes at 24 months. 21 serious adverse events occurred in 20 patients, eight in the ascorbic acid group and 13 in the placebo group.

INTERPRETATION

Ascorbic acid supplementation had no significant effect on neuropathy compared with placebo after 2 years, suggesting that no evidence is available to support treatment with ascorbic acid in adults with CMT1A.

FUNDING

Telethon-UILDM and AIFA (Italian Medicines Agency) for CMT-TRIAAL, and Muscular Dystrophy Campaign for CMT-TRAUK.

Four novel cases of periaxin-related neuropathy and review of the literature

OBJECTIVE

To report 4 cases of autosomal recessive hereditary neuropathy associated with novel mutations in the periaxin gene (PRX) with a review of the literature. Periaxin protein is required for the maintenance of peripheral nerve myelin. Patients with PRX mutations have early-onset autosomal recessive demyelinating Charcot-Marie-Tooth disease (CMT4F) or Déjèrine-Sottas neuropathy (DSN). Only 12 different mutations have been described thus far.

METHODS

Case reports and literature review.

RESULTS

Four patients from 3 unrelated families (2 siblings and 2 unrelated patients) were affected by an early-onset, slowly progressive demyelinating neuropathy with relevant sensory involvement. All carried novel frameshift or nonsense mutations in the PRX gene. The 2 siblings were compound heterozygotes for 2 PRX null mutations (p.Q547X and p.K808SfsX2), the third patient harbored a homozygous nonsense mutation (p.E682X), and the last patient had a homozygous 2-nt insertion predicting a premature protein truncation (p.S259PfsX55). Electrophysiologic analysis showed a severe slowing of motor nerve conduction velocities (MNCVs, between 3 and 15.3 m/s) with undetectable sensory nerve action potentials (SNAPs). Sural nerve biopsy, performed in 2 patients, demonstrated a severe demyelinating neuropathy and onion bulb formations. Interestingly, we observed some variability of disease severity within the same family.

CONCLUSIONS

These cases and review of the literature indicate that PRX-related neuropathies have early onset but overall slow progression. Typical features are prominent sensory involvement, often with sensory ataxia; a moderate-to-dramatic reduction of MNCVs and almost invariable absence of SNAPs; and pathologic demyelination with classic onion bulbs, and less commonly myelin folding and basal lamina onion bulbs.

Atypical Alzheimer's disease: a case report

This paper deals with an unusual case of Alzheimer's disease with early onset, no family history, myoclonus, tonic generalized seizures and pseudo-periodic spikes on EEG. The demise occurred after 8 years of progressive cognitive deterioration; the pathological examination showed "Pick-like" atrophy, neurofibrillary tangles, senile plaques, congophilic angiopathy and cerebellar amyloid plaques. The genetical research could not support the hypothesis of a mutation of Presenilin 1 and 2 genes. Anyway, the peculiarity of the phenotype is worthy to be described even in the absence of specific molecular findings.