Report of a novel ATP7A mutation causing distal motor neuropathy.

We describe a novel ATP7A gene mutation associated with distal motor neuropathy, mild connective tissue abnormalities and autonomic disturbances. Next-generation sequencing analysis of a lower-motor neuron diseases gene panel was performed in two sibs presenting with distal motor neuropathy plus an autonomic dysfunction, which main manifestations were retrograde ejaculation, diarrhea and hyperhydrosis. Probands underwent dysmorphological, neurological, electrophysiological as well as biochemical evaluations and somatic and autonomic innervation studies on skin biopsies. A novel missense mutation (p.A991D) was identified in the X-linked ATP7A gene, segregating in both brothers and inherited from their healthy mother. Biochemical studies on patients' blood samples showed reduced serum copper and ceruloplasmin levels. Clinical and neurophysiological evaluation documented dysautonomic signs. Quantitative evaluation of skin innervation disclosed a small fiber neuropathy with prevalent autonomic involvement. Mutations in the ATP7A gene, encoding for a copper-transporting ATPase, have been associated with the severe infantile neurodegenerative Menkes disease and in its milder variant, the Occipital Horn Syndrome. Only two ATP7A mutations were previously reported as causing, a pure axonal distal motor neuropathy (dHMN-SMAX3). The phenotype we report represents a further example of this rare genotype-phenotype correlation and highlights the possible occurrence in SMAX3 of autonomic disturbances, as described for Menkes disease and Occipital Horn Syndrome.

SERCA1 protein expression in muscle of patients with Brody disease and Brody syndrome and in cultured human muscle fibers.

Brody disease is an inherited myopathy associated with a defective function of sarcoplasmic/endoplasmic reticulum Ca(2+)-ATPase 1 (SERCA1) protein. Mutations in the ATP2A1 gene have been reported only in some patients. Therefore it has been proposed to distinguish patients with ATP2A1 mutations, Brody disease (BD), from patients without mutations, Brody syndrome (BS). We performed a detailed study of SERCA1 protein expression in muscle of patients with BD and BS, and evaluated the alternative splicing of SERCA1 in primary cultures of normal human muscle and in infant muscle. SERCA1 reactivity was observed in type 2 muscle fibers of patients with and without ATP2A1 mutations and staining intensity was similar in patients and controls. Immunoblot analysis showed a significant reduction of SERCA1 band in muscle of BD patients. In addition we demonstrated that the wild type and mutated protein exhibits similar solubility properties and that RIPA buffer improves the recovery of the wild type and mutated SERCA1 protein. We found that SERCA1b, the SERCA1 neonatal form, is the main protein isoform expressed in cultured human muscle fibers and infant muscle. Finally, we identified two novel heterozygous mutations within exon 3 of the ATP2A1 gene from a previously described patient with BD.

Conversion ratio between Dysport and Botox in clinical practice: an overview of available evidence.

The optimal conversion ratio between Dysport and Botox--the two botulinum neurotoxin type A products (BoNT-As) supported by the larger bulk of evidence-has been extensively debated, because of its broad medical and economic implications. The article discusses the available evidence on the conversion ratio between Dysport and Botox in adults affected by spasticity, cervical dystonia, blepharospasm and hemifacial spasm, with a focus on clinical trials that specifically addressed this issue. In addition, some suggestions on the conversion ratio between Dysport and Xeomin can be extrapolated, since Xeomin has the same efficacy and safety profile as Botox and is exchangeable with Botox with a 1:1 conversion ratio. Taken together, the findings retrieved from this literature research suggest that a conversion ratio of 3:1 (Dysport:Botox)--or even lower--can be considered appropriate for the treatment of the above-mentioned conditions. Higher conversion ratios may lead to an overdosing of Dysport, with a potential increased incidence of adverse events. Therefore, we recommend that physicians using both products consider using a lower conversion factor as a guide, adjusting it upwards as required based on the specific characteristics and response to treatment of each patient.

Botulinum toxin treatment for slipping rib syndrome: a case report.

BACKGROUND: Slipping rib syndrome (SRS) is a musculoskeletal cause of severe and recurrent thoracic or abdominal pain. The etiology of SRS is unknown, it seems to arise from costal hypermobility with a tendency of one of the ribs (usually from 8th to 10th but also 11th and 12th have been described) to slip under the superior adjacent rib. Its prevalence is underestimated because SRS is mainly a clinical diagnosis, frequently missed. The critical aspect of the diagnosis is knowledge of the condition itself, which, when lacking, often results in the patient being referred to many different specialists and exposed to unnecessary and costly investigations. The management of the condition includes conservative techniques such as manipulation, localized anesthetic, and steroid or anesthetic nerve block. However, where conservative therapy fails, surgical treatment, with excision of the rib, may be performed. METHODS: In this paper we describe the case of a patient with persistent and debilitating flank pain who, after many investigations, was diagnosed with SRS. RESULTS: The usual conservative treatment failed, after which we treated the patient with injections of incobotulinumtoxin A into muscles inserting on the inferior side of the rib cage (quadratus lumborum muscle, muscle transversus abdomini, abdominal external oblique muscle, and recto abdomini) achieving a complete relief from pain. CONCLUSIONS: To our knowledge botulinum toxin has never been proposed before for the treatment of SRS. We believe that it should be considered as a therapeutic option, especially where other medical treatments have failed or as an intermediate step before surgical intervention.

Genetic characterization in symptomatic female DMD carriers: lack of relationship between X-inactivation, transcriptional DMD allele balancing and phenotype.

BACKGROUND: Although Duchenne and Becker muscular dystrophies, X-linked recessive myopathies, predominantly affect males, a clinically significant proportion of females manifesting symptoms have also been reported. They represent an heterogeneous group characterized by variable degrees of muscle weakness and/or cardiac involvement. Though preferential inactivation of the normal X chromosome has long been considered the principal mechanism behind disease manifestation in these females, supporting evidence is controversial. METHODS: Eighteen females showing a mosaic pattern of dystrophin expression on muscle biopsy were recruited and classified as symptomatic (7) or asymptomatic (11), based on the presence or absence of muscle weakness. The causative DMD gene mutations were identified in all cases, and the X-inactivation pattern was assessed in muscle DNA. Transcriptional analysis in muscles was performed in all females, and relative quantification of wild-type and mutated transcripts was also performed in 9 carriers. Dystrophin protein was quantified by immunoblotting in 2 females. RESULTS: The study highlighted a lack of relationship between dystrophic phenotype and X-inactivation pattern in females; skewed X-inactivation was found in 2 out of 6 symptomatic carriers and in 5 out of 11 asymptomatic carriers. All females were characterized by biallelic transcription, but no association was found between X-inactivation pattern and allele transcriptional balancing. Either a prevalence of wild-type transcript or equal proportions of wild-type and mutated RNAs was observed in both symptomatic and asymptomatic females. Moreover, very similar levels of total and wild-type transcripts were identified in the two groups of carriers. CONCLUSIONS: This is the first study deeply exploring the DMD transcriptional behaviour in a cohort of female carriers. Notably, no relationship between X-inactivation pattern and transcriptional behaviour of DMD gene was observed, suggesting that the two mechanisms are regulated independently. Moreover, neither the total DMD transcript level, nor the relative proportion of the wild-type transcript do correlate with the symptomatic phenotype.

Effect of short-term electrical stimulation before and after botulinum toxin injection.

OBJECTIVE: To compare the effect of electrical stimulation applied before and after botulinum toxin injection. SUBJECTS: Eight healthy subjects. METHODS: Both extensor digitorum brevis muscles were injected with low fixed doses of botulinum toxin. Subjects received a 20-min session of electrical stimulation before botulinum toxin injection for the right foot and after the injection for the left foot. Percentage changes in compound muscle action potential amplitude were calculated at different intervals over a 60-day period. RESULTS: A reduction in compound muscle action potential percentage was measured at every time-point, both for the muscles stimulated before injection of botulinum toxin and for those stimulated after injection. The compound muscle action potential percentage was always lower on the side stimulated after injection of botulinum toxin. A reduction in compound muscle action potential percentage was measured on the 7th and 15th days in all extensor digitorum brevis muscles examined. On the 15th day the compound muscle action potential percentage was 38.8 (right foot) vs 24.1 (left foot) (p=0.0117). A slow recovery was observed after this period. CONCLUSION: Electrical nerve stimulation enhances the effect of botulinum toxin to a greater extent if applied after injection rather than before. The short stimulation time used in our study gave similar results to those seen in previous research using longer application times.

Multiphasic acute disseminated encephalomyelitis or pediatric multiple sclerosis: report of an atypical case.

An international panel has recently proposed consensus definitions for pediatric multiple sclerosis and related disorders. These are important diagnostic improvements, but exceptions have been acknowledged. Further insight about clinical overlap between pediatric multiple sclerosis and all forms of relapsing acute disseminated encephalomyelitis may be gained from long-term follow-up. We report an 8-year follow-up of a girl who developed multiple episodes of central nervous system demyelination at the age of 3 years consistent with multiphasic acute disseminated encephalomyelitis. At 10 years of age (7 years after the first clinical event), she developed progressive cognitive deterioration, mood disorder, and headache, suggesting a secondary progressive form of multiple sclerosis. Magnetic resonance imaging and cerebrospinal fluid analysis were equivocal while visual evoked potentials were the sole test in favor of a diagnosis of multiple sclerosis. A multifaceted approach may be needed when dealing with atypical cases of demyelinating disease in young children.

Brain white matter damage in SCA1 and SCA2. An in vivo study using voxel-based morphometry, histogram analysis of mean diffusivity and tract-based spatial statistics.

BACKGROUND AND PURPOSE: Neurodegeneration in spinocerebellar ataxia type 1(SCA1) and 2(SCA2) is associated with white matter(WM) damage. Voxel-Based Morphometry(VBM), histogram analysis of mean diffusivity(MD) and Tract-Based Spatial Statistics(TBSS) enable an in vivo quantitative analysis of WM volume and structure. We assessed with these 3 techniques the whole brain WM damage in SCA1 and SCA2. PATIENTS AND METHODS: Ten patients with SCA1, 10 patients with SCA2 and 10 controls underwent MRI with acquisition of T1-weighted and diffusion tensor images. The results were correlated with severity of clinical deficit. RESULTS: VBM showed atrophy of the brainstem and cerebellar WM without significant differences between SCA1 and SCA2. Focal atrophy of the cerebral subcortical WM was also present. Histogram analysis revealed increased MD in the brainstem and cerebellum in patients with SCA1 and SCA2 which in SCA2 was more pronounced and combined with mild increase of the MD in the cerebral hemispheres in SCA2. In SCA1 and SCA2 TBSS revealed decreased fractional anisotropy(FA) in the inferior, middle and superior cerebellar peduncles, pontine transverse fibres, medial and lateral lemnisci, spinothalamic tracts, corticospinal tracts and corpus callosum. The extent of tract changes was greater in SCA2 patients who also showed decreased FA in the short intracerebellar tracts. In both diseases VBM, histogram and TBSS results correlated with clinical severity. CONCLUSIONS: Brain WM damage featuring a pontocerebeellar atrophy is similar in SCA1 and SCA2 but more pronounced in SCA2. In both diseases it correlates with severity of the clinical deficit.

Acute disseminated encephalomyelitis in children: focus on relapsing patients.

This study investigated the possible prognostic factors for relapse, and the diagnostic criteria for multiple sclerosis and related disorders, in pediatric acute disseminated encephalomyelitis. The study population comprised 24 Italian children with a mean age at onset of 6.9 years, and a mean follow-up time of 52.8 months (range, 12-180). Clinical, neurophysiologic, spinal-fluid, neuroradiologic, and outcome features were investigated. All patients but 2, who were reclassified as exhibiting clinically isolated syndromes, fulfilled the new classification criteria for acute disseminated encephalomyelitis recently proposed by the International Pediatric Multiple Sclerosis Study Group. Three patients relapsed after 3 months, 2 years, and 8 years, respectively. By the second attack, the diagnosis of multiple sclerosis, as well as of multiphasic disseminated encephalomyelitis, could be rendered using the revised criteria of McDonald et al. Long-term follow-up seemed to confirm a chronic disease course in 2 children. We could not identify features at onset to predict outcomes of patients. However, early in follow-up, the appearance of oligoclonal immunoglobulin G bands in spinal fluid and the persistence of visual-evoked potential abnormalities were associated with poor outcomes.

Brain structural damage in spinocerebellar ataxia type 1 : a VBM study.

BACKGROUND AND OBJECTIVE: Neuropathological description of the brain in spinocerebellar ataxia type 1(SCA1) is limited to a few cases. Voxel-based morphometry (VBM) enables an unbiased in vivo whole-brain quantitative analysis of regional differences in gray matter (GM) and white matter (WM) volume. We assessed with VBM the structural damage in patients with genetically confirmed SCA1. METHOD: Fifteen SCA1 patients and 15 age-matched healthy controls underwent MR examination with acquisition of high-resolution T1-weighted images. The results were correlated with the disease duration and severity of the clinical deficit assessed with the International Cerebellar Ataxia Rating Scale (ICARS) and Inherited Ataxia Clinical Rating Scale (IACRS). RESULTS: As compared to controls, patients with SCA1 showed a significant (p < 0.05 corrected for multiple comparison) symmetric loss of volume of the GM in the rostral cerebellar vermis and paramedian portions of the anterior cerebellar lobes. WM was decreased in the peridentate region and middle cerebellar peduncles but not in the pons. No GM or WM volume loss was found in the cerebral hemispheres. The cerebellar and brainstem GM and WM volume loss correlated with disease duration and the ICARS and IACRS scores. CONCLUSIONS: VBM confirms that atrophy predominantly involves the brainstem and cerebellum in SCA1. The correlation with the clinical features indicates that VBM might be useful to monitor disease progression.

Reliability of a novel neurostimulation method to study involuntary muscle phenomena.

Experimental methods involving painful electrical stimulation of a peripheral nerve showed the existence of a minimum stimulation frequency capable of inducing cramp, termed "threshold frequency" (TF). Our aim was to test an alternative method to induce fasciculations and cramps electrically. Two daily sessions of electrical stimulation of the abductor hallucis muscle were performed in 19 volunteers on 3 days: stimulation trains of 150 monophasic square pulses (duration 152 micros) of increasing frequency (current intensity 30% higher than maximal; frequency of the first trial, 4 pps; recovery between trials, 1 min) were delivered to the main muscle motor point until a cramp developed. Once a cramp was induced the protocol was repeated after 30 min. To verify by electromyography that cramp occurred, a surface electrode array was placed between the motor point and the distal tendon. Ambient and skin temperature were kept constant in all sessions. Fasciculations and cramps were elicited in all subjects. We observed the following median (interquartile range) values of TF: day 1 (session 1), 13 (6) pps; day 1 (session 2), 16 (4) pps; day 2 (session 1), 16 (6) pps; day 2 (session 2), 18 (6) pps; day 3 (session 1), 17 (4) pps; day 3 (session 2), 18 (8) pps. TF intersession intraclass correlation coefficients were 0.82, 0.92, and 0.90 for days 1, 2, and 3, respectively. TF interday intraclass correlation coefficient was 0.85. The absence of pain due to the stimulation and the demonstration of TF reliability support the use of our method for the study of involuntary muscle phenomena.

Acetyl-L-carnitine for the treatment of chemotherapy-induced peripheral neuropathy: a short review.

Peripheral neurotoxicity is a major complication associated with the use of chemotherapeutic agents such as platinum compounds, taxanes and vinca alkaloids. The neurotoxicity of chemotherapy depends not only on the anticancer agent(s) used, the cumulative dose and the delivery method, but also on the capacity of the nerve to cope with the nerve-damaging process. The sensory and motor symptoms and signs of neurotoxicity are disabling, and have a significant impact on the quality of life of cancer patients. Moreover, the risk of cumulative toxicity may limit the use of highly effective chemotherapeutic agents. Therefore, prophylaxis and treatment of peripheral neurotoxicity secondary to chemotherapy are major clinical issues. Acetyl-L-carnitine (ALC), the acetyl ester of L-carnitine, plays an essential role in intermediary metabolism. Some of the properties exhibited by ALC include neuroprotective and neurotrophic actions, antioxidant activity, positive actions on mitochondrial metabolism, and stabilisation of intracellular membranes. ALC has demonstrated efficacy and high tolerability in the treatment of neuropathies of various aetiologies, including chemotherapy-induced peripheral neuropathy (CIPN). In several experimental settings, the prophylactic administration of ALC prevented the occurrence of peripheral neurotoxicity commonly induced by chemotherapeutic agents. In animal models of CIPN, ALC administration promoted the recovery of nerve conduction velocity, restored the mechanical nociceptive threshold, and induced analgesia by up-regulating the expression of type-2 metabotropic glutamate receptors in dorsal root ganglia. These results, plus the favourable safety profile of ALC in neuropathies of other aetiologies, have led to the effects of ALC on CIPN being investigated in cancer patients. Preliminary results have confirmed the reasonably good tolerability profile and the efficacy of ALC on CIPN. The present studies support the use of ALC in cancer patients with persisting neurotoxicity induced by paclitaxel or cisplatin treatment.

Recovery of swallowing disorders in patients undergoing supracricoid laryngectomy with botulinum toxin therapy.

In recent decades, functional laryngeal surgery has become a widespread method of treating glottic and supraglottic neoplasms, since it ensures an oncological outcome comparable to that of radical surgery and functional results that are conducive to a good quality of life. The most common postoperative complaints for this type of surgery are swallowing disorders, which can thwart good surgical results, especially when severe. Five supracricoid laryngectomees with swallowing disorders unresolved by speech therapy were treated by percutaneous injection of botulinum toxin under electromyographic control. All patients presented marked improvement in their complaints. A single session of botulinum toxin type A treatment resolved the dysphagia in all cases.

Acetyl-L-carnitine (levacecarnine) in the treatment of diabetic neuropathy. A long-term, randomised, double-blind, placebo-controlled study.

OBJECTIVE: To assess the efficacy and tolerability of acetyl-L-carnitine (levacecarnine; LAC) versus placebo in the treatment of diabetic neuropathy, mainly by evaluating the effects of treatment on electrophysiological parameters and pain symptoms. DESIGN: This was a multicentre (n = 20), randomised, double-blind, placebo-controlled, parallel-group study. PATIENTS: 333 patients meeting clinical and/or neurophysiological criteria for diabetic neuropathy were enrolled. INTERVENTIONS: Patients were randomised to treatment with LAC or placebo. LAC (or placebo) was started intramuscularly at a dosage of 1000 mg/day for 10 days and continued orally at a dosage of 2000 mg/day for the remainder of the study (355 days). MAIN OUTCOME PARAMETERS AND RESULTS: The main efficacy parameter was the effect of treatment on 6- and 12-month changes from baseline in nerve conduction velocity (NCV) and amplitude in the sensory (ulnar, sural and median) and motor (median, ulnar and peroneal) nerves. The effect of treatment on pain was also evaluated by means of a visual analogue scale (VAS). Among the 294 patients with impaired electrophysiological parameters at baseline, those treated with LAC showed a statistically significant improvement in mean NCV and amplitude compared with placebo (p < 0.01). The greatest changes in NCV (at 12 months) were observed in the sensory sural nerve (7 m/sec in the LAC group vs +1.0 m/sec in the placebo group), sensory ulnar nerve (+2.9 vs +0.1 m/sec, respectively) and motor peroneal nerve (+2.7 vs -0.2 m/sec), whereas the greatest changes in amplitude were recorded in the motor peroneal nerve (+2.2 vs +0.1 mV). After 12 months of treatment, mean VAS scores for pain were significantly reduced from baseline by 39% in LAC-treated patients (p < 0.0 vs baseline) compared with 8% in placebo recipients. LAC was well tolerated over the study period. CONCLUSIONS: LAC was effective and well tolerated in improving neurophysiological parameters and in reducing pain over a 1-year period. LAC is, therefore, a promising treatment option in patients with diabetic neuropathy.

Botulinum neurotoxin serotypes A and C do not affect motor units survival in humans: an electrophysiological study by motor units counting.

OBJECTIVES: Botulinum neurotoxin serotype A (BoNT/A) is a valid therapy for dystonia but repeated BoNT/A injections may induce a clinical immuno-resistance that could be overcome by using other BoNT serotypes. In vitro experiments and our preliminary investigations in vivo, indicate that botulinum neurotoxin serotype C (BoNT/C) could be an effective alternative to BoNT/A. Moreover, in cultured neurons 'in vitro' BoNT/C has been reported to be more toxic than BoNT/A. METHODS: To verify this possibility, we compare the effect of BoNT/C and BoNT/A on the motor units count in humans by using the electrophysiological motor unit number estimation (MUNE) technique ('multiple point nerve stimulation'). Preliminarily, BoNT/C and BoNT/A dosage was calibrated in a mouse hemidiaphragm neuromuscular junction preparation. Subsequently, 8 volunteers were treated with 3IU of BoNT/C in the extensor digitorum brevis muscle of one foot and 3IU of BoNT/A in the contralateral one. Other 4 subjects were similarly injected at higher doses (10IU of BoNT/C or BoNT/A) to detect a possible dose-toxic effect. RESULTS: In both groups, no statistically significant variations in MUNE counting or single motor unit potential size were detected after 4 months from injections, when it was evident a recovery from the BoNTs blockade. CONCLUSIONS: We conclude that BoNT/C, similarly to BoNT/A, is safe and effective in humans and it could be proposed for a clinical use.

Hemihypoglossal nerve transfer in brachial plexus repair: technique and results.

OBJECTIVE: In multiple avulsions of the brachial plexus, the search for extraplexal donor nerves in the hope of achieving motor neurotization is a major goal. We explored the possibility of using the hypoglossal nerve as a transfer point to reanimate muscles in the upper limb. METHODS: The hypoglossal nerve was used as a donor nerve for neurotization in seven patients with avulsive injuries of the brachial plexus. The surgical technique--an end-to-side microsuture using approximately half of the nerve fascicles--is basically the same as that used in the hypoglossal nerve-facial nerve jump graft, which is a well-known technique in facial nerve reanimation. The recipient nerves were the suprascapular (two patients), the musculocutaneous (one patient), the posterior division of the upper trunk (two patients), and the medial contribution to the median nerve (two patients). RESULTS: In spite of a connection documented by electromyography and selective activation in three of seven patients, the functional results in our patients were extremely disappointing: no patient had an outcome better than M1 in the reinnervated muscles. CONCLUSION: This technique was of no help to the patients and thus has been abandoned at our institution.