Does oral salbutamol improve fatigue in multiple sclerosis? A pilot placebo-controlled study.

BACKGROUND: Because MS-related fatigue could be associated with enhanced proinflammatory cytokine production, drugs with immunomodulatories properties, such as salbutamol, may represent an alternative treatment. We aimed to evaluate the effect of salbutamol on MS-related fatigue. METHODS: Thirty patients with relapsing-remitting MS who were between 18 and 69 years old, and suffering from fatigue, were evaluated with the Fatigue Severity Scale (FSS) and the Brazilian version of the neurological fatigue index for multiple sclerosis (NFI/MS-BR). They received salbutamol 2 mg twice a day or a placebo in a pilot randomized, double-masked placebo-controlled trial. The primary outcome was the change in the FSS score at the end of 90 days. The secondary outcome was the efficacy, represented by changes in their scores on the NFI/MS-BR subdomains (in the same period) and the Expanded Disability Status Scale (EDSS) at the end of 90 days. RESULTS: Thirty subjects were allocated to receive either salbutamol (14) or a placebo (16). There was no superiority of salbutamol over the placebo in the FSS outcome at 30 (p ==0.498), 60 (p = 0.854) and 90 (p = 0.240) days. There was no a significant decrease in the proportion of patients with severe or moderate fatigue in the salbutamol group at the end of the follow-up. The scores on the NFI/MS-BR and its subscales did not improve significantly with treatment. No significant difference was observed in the EDSS outcome (p = 0.313). No serious adverse events were found. An increase in heart rate was evident in the salbutamol group only in the first 30 days, but without statistical significance in relation to placebo (p = 0.077). CONCLUSION: Treatment with salbutamol does not improve fatigue in patients with relapsing-remitting MS.

NMO-IgG positive neuromyelitis optica in a patient with myasthenia gravis but no thymectomy.

Here we report on a 44-year old woman presenting with both myasthenia gravis (MG) and neuromyelitis optica (NMO). MRI showed transverse myelitis extending from C2 to T4, multifocal demyelinating lesions in the supratentorial white matter, and left optic neuritis. Serological analysis demonstrated antibodies to acetylcholine receptors as well as NMO-IgG. To our knowledge, this is the first case of NMO-IgG positive NMO in a patient with MG but no history of thymectomy or immunosuppression.

Cerebellar ataxia in non-paraneoplastic Lambert-Eaton myasthenic syndrome.

Lambert-Eaton myasthenic syndrome (LEMS) is an immune-mediated disorder of the neuromuscular junction that rarely is associated with cerebellar ataxia (CA). We describe two patients with non-paraneoplastic LEMS associated with CA who showed high levels of anti-P/Q-type voltage-gated calcium channels antibodies in the serum and cerebrospinal fluid, and reduced CMAP with increment after brief maximum voluntary contraction in electrophysiological studies. We suggest that LEMS should be considered in the differential diagnosis of patients with CA.

Dandy-Walker syndrome in adult mimicking myasthenia gravis.

The Dandy-Walker syndrome (DWS) is a rare posterior fossa malformation. The DWS can occur associated with other brain or systemic malformations, but ocular abnormalities in this disease are rare and clinical findings mimicking myasthenia gravis have not been described to date. We report a 23-year-old woman who presented mild limitation of the ocular movements with progressive palpebral ptosis, which changed in intensity during the day. The investigation showed negative anti-acetylcholine receptor antibody, repetitive nerve stimulation and "Tensilon test", but the brain magnetic resonance image reveals DWS with hydrocephalus associated with callosal dysgenesis. The characteristic of disease, clinical manifestations and pathologic features, specially the clinical evaluation of ocular abnormalities in suspicion of DWS, including the MG in differential diagnosis are discussed.

Menkes' disease: case report.

Menkes disease is a rare neurodegenerative disorder due to an intracellular defect of a copper transport protein. We describe a 7 months male patient who presented with seizures, hypoactivity and absence of visual contact. The investigation disclosed pilli torti and thrycorrexis nodosa in the hair, low serum levels of both copper and ceruloplasmin, brain magnetic resonance study showed atrophy and white matter hypointensities on T1-weighted images, electroencephalogram reveals moderate background activity disorganization and epileptiform activity, and muscle biopsy with type 2 fiber atrophy. The clinical, laboratorial, genetic, muscle biopsy and neurophysiological findings in Menkes disease are discussed.

A novel missense mutation pattern of the GCH1 gene in dopa-responsive dystonia.

Dopa-responsive dystonia (DRD) is an inherited metabolic disorder now classified as DYT5 with two different biochemical defects: autosomal dominant GTP cyclohydrolase 1 (GCH1) deficiency or autosomal recessive tyrosine hydroxylase deficiency. We report the case of a 10-years-old girl with progressive generalized dystonia and gait disorder who presented dramatic response to levodopa. The phenylalanine to tyrosine ratio was significantly higher after phenylalanine loading test. This condition had two different heterozygous mutations in the GCH1 gene: the previously reported P23L mutation and a new Q182E mutation. The characteristics of the DRD and the molecular genetic findings are discussed.

Clinical follow-up of pregnancy in myasthenia gravis patients.

This study aimed to analyze the outcome and impact of pregnancy in women with myasthenia gravis (MG). Obstetric and clinical data were retrospectively analyzed before, during and after pregnancy. Predictors of outcome were studied. We included 35 pregnancies from 21 MG patients. In the course of MG symptoms in 30 pregnancies with live births, 50% deteriorated (mainly during the second trimester, p = 0.028), 30% improved, and 20% remained unchanged. The deterioration group had more frequent abnormal repetitive nerve stimulation (RNS) (p = 0.028) and lower myasthenia gravis composite (MGC) scores (p = 0.045) before pregnancy. The improvement group was associated with higher MGC scores (p = 0.012) before pregnancy. The no-change group was associated with longer duration of MG (p = 0.026) and normal RNS (p = 0.008) before pregnancy. The course of MG in the second pregnancy was different from that in the previous pregnancy in 65.3% of cases. Obstetric complications were reported in 20 pregnancies; the most common was preterm premature rupture of membranes (PPROM) (25.8%), and the most severe were abortion (11.4%) and fetal death (2.9%). Most of the patients delivered via caesarean section (66.7%). Spinal anesthesia was performed in 73.3%. Transient neonatal myasthenia gravis occurred in 12.9% of live-born infants, and no predictors were found. In conclusion, severity and duration of MG, RNS and treatment influence MG and pregnancy. Pregnant MG patients have greater rates of PPROM and caesarean delivery. Our data suggest that duration of MG, MGC and RNS before pregnancy may be useful in helping to predict the course of MG during pregnancy.

Novel synaptobrevin-1 mutation causes fatal congenital myasthenic syndrome.

OBJECTIVE: To identify the molecular basis and elucidate the pathogenesis of a fatal congenital myasthenic syndrome. METHODS: We performed clinical electrophysiology studies, exome and Sanger sequencing, and analyzed functional consequences of the identified mutation. RESULTS: Clinical electrophysiology studies of the patient revealed several-fold potentiation of the evoked muscle action potential by high frequency nerve stimulation pointing to a presynaptic defect. Exome sequencing identified a homozygous c.340delA frameshift mutation in synaptobrevin 1 (SYB1), one of the three SNARE proteins essential for synaptic vesicle exocytosis. Analysis of both human spinal cord gray matter and normal human muscle revealed expression of the SYB1A and SYB1D isoforms, predicting expression of one or both isoforms in the motor nerve terminal. The identified mutation elongates the intravesicular C-terminus of the A isoform from 5 to 71, and of the D isoform from 4 to 31 residues. Transfection of either mutant isoform into bovine chromaffin cells markedly reduces depolarization-evoked exocytosis, and transfection of either mutant isoform into HEK cells significantly decreases expression of either mutant compared to wild type. INTERPRETATION: The mutation is pathogenic because elongation of the intravesicular C-terminus of the A and D isoforms increases the energy required to move their C-terminus into the synaptic vesicle membrane, a key step for fusion of the synaptic vesicle with the presynaptic membrane, and because it is predicted to reduce expression of either isoform in the nerve terminal.

Salbutamol therapy in congenital myasthenic syndrome due to DOK7 mutation.

INTRODUCTION: Salbutamol is a selective B2-adrenergic agonist, which has previously been described to be associated with partial improvement of myasthenia gravis and congenital myasthenic syndromes (CMS). In this study, we analyzed the effect of salbutamol in five patients with Dok-7 CMS. METHODS: We studied 5 patients (2 male and 3 female), with a mean age of 27±11.06 years, who harbored c.1124_1127dupTGCC, p.G64R and/or p.S45L mutations in DOK7 gene. Salbutamol was given at a dose of 2mg three times daily (6 mg/day) to all patients. The response was assessed by QMG score at baseline, 3, 6, 9 and 12 months; ADL-MG score and 6 minute walk test at baseline and after 12 months during follow-up clinic visits. Side effect profile of salbutamol was also evaluated. RESULTS: We noted an increasingly positive response as measured by the QMG score after 3 months of salbutamol treatment. Improvement in specific subcomponents of the QMG score such as leg outstretched in 45° supine was most marked. In ADL-MG scores and 6 minute walk test, comparison between baseline and after 12 months revealed a clear beneficial response. Salbutamol was well tolerated in all patients. CONCLUSIONS: Salbutamol is an effective treatment in Dok-7 CMS. This study provides class IV evidence that salbutamol given at a dose 6 mg/day improves function as measured by the QMG score, ADL-MG score and 6 minute walk test.

Electrophysiological characteristics in four patients from Brazil with stiff person syndrome.

Stiff person syndrome (SPS) is a rare immune-mediated disorder of the central nervous system characterized by muscle rigidity and episodic muscle spasms. The diagnosis of SPS is based on electrophysiological studies. We analyzed the electrophysiological features in four patients from Brazil who fulfilled the clinical criteria for SPS. The most common electrophysiological abnormalities were continuous motor unit activity, co-contracting, and the presence of the cutaneomuscular reflex. Despite all patients having clinical characteristics of SPS during the disease, no patient met all the electrophysiological criteria for SPS even after repeat electrophysiological studies. This shows that a diagnosis of SPS should not be restricted to patients with all the classic electrophysiological changes but should be considered in the presence of one or some of those changes.

Neurological disorders associated with glutamic acid decarboxylase antibodies: a Brazilian series.

Neurological disorders associated with glutamic acid decarboxylase (GAD) antibodies are rare pleomorphic diseases of uncertain cause, of which stiff-person syndrome (SPS) is the best-known. Here, we described nine consecutive cases of neurological disorders associated with anti-GAD, including nine patients with SPS and three cases with cerebellar ataxia. Additionally, four had hypothyroidism, three epilepsy, two diabetes mellitus and two axial myoclonus.

Non-paraneoplastic Lambert-Eaton myasthenic syndrome: a brief review of 10 cases.

Lambert-Eaton myasthenic syndrome (LEMS) is an immune-mediated disorder of the presynaptic neuromuscular transmission, which more frequently occurs as the remote effect of a neoplasm, in the paraneoplastic form (P-LEMS), or in a non-paraneoplastic form (NP-LEMS); but few studies describe the clinical features of NP-LEMS. We analyzed the clinical manifestations, laboratory findings, electrophysiological studies, and treatment responses in ten Brazilian patients suffering from NP-LEMS. The mean age was 41.5 years. More often neurological findings were hyporeflexia or areflexia with a post-exercise improvement. Treatment response occurred with pyridostigmine, guanidine, prednisone, azathioprine, and cyclosporine; but not response was observed after intravenous immunoglobulin and plasma exchange. Age at onset, clinical manifestations, and electrophysiological abnormalities can help more in the diagnosis than serum antibodies; the symptomatic treatment with pyridostigmine was effective; and the immunosuppressive treatment with prednisone, azathioprine, or cyclosporine was more beneficial than plasma exchange or intravenous immunoglobulin treatment.

A missense mutation in the Kv1.1 voltage-gated potassium channel-encoding gene KCNA1 is linked to human autosomal dominant hypomagnesemia.

Primary hypomagnesemia is a heterogeneous group of disorders characterized by renal or intestinal magnesium (Mg2+) wasting, resulting in tetany, cardiac arrhythmias, and seizures. The kidney plays an essential role in maintaining blood Mg2+ levels, with a prominent function for the Mg2+-transporting channel transient receptor potential cation channel, subfamily M, member 6 (TRPM6) in the distal convoluted tubule (DCT). In the DCT, Mg2+ reabsorption is an active transport process primarily driven by the negative potential across the luminal membrane. Here, we studied a family with isolated autosomal dominant hypomagnesemia and used a positional cloning approach to identify an N255D mutation in KCNA1, a gene encoding the voltage-gated potassium (K+) channel Kv1.1. Kv1.1 was found to be expressed in the kidney, where it colocalized with TRPM6 along the luminal membrane of the DCT. Upon overexpression in a human kidney cell line, patch clamp analysis revealed that the KCNA1 N255D mutation resulted in a nonfunctional channel, with a dominant negative effect on wild-type Kv1.1 channel function. These data suggest that Kv1.1 is a renal K+ channel that establishes a favorable luminal membrane potential in DCT cells to control TRPM6-mediated Mg2+ reabsorption.

A novel missense mutation in the caveolin-3 gene in rippling muscle disease.

Rippling muscle disease (RMD) is a benign myopathy with symptoms and signs of muscular hyperirritability. We report a 17-year-old patient who presented with muscular hypertrophy, local mounding on percussion, and a rippling phenomenon. Needle electromyography showed electrical silence during the rippling phenomenon. Muscle protein immunohistochemical analysis showed a partial deficiency of caveolin-3. Molecular analysis revealed a novel heterozygous A>C transition at nucleotide position 140 in exon 2 of the caveolin-3 gene. We associated this novel mutation with RMD.

Neurological disorders associated with glutamic acid decarboxylase antibodies: a Brazilian series / Distúrbios neurológicos associadas a anticorpos anti-GAD (descarboxilase do ácido glutâmico): uma série de casos brasileira

Neurological disorders associated with glutamic acid decarboxylase (GAD) antibodies are rare pleomorphic diseases of uncertain cause, of which stiff-person syndrome (SPS) is the best-known. Here, we described nine consecutive cases of neurological disorders associated with anti-GAD, including nine patients with SPS and three cases with cerebellar ataxia. Additionally, four had hypothyroidism, three epilepsy, two diabetes mellitus and two axial myoclonus.

Distúrbios neurológicos associados com anticorpos anti-GAD são doenças pleomórficas, raras, de causa incerta, das quais a rigidez muscular espasmódica (SPR) é a mais conhecida. Neste estudo, descrevemos nove casos consecutivos de distúrbios neurológicos associados com a presença de anticorpos anti-GAD, incluindo nove pacientes com SPR e três casos com ataxia cerebelar. Adicionalmente, foram encontrados quatro casos com hipotireoidismo, três com epilepsia, dois com diabetes mellitus e dois casos com mioclonia axial.