CGG/CCG Repeat Expansions in LOC642361/NUTM2B-AS1 in Thai Patients With Oculopharyngodistal Myopathy.

Objectives: This study characterizes oculopharyngodistal myopathy in 4 Thai patients from 3 families with CGG/CCG repeat expansion in LOC642361/NUTM2B-AS1. Methods: Repeat-primed PCR analyzed CGG/CCG repeat size in LOC642361/NUTM2B-AS1 in 4 Thai patients suspected of oculopharyngodistal myopathy (OPDM). Clinical records were reviewed for clinicopathologic features. Results: All patients exhibited strong somatic instabilities of the expanded CGG/CCG repeats, primarily manifesting as oculopharyngeal weakness. Patient 1 had mild finger extensor and intrinsic hand muscle weakness, and although patient 2 lacked limb weakness, both siblings showed electrophysiologic evidence of distal myopathy, indicative of OPDM. Patient 3, the daughter of a sibling with OPDM reported in 2004, lacked limb weakness or leukoencephalopathy on brain MRI. Patient 4, initially misdiagnosed with refractory myasthenia gravis, had generalized muscle weakness. Discussion: While initially characterized as oculopharyngeal myopathy with leukoencephalopathy (OPML) in a Japanese family, our study suggests a stronger association between CGG/CCG expansion in LOC642361/NUTM2B-AS1 and oculopharyngodistal myopathy (OPDM) rather than OPML. The variable presence or absence of leukoencephalopathy further supports OPDM as the predominant clinical manifestation linked to CGG/CCG expansion in LOC642361/NUTM2B-AS1.

Treatment of slow-channel congenital myasthenic syndrome in a Thai family with fluoxetine.

The slow-channel congenital myasthenic syndrome is an autosomal dominant neuromuscular disorder caused by mutations in different subunits of the acetylcholine receptor. Fluoxetine, a common antidepressant and long-lived open-channel blocker of acetylcholine receptor, has been reported to be beneficial in the slow-channel congenital myasthenic syndrome. Here we report a prospective open label study of fluoxetine treatment in some affected members of a Thai family with slow-channel congenital myasthenic syndrome caused by a novel p.Gly153Ala (c.518G > C) mutation in CHRNA1 in the AChR α subunit. These patients showed significant clinical improvement following fluoxetine treatment but their respiratory function responded variably.

Minimal manifestation status and prednisone withdrawal in the MGTX trial.

OBJECTIVE: To examine whether sustained minimal manifestation status (MMS) with complete withdrawal of prednisone is better achieved in thymectomized patients with myasthenia gravis (MG). METHODS: This study is a post hoc analysis of data from a randomized trial of thymectomy in MG (Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone Therapy [MGTX]). MGTX was a multicenter, randomized, rater-blinded 3-year trial that was followed by a voluntary 2-year extension for patients with acetylcholine receptor (AChR) antibody-positive MG without thymoma. Patients were randomized 1:1 to thymectomy plus prednisone vs prednisone alone. Participants were age 18-65 years at enrollment with disease duration less than 5 years. All patients received oral prednisone titrated up to 100 mg on alternate days until they achieved MMS, which prompted a standardized prednisone taper as long as MMS was maintained. The achievement rate of sustained MMS (no symptoms of MG for 6 months) with complete withdrawal of prednisone was compared between the thymectomy plus prednisone and prednisone alone groups. RESULTS: Patients with MG in the thymectomy plus prednisone group achieved sustained MMS with complete withdrawal of prednisone more frequently (64% vs 38%) and quickly compared to the prednisone alone group (median time 30 months vs no median time achieved, p < 0.001) over the 5-year study period. Prednisone-associated adverse symptoms were more frequent in the prednisone alone group and distress level increased with higher doses of prednisone. CONCLUSIONS: Thymectomy benefits patients with MG by increasing the likelihood of achieving sustained MMS with complete withdrawal of prednisone. CLINICALTRIALSGOV IDENTIFIER: NCT00294658. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for patients with generalized MG with AChR antibody, those receiving thymectomy plus prednisone are more likely to attain sustained MMS and complete prednisone withdrawal than those on prednisone alone.

Long-term effect of thymectomy plus prednisone versus prednisone alone in patients with non-thymomatous myasthenia gravis: 2-year extension of the MGTX randomised trial.

BACKGROUND: The Thymectomy Trial in Non-Thymomatous Myasthenia Gravis Patients Receiving Prednisone (MGTX) showed that thymectomy combined with prednisone was superior to prednisone alone in improving clinical status as measured by the Quantitative Myasthenia Gravis (QMG) score in patients with generalised non-thymomatous myasthenia gravis at 3 years. We investigated the long-term effects of thymectomy up to 5 years on clinical status, medication requirements, and adverse events. METHODS: We did a rater-blinded 2-year extension study at 36 centres in 15 countries for all patients who completed the randomised controlled MGTX and were willing to participate. MGTX patients were aged 18 to 65 years at enrolment, had generalised non-thymomatous myasthenia gravis of less than 5 years' duration, had acetylcholine receptor antibody titres of 1·00 nmol/L or higher (or concentrations of 0·50-0·99 nmol/L if diagnosis was confirmed by positive edrophonium or abnormal repetitive nerve stimulation, or abnormal single fibre electromyography), had Myasthenia Gravis Foundation of America Clinical Classification Class II-IV disease, and were on optimal anticholinesterase therapy with or without oral corticosteroids. In MGTX, patients were randomly assigned (1:1) to either thymectomy plus prednisone or prednisone alone. All patients in both groups received oral prednisone at doses titrated up to 100 mg on alternate days until they achieved minimal manifestation status. The primary endpoints of the extension phase were the time-weighted means of the QMG score and alternate-day prednisone dose from month 0 to month 60. Analyses were by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00294658. It is closed to new participants, with follow-up completed. FINDINGS: Of the 111 patients who completed the 3-year MGTX, 68 (61%) entered the extension study between Sept 1, 2009, and Aug 26, 2015 (33 in the prednisone alone group and 35 in the prednisone plus thymectomy group). 50 (74%) patients completed the 60-month assessment, 24 in the prednisone alone group and 26 in the prednisone plus thymectomy group. At 5 years, patients in the thymectomy plus prednisone group had significantly lower time-weighted mean QMG scores (5·47 [SD 3·87] vs 9·34 [5·08]; p=0·0007) and mean alternate-day prednisone doses (24 mg [SD 21] vs 48 mg [29]; p=0·0002) than did those in the prednisone alone group. 14 (42%) of 33 patients in the prednisone group, and 12 (34%) of 35 in the thymectomy plus prednisone group, had at least one adverse event by month 60. No treatment-related deaths were reported during the extension phase. INTERPRETATION: At 5 years, thymectomy plus prednisone continues to confer benefits in patients with generalised non-thymomatous myasthenia gravis compared with prednisone alone. Although caution is appropriate when generalising our findings because of the small sample size of our study, they nevertheless provide further support for the benefits of thymectomy in patients with generalised non-thymomatous myasthenia gravis. FUNDING: National Institutes of Health, National Institute of Neurological Disorders and Stroke.

Randomized Trial of Thymectomy in Myasthenia Gravis.

BACKGROUND: Thymectomy has been a mainstay in the treatment of myasthenia gravis, but there is no conclusive evidence of its benefit. We conducted a multicenter, randomized trial comparing thymectomy plus prednisone with prednisone alone. METHODS: We compared extended transsternal thymectomy plus alternate-day prednisone with alternate-day prednisone alone. Patients 18 to 65 years of age who had generalized nonthymomatous myasthenia gravis with a disease duration of less than 5 years were included if they had Myasthenia Gravis Foundation of America clinical class II to IV disease (on a scale from I to V, with higher classes indicating more severe disease) and elevated circulating concentrations of acetylcholine-receptor antibody. The primary outcomes were the time-weighted average Quantitative Myasthenia Gravis score (on a scale from 0 to 39, with higher scores indicating more severe disease) over a 3-year period, as assessed by means of blinded rating, and the time-weighted average required dose of prednisone over a 3-year period. RESULTS: A total of 126 patients underwent randomization between 2006 and 2012 at 36 sites. Patients who underwent thymectomy had a lower time-weighted average Quantitative Myasthenia Gravis score over a 3-year period than those who received prednisone alone (6.15 vs. 8.99, P<0.001); patients in the thymectomy group also had a lower average requirement for alternate-day prednisone (44 mg vs. 60 mg, P<0.001). Fewer patients in the thymectomy group than in the prednisone-only group required immunosuppression with azathioprine (17% vs. 48%, P<0.001) or were hospitalized for exacerbations (9% vs. 37%, P<0.001). The number of patients with treatment-associated complications did not differ significantly between groups (P=0.73), but patients in the thymectomy group had fewer treatment-associated symptoms related to immunosuppressive medications (P<0.001) and lower distress levels related to symptoms (P=0.003). CONCLUSIONS: Thymectomy improved clinical outcomes over a 3-year period in patients with nonthymomatous myasthenia gravis. (Funded by the National Institute of Neurological Disorders and Stroke and others; MGTX ClinicalTrials.gov number, NCT00294658.).

Long-term effectiveness of acetazolamide on permanent weakness in hyperkalemic periodic paralysis.

Acetazolamide is commonly used as an empirical treatment for inherited periodic paralyses although some patients may develop deleterious effects. We report a 65 year-old man with hyperkalemic periodic paralysis and late-onset permanent weakness in association with the common T704M mutation in α-subunit, skeletal muscle voltage-gated sodium channel gene. He rapidly recovered from weakness after acetazolamide treatment. Magnetic resonance imaging of thighs comparing pre- and post-treatment revealed a significant increase in muscle bulk. The patient has been without any type of weakness for over 6 years. This data show the remarkable benefit of acetazolamide on permanent weakness of hyperkalemic periodic paralysis in association with the T704M mutation.

Prevalence, clinical features and treatment outcomes of patients with myasthenia gravis positive for antibodies to muscle-specific kinase in Thailand.

A small but variable subgroup of patients with myasthenia gravis (MG) who have antibodies to muscle-specific kinase (MuSKAb-MG) can present with distinct phenotypes and are often treatment-resistant. The prevalence, clinical phenotypes and outcomes of treatment of patients with MuSKAb-MG in Thailand were determined. Eight (16.3%) of the 49 patients with generalized MG who were negative for acetylcholine receptor antibodies (AChRAb) were positive for muscle-specific kinase antibodies. Most patients had predominant oculobulbar features and respiratory failure occurred in three. At follow up, three out of the seven patients who underwent thymectomy were in complete stable remission and four had improved and were on reduced immunosuppression medication, suggesting a possible benefit of thymectomy.

Electrophysiological and immunological study in myasthenia gravis: diagnostic sensitivity and correlation.

OBJECTIVE: To determine the diagnostic sensitivity of repetitive nerve stimulation (RNS), single fiber electromyography (SFEMG) and acetylcholine receptor antibody (AChRAb) in myasthenia gravis (MG), and to compare the degree of SFEMG abnormality between ocular and generalized MG and between seronegative and seropositive patients. METHODS: The sensitivities of RNS, SFEMG and AChRAb were estimated. SFEMG abnormality was compared between ocular and generalized MG and between seronegative and seropositive patients. RESULTS: Abnormal RNS, abnormal SFEMG and AChRAb were detected in 62%, 93% and 38% of 42 ocular, and 80%, 99% and 73% of 70 generalized cases, respectively. The degree of SFEMG abnormality was significantly greater in the generalized than ocular patients and was significantly greater in the seropositive than seronegative patients in both extensor digitorum communis and orbicularis oculi muscles. CONCLUSION: SFEMG is a very sensitive and useful test for MG. A correlation between SFEMG abnormality and clinical phenotype or severity and between SFEMG abnormality and AChRAb seropositivity was demonstrated. SIGNIFICANCE: The sensitivities of RNS, SFEMG and AChRAb in the diagnosis of MG were documented. The differences in severity between the ocular and generalized MG and between the seronegative and seropositive MG were confirmed and quantitatively determined by SFEMG.

Phenotypic heterogeneity in a large Thai slow-channel congenital myasthenic syndrome kinship.

The slow-channel congenital myasthenic syndrome (SCCMS) is an autosomal dominant neuromuscular disorder caused by mutations in different subunits of the acetylcholine receptor (AChR). We here report our clinical findings in three generations of a large Thai kinship suffering from SCCMS and trace the disease to the p.Gly153Ser mutation in the AChR α subunit. The same mutation had previously been reported only in Caucasian but not in Asian patients. The clinical features include ptosis, ophthalmoparesis, and weakness of the cervical and finger extensor muscles as well as marked phenotypic heterogeneity.

Glioblastoma multiforme at the corpus callosum with spinal leptomeningeal metastasis.

Glioblastoma multiforme (GBM) often occurs in the supratentorial white matter including corpus callosum. However, spinal leptomeningeal metastasis in cases of supratentorial GBM has been reported to be rare and there is usually a long interval between the cerebral lesion and the spinal seeding. We report here a case of GBM at the corpus callosum and other parts of the brain with simultaneous manifestation of spinal leptomeningeal seeding. The patient exhibited an abnormal motor behavior of the left hand as mirror movement when the right hand was performing a unimanual task (diagonistic dyspraxia) which is a sign of lesion of the posterior part and splenium of the corpus callosum. There were also signs of peripheral nerve or nerve root involvement suggestive of spinal metastasis without any sensory symptoms. He died 3 months after the onset of the symptoms confirming the poor prognosis and short survival time in cases with spinal leptomeningeal metastasis reported previously. The cerebral GBM with spinal seeding was disclosed at autopsy.

Survival analysis for respiratory failure in patients with food-borne botulism.

INTRODUCTION: Botulism is a rare presynaptic neuromuscular junction disorder caused by potent toxins produced by the anaerobic, spore-forming, Gram-positive bacterium Clostridium botulinum. Food-borne botulism is caused by the ingestion of foods contaminated with botulinum toxin. In March 2006, there was a large outbreak of food-borne botulism associated with the ingestion of home-canned bamboo shoots in Thailand. The survival analyses for respiratory failure in these patients were studied and are reported here. METHODS: A prospective observational cohort study was conducted on this outbreak. The primary outcome of interest was the time to respiratory failure. The secondary outcome was the time to weaning off ventilator. The prognostic factors associated with respiratory failure and weaning off ventilator are presented. RESULTS: A total of 91 in-patients with baseline clinical characteristics were included. Most cases first presented with gastrointestinal symptoms followed by neurological symptoms, the most striking of which being difficulty in swallowing. Common clinical features included ptosis, ophthalmoplegia, proximal muscle weakness, pupillary abnormality, and respiratory failure. Forty-two patients developed respiratory failure requiring mechanical ventilation and the median duration on ventilator was 14 days. The median length of hospital stay for all patients was 13.5 days. Difficulty in breathing, moderate to severe ptosis, and dilated and fixed pupils were associated with respiratory failure. Among patients who were on ventilators, a short incubation period and pupillary abnormality were associated with a longer period of mechanical ventilation. All patients had antitoxin injection and there was no mortality in this outbreak. CONCLUSION: The history of difficult breathing and the findings of moderate to severe ptosis and pupillary abnormality were associated with severe illness and respiratory failure. A long incubation time was associated with a better prognosis. Although botulism is a potentially fatal disease, there was no mortality in this outbreak. All patients had antitoxin injection and good intensive care that resulted in good clinical outcomes.

Cerebral aspergillosis and cerebral candidiasis; a retrospective analysis of clinicopathologic features in Ramathibodi Hospital.

OBJECTIVE: Determine and compare the clinicopathological findings of cerebral aspergillosis with cerebral candidiasis. MATERIAL AND METHOD: The medical records with cerebral aspergillosis and cerebral candidiasis in Ramathibodi Hospital between January 1997 and December 2008 were analyzed. The criterion for the diagnosis of cerebral aspergillosis and cerebral candidiasis was the evidence of fungal elements from histopathologic section. The age, gender neurological manifestations, duration of symptom, associated underlying disease, predisposing risk factor, laboratory data, extent of systemic organ involvement and treatment outcome were analyzed. RESULTS: The present study included cerebral aspergillosis (n = 41) and candidiasis (n = 15). There were 23 male and 33 female patients. The mean and median ages at diagnosis were 39.7 and 45 years, respectively (range, 1 month to 87 years). The clinical presentations included alteration of consciousness (69.6%), fever (60.7%), weakness of the extremity (14.3%), cranial nerve palsy (12.5%), headache (12.59%) and seizure (5.4%). One third of the cases had underlying hematologic malignancy. The cerebral aspergillosis and cerebral candidiasis were associated with corticosteroids treatment in 32.1%. The frequent associated sites of fungal infection included the lungs (73.2%), alimentary tract (33.9%) and sinonasal tract (19.6%). CONCLUSION: A diagnosis of cerebral aspergillosis and cerebral candidiasis requires a high index of suspicion especially in immunocompromised patients who presented with alteration of consciousness, fever, focal neurological deficit, headache, and seizure. The patients with cerebral aspergillosis and cerebral candidiasis manifest with similar clinicopathologic features. However, the sinonasal tract infection and abscess formation are more common in cerebral aspergillosis. Associated alimentary tract infection is commonly seen in cerebral candidiasis.

Congestive heart failure with rhabdomyolysis and acute renal failure in a manifesting female carrier of Duchenne muscular dystrophy with duplication of dystrophin gene.

We report a 69-year-old woman who presented with dyspnea, orthopnea, and acute renal failure. She also had proximal muscle weakness suggestive of muscle disease. Her symptoms were alleviated by induced dieresis, although there was high-serum creatine kinase. Investigations for any possible etiologies of rhabdomyolysis were all negative. An X-linked recessive muscle disease was highly suspicious in view of the fact that both of her sons had suffered from muscle disease and died of respiratory failure at the ages of 22 and 29, respectively. Her muscle biopsy showed mosaic pattern with dystrophin antibody against amino-terminal, carboxy-terminal, and rod domain. Her DNA study revealed heterozygous duplication at exon 1 to 6 of the dystrophin gene as well. Therefore, she is a manifesting carrier of dystrophinopathy who was first diagnosed in late adulthood with congestive heart failure, acute episode of spontaneous rhabdomyolysis, and acute renal failure.

Novel DYSF mutations in Thai patients with distal myopathy.

Dysferlinopathy refers to a variety of autosomal recessive, skeletal muscle disorders due to the mutations of dysferlin-encoding gene, DYSF. It encompasses limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), distal myopathy with anterior tibial onset (DMAT), isolated hyperCKemia, rigid spine syndrome and congenital muscular dystrophy. Herein, we report five Thai patients with distal myopathy due to dysferlinopathy including four MM and one DMAT patients. Muscle biopsy from one MM patient depicted numerous ring fibers which is an atypical finding in dysferlinopathy. Mutation analysis of DYSF revealed novel compound heterozygous mutations of p.Tyr309X and c.236+1G>T in two related MM patients, known homozygous mutations, p.Arg89X and p.Gln176X, in two MM patients and a heterozygous missense mutation, p.Arg555Trp, in a DMAT patient. Most of the previously reported DMAT patients were Hispanic. To the best of our knowledge, this is the first report of genetically confirmed patients with dysferlinopathy in Thailand.

Electrodiagnosis of botulism and clinico-electrophysiological correlation.

OBJECTIVE: An electrophysiological study can help to confirm the diagnosis of botulism. This study was aimed at validating a simple and reliable electrodiagnostic test and at correlating the findings with clinical severity. METHODS: Pre- and post-exercise single supramaximal stimulations (SSSs) were performed in 63 patients with botulism. The sensitivity and specificity of amplitude of compound muscle action potential (CMAP) and percentage increment (PI) of SSS were determined. These two parameters were then correlated with respiratory failure. The relationship between the amplitude of CMAP and PI was also studied. RESULTS: SSS with a PI of 25% showed a sensitivity of 95.2% and a specificity of 100% in association with botulism. The area under the receiver operating characteristic (ROC) curve of CMAP and PI was associated with the respiratory failure by 0.7 and 0.6, respectively. An inverse relationship between the amplitude of CMAP and PI was also demonstrated. CONCLUSIONS: SSS is sensitive and specific in the diagnosis of botulism. There was some correlation of the findings with clinical severity. The inverse relationship between the amplitude of CMAP and PI reflects the pathophysiology of this disorder. SIGNIFICANCE: This study has validated SSS as being a simple and reliable electrodiagnostic test for botulism.

Idiopathic hypertrophic cranial pachymeningitis.

Idiopathic hypertrophic cranial pachymeningitis is a rare chronic inflammatory process of unknown origin that can cause neurological deficits owing to thickening of the dura. Patients with this condition commonly present with cranial neuropathy accompanied by localized headache. The clinical features, neuroimaging findings, histopathological features and treatment outcomes for three patients with this condition are reported here. The first patient presented with subacute dull headache in the left temporal area followed by left abducens nerve palsy. The second patient suffered from a cranial nerve IX-XII lesion accompanied by an occipital headache and the third patient presented with left optic neuropathy and mild headache in the frontal area. In all patients, MRI of the brain revealed prominent dural thickening, and histopathological study of the dura revealed chronic inflammatory cell infiltration. Combined therapy with corticosteroid and immunosuppressive drugs was effective, resulting in almost complete resolution of the symptoms and signs, except for visual impairment in one patient.

Relative fatigability of muscles in response to repetitive nerve stimulation in myasthenia gravis.

BACKGROUND: Repetitive nerve stimulation (RNS) plays an important role in the diagnosis of myasthenia gravis (MG). Technically, this test can be more easily performed on distal muscles than proximal muscles. On the other hand, proximal muscles have been shown to be more easily fatigued or more sensitive than the distal ones. OBJECTIVE: Evaluate the relative fatigability of different muscles in response to RNS in ocular and generalized MG patients. MATERIAL AND METHOD: Two hundred patients with 44 ocular MG and 156 generalized MG were studied The relative fatigability of each muscle was calculated as percentage of cases with abnormal response. A decrement of 10% or more of the amplitude of the compound muscle action potentials was considered abnormal. RESULT: The cases with abnormal response of adductor digiti minimi, anconeus, trapezius, nasalis and orbicularis oculi were 17%, 50%, 55%, 62%, 66% in ocular MG and 53%, 77%, 79%, 85%, 79% in generalized MG respectively. These results showed that in generalized MG the response in all the muscles was more frequently abnormal and was fatigable in a more comparable degree, whereas in ocular MG, the facial muscles were more often abnormal than the limb muscles. CONCLUSION: The abnormal response because of fatigability was more widespread in generalized MG whereas facial muscles were relatively more sensitive in ocular MG. This finding may be useful for the selection of the muscles to be tested in RNS especially in ocular MG.

POEMS syndrome with venous sinus thrombosis and visual failure: a case report.

POEMS (polyneuropathy, organomegaly, endocrinopathy, M protein and skin changes) syndrome is a multisystem disorder associated with plasma cell dyscrasia. Other clinical signs include clubbing of the fingers, edema, papilledema etc. Although papilledema and increased intracranial pressure are common features, their causes or pathophysiology have been uncertain. The authors report here a 16-year-old Thai patient with these features who also suffered from venous sinus thrombosis and visual failure which have never been reported before. The former is considered to be one of the possible causes of the intracranial hypertension and visual failure. MRI of the brain and optic nerve revealed enhancement and swelling of the optic nerve sheaths and optic discs. MRV findings were compatible with chronic veno-occlusive disease. Bone marrow aspiration and biopsy demonstrated an increase of aggregates of intermediate and mature plasma cells. The CSF pressure was markedly elevated. His clinical condition continued to deteriorate and he expired 3 years and 5 months from the onset of his illness. Although, overproduction of vascular endothelial growth factor has been reported and is being considered to be the possible cause of vascular hyperpermeability, the chronic venous sinus thrombosis may play an important role in the pathogenesis of intracranial hypertension and visual failure.

Polyneuropathy from thiamin deficiency associated with thyrotoxicosis.

Polyneuropathy from thiamin deficiency can occur in persons who consume a diet consisting mainly of polished rice with low protein and thiamin content in the setting of excessive physical activity or hypermetabolic states. The authors report here a 17-year-old fisherman who presented with a 3-month history of symptoms and signs consistent with polyneuropathy. There were also clinical features of thyrotoxicosis which was confirmed by thyroid function test. His dietary intake consisted mainly of polished rice and fish both of which contain a small amount of thiamin. This could not cope with his hypermetabolic condition from thyrotoxicosis resulting in thiamin deficiency with polyneuropathy.