Neuromyelitis Optica Spectrum Disorder Preceded by Myotonic Myopathy

Neuromyelitis optica spectrum disorder (NMOSD) is generally known as selective involvement of central nervous system. However, in recent years, some evidences have been found that NMOSD invades other peripheral organs. Especially, skeletal muscle involvement of NMOSD has been documented scantily and further studies must be required. Here, we describe a patient who first had generalized fatigue, mild weakness, and myalgia with increased level of serum creatine kinase and was finally diagnosed with myopathy associated with NMOSD.

Paramyotonia congenita caused by a novel mutation of SCN4A gene in a Chinese family / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect SCN4A gene mutation in a pedigree with paramyotonia congenita in order to facilitate genetic counseling and assisted reproduction.</p><p><b>METHODS</b>Clinical data of the family was collected. DNA was extracted from peripheral blood samples. Potential mutation of the SCN4A gene was screened using PCR-Sanger sequencing. Potential mutation was detected in 3 affected relatives, 4 unaffected relatives and 100 unrelated healthy controls. Bioinformatics software was used to predict the effect of mutation on the protein function and conservation of the sequence at the mutation site across various species.</p><p><b>RESULTS</b>A novel missense mutation c.4427T>C (p.Met1476Thr) was detected in the exon 24 of the SCN4A gene in the proband and other 3 affected relatives, but not in 4 unaffected relatives and 100 unrelated controls. Bioinformatic analysis indicated that the codon is highly conserved across various species, and that the mutation has caused damage to the structure and function of SCN4A protein.</p><p><b>CONCLUSION</b>The c.4427 T>C (p.Met1476Thr) mutation of the SCN4A gene may contribute to the paramyotonia congenita. Detection of SCN4A gene mutation is an effective method for the diagnosis of paramyotonic congenita.</p>

Epidural anesthesia for a lumbar discectomy in a patient with paramyotonia congenita: A case report

Paramyotonia congenita is a rare hereditary skeletal muscle disease characterized by exercise- or cold-induced myotonia. Anesthesiologists should make any efforts to prevent perioperative myotonic attack and muscle weakness in patients with this kind of disorder. Specifically, the administration of depolarizing muscle relaxants should be avoided and serum potassium level as well as body temperature should be carefully managed. The present report describes our experiences with successful epidural anesthesia in a patient with paramyotonia congenita who underwent a lumbar discectomy.

Association between neurological and rheumatological manifestations in vitamin D deficiency and vitamin D levels

We aimed to investigate the associations between the neurological manifestations of vitamin D deficiency and bone profile as well as the levels of 25-hydroxyvitamin D. We conducted a case series on patients with vitamin D deficiency who were followed up at King Abdulaziz Medical City, Jeddah between January 2010 and December 2011. We collected patients' demographic data and gathered information on etiological factors for vitamin D deficiency as well as clinical presentations [typical, neurological and rheumatological] and radiological findings. The t-test was used to determine whether there was an association between the neurological manifestations of vitamin D deficiency and vitamin D levels and bone profile. We enrolled 60 patients with vitamin D deficiency. Of these, 44 [73.3%] had neurological presentations, namely progressive muscle weakness and proximal weakness, which was observed more often than distal weakness. In addition, gait disturbances were observed in 61.7% of all patients with neurological and rheumatological presentations. There was no significant association between neurological and rheumatological manifestations and bone profile or vitamin D levels. We found a significant association between difficulty in walking and the levels of serum calcium and phosphate [P = 0.043 and 0.037, respectively]. Neurological and rheumatologic manifestations of vitamin D deficiency are not associated with 25-hydroxyvitamin D levels or bone profile

Clinical Diversity of SCN4A-Mutation-Associated Skeletal Muscle Sodium Channelopathy

BACKGROUND AND PURPOSE: Mutations of the skeletal muscle sodium channel gene SCN4A, which is located on chromosome 17q23-25, are associated with various neuromuscular disorders that are labeled collectively as skeletal muscle sodium channelopathy. These disorders include hyperkalemic periodic paralysis (HYPP), hypokalemic periodic paralysis, paramyotonia congenita (PMC), potassium-aggravated myotonia, and congenital myasthenic syndrome. This study analyzed the clinical and mutational spectra of skeletal muscle sodium channelopathy in Korean subjects. METHODS: Six unrelated Korean patients with periodic paralysis or nondystrophic myotonia associated with SCN4A mutations were included in the study. For the mutational analysis of SCN4A, we performed a full sequence analysis of the gene using the patients' DNA. We also analyzed the patients' clinical history, physical findings, laboratory tests, and responses to treatment. RESULTS: We identified four different mutations (one of which was novel) in all of the patients examined. The novel heterozygous missense mutation, p.R225W, was found in one patient with mild nonpainful myotonia. Our patients exhibited various clinical phenotypes: pure myotonia in four, and PMC in one, and HYPP in one. The four patients with pure myotonia were initially diagnosed as having myotonia congenita (MC), but a previous analysis revealed no CLCN1 mutation. CONCLUSIONS: Clinical differentiating between sodium-channel myotonia (SCM) and MC is not easy, and it is suggested that a mutational analysis of both SCN4A and CLCN1 is essential for the differential diagnosis of SCM and MC.

Carcinoma escamocelular intracerebral originario de un quiste epidermoide: reporte de un caso / Sgnamous carcinoma arising in a intracerebral epidermoid cyst

La frecuencia del quiste epidermoide es baja, su transformación maligna lo es aún más. Se presenta el caso de un quiste epidermoide parcialmente resecado que ocho años mas tarde cursó como carcinoma escamocelular

Paramiotonía congénita una / Congenital paramyotonia a practical approach

En éste artículo se describen los diferentes tipos del miotonía, entidades relacionadas, fisiopatología y manejo, haciendo énfasis en la paramiotonía congénita

Osteomalacic Myopathy due to celiac disease

Celiac disease is a gluten-sensitive enteropathy characterized by malabsorption resulting from inflammatory injury to the mucosa of the small intestine. It is well known to be associated with a variety of neurological disorders including epilepsy, myopathy, neuropathy and ataxia. The nature of this association is unclear. Although osteomalacia secondary to vitamin D deficiency is a recognized complication of celiac disease, however, severe osteomalacic myopathy as the only presentation of celiac disease is extremely rare. We present 2 interesting cases of osteomalacic myopathy secondary to celiac disease, which were treated successfully with full recovery. An important and unique observation was the brisk reflexes noticed in both patients. The mechanism behind this phenomenon is not well understood. Work-up for celiac disease is warranted in any young patient that presents with myopathy

Genetics of Channelopathy: Familial Periodic Paralysis

Familial periodic paralysis (FPP) is inherited as a dominant trait, and the intermittent failure to maintain the skeletal muscle resting potential is due to mutations in the genes coding for the voltage-gated ion channels. Because several variants of FPP have been delineated on the bases of clinical features, the expectation was that these variants might be due to involvement of different classes of ion channels. The reality of the situation has proven to be more complicated. Mutation-induced defects in the same channel may give rise to diverse phenotypes (phenotypic heterogeneity) and, conversely, mutation in different channel genes may produce a common phenotype (genetic heterogeneity). Regardless of which type of ion channel is defective, the final common pathway is the depolarization-induced loss of muscle excitability; gain-of-function defect in voltage-gated Na channel may cause myotonia, periodic paralysis or both, clinical features of hyperkalemic periodic paralysis and paramyotonia congenita, and loss-of-function defects in voltage-gated Na and Ca channel and K channel may be responsible for periodic paralysis, cardiac arrhythmia or both in hypokalemic periodic paralysis or Andersen's syndrome, respectively. This review focuses on the clinical features, molecular genetic defects, and pathophysiologic mechanisms that underlie FPP.

A Case of Acute Colchicine-induced Myopathy with Myotonia in Behcet Disease

Colchicine has been used in the treatment of autoimmune diseases such as Behcet disease. Long-term use of colchicine can cause vacuolar myopathy on rare occasions. We report colchicine-induced myopathy with myotonia in Behcet disease. A 34-year-old man with Behcet disease presented progressive proximal weakness, myalgia, and difficulty in relaxation of grip after increasing the dosage of colchicine. Electrophysiological findings showed myotonic myopathy. Muscle biopsy revealed vacuolar myopathy. His symptoms were resolved with the discontinuation of colchicine.

A Korean Family with Arg1448Cys Mutation of SCN4A Channel Causing Paramyotonia Congenita: Electrophysiologic, Histopathologic, and Molecular Genetic Studies

A family with paramyotonia congenita (PC) is presented. At least 10 family members were affected in an autosomal dominant inheritance pattern. The proband had cold-sensitive muscle stiffness, paradoxical myotonia, and intermittent muscle weakness since childhood. The serum level of creatine kinase was mildly elevated and short exercise test with cooling revealed a drastic reduction of compound muscle action potentials with repetitive discharges. Muscle biopsy revealed marked variation in the fiber size and increased internal nuclei. The molecular biological study revealed a common missense mutation (Arg1448Cys) at the voltage-gated sodium channel gene (SCN4A). The repetitive CMAP discharges during short exercise test with cooling observed in the proband has not been reported previously. This observation needs to be confirmed among PC patients with different mutations. This is the first report on a PC family confirmed by the molecular biological technique in Korea.

Spectrum of inherited myotonias and periodic paralyses

To study the spectrum of inherited myotonias and periodic paralyses in Saudi Arabia. Forty nine patients with electromyography confirmed mytonotic disorders and periodic paralysis were seen at King Khalid University Hospital between January 1985 and January 1998. Data was analyzed and available patients reassessed in order to document fully the various clinical features and ascertain the diagnosis and mode of inheritance. There are 11 patients with Thomsen's disease; 21 patients with Becker's disease, most of them had an early onset of 2-3 years; 12 patients with myotonic dystrophy; and 5 Filipino patients with periodic paralyses, 3 of them with associated thyrotoxicosis. The spectrum of these disorders is similar to that described in western reports, apart from 2 main differences. First, is the clear predominance of Beckeri's disease [45%] which has a lower age of onset. This is probably the result of the high local consanguinity rate. Secondly is the absence of periodic paralysis in Saudis, while some patient had associated thyrotoxicosis, which is well recognized in Far East populations. These disorders are poorly studied in Saudi Arabia deserve further epidemiological and genetic assessment

A Case of Paramyotonia Congenita

Paramyotonia congenita (PMC), an autosomal dominant non-progressive muscle disorder, is characterised by cold-induced stiffness followed by muscle weakness. The weakness is considered to be caused by a dysfunction of the sodium channel in muscle fiber. We report a 37-year-old male patient with PMC, complaining of episodic myotonia and motor weakness on cold exposure. In this patient, we performed clinical and neurological examination, electrophysiologic examination and muscle biopsy. On electrophysiologic study, needle EMG showed spontaneous myotonic discharges at room temperature but disappeared after cooling. Amplitude of compound action potential in abductor pollicis brevis muscle decreased significantly after cooling the tested extremity. Muscle biopsy showed a minimal variation of muscle fiber diameters, internal nuclei, chained nuclei, occasional atrophic fibers in vastus lateralis muscle. His mother, his son, three of six siblings, and five of eleven nephewes are affected with same symptomes.

A Case of Adynamia Episodica Hereditaria

This is a case report of 32 year-old man with adynamia episodica hereditaria. Adynamia episodica hereditaria is a rare disorder characterized by episodic atacks of muscle weakness occuring in association with an increased serum concentration of potassium. The disorder is usually inherited as autosomal dominant trait and myotonia can be seen in much of the cases. And it is uncertain whether adynamia episodica hereditaria and paramyotonia congenita are variable manifestations of the same disease or not. We now reporta case of adynamia episodica hereditaria with myotonia with the special reference to pathophysiology of paralysis and myotonic symptom.

Myotonia Dystrophica: A Case Report / 대한정형외과학회잡지

Myotonia dystrophica(Synonym: Myotonia atrophica, Dystrophia myotonia, Steinert's disease) is a autosomal dominant hereditary multisystemic disorder involving several organs besides skeletal muscle, and commonly called with myotonia congenita, paramyotonia congenita as myotonia. Although most cases are of adult onset, where a mother has the disease, neonatal dystrophia myotonia can occur in her offspring. The main feature is a steadily progressive muscle dystrophy, complicated by myotonia, which is a failure of muscles to relax normally after a forceful contraction. Steinert in 1909 was the first to report the finding of atrophic testes and baldness in patients with myotonia dystrophica, and the other clinical feature of myotonia dystrophica were reported by many authors after that time. We are reporting a case of myotonia dystrophica, which showing familial history with brief review of literature.