... more recently developed tools (EVE and REVEL) with detailed cell-based electrophysiology, for 126 CLCN1 variants discovered in patients with the skeletal muscle channelopathy myotonia congenita. We found poor accuracy for most tools. The highest accuracy was obtained with MutationTaster (84.58...

... of the clinical significance and inheritance pattern of variants can be challenging. We report our approach to evaluating variants in the skeletal muscle chloride channel ClC-1 identified in 223 probands with myotonia congenita as an example of these challenges. Sequencing of CLCN1, the gene that encodes...

... = 24, LGMD = 144, DM1&2 = 44). Among IMNM patients 51% (61/119) were females. Electrical myotonia was observed in 56% of IMNM patients (67/119), affecting 22% (221/995) of muscles examined. When electrical myotonia was present amongst IMNM patients, the median rate identified in muscles examined...

... Lamotrigine blocks the Na_v1.4 isoform of voltage-gated sodium channels in skeletal muscle. In a randomised, controlled, crossover study, Andersen et al. show that lamotrigine improves patient-related and objective outcomes in non-dystrophic myotonia compared with placebo. Inexpensive...

... of the inferior alveolar canal and periosteal new bone formation in the midshaft of the proximal phalanges are described in a patient with this disease. Myotonia atrophica Dystrophia myotonica Mytonic dystrophy: Review of the literature and new radiographic findings L J SKOCZYLAS·, R P LANGLAIS·, and R S YOUNG...

.... Corrochano Sanchez et al. identify a novel mutation (I588V) in SCN4A, which encodes the Nav1.4 voltage-gated sodium channel, in a patient with myotonia and periodic paralysis. By generating and characterizing a mouse model (‘draggen’) carrying the equivalent point mutation (I582V...

... in Appendix 1 23 1 2013 4 4 2013 9 4 2013 © The Author (2013). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: [email protected] 2013 Abstract Non-dystrophic myotonias are rare diseases caused by mutations...

... (BNSU), we identified an initial cohort of 22 families from the UK with a strong clinical suspicion of MC. Inclusion criteria included a history of muscle stiffness, myotonia with ‘warm-up’ on examination and EMG detectable myotonia. Individuals were excluded if they presented with profoundly cold...

... the stiffness further, but resulted in weakness and increased myotonia on EMG. The EMG features of this patient showed prominent bursts of repetitive discharges at room temperature, but decreased repetitive discharges upon cooling of the muscle, while the myotonic discharges became prominent only upon cooling...

...G. Drost; J. H. Blok; D. F. Stegeman; J. P. van Dijk; B. G. M. van Engelen; M. J. Zwarts Autosomal recessive generalized myotonia is a non-dystrophic disorder of skeletal muscles. This disease was separated from the autosomal dominant myotonia congenita (Thomsen's disease) by Becker (1977...

... by at least seven different mutations in the CLCNI (ClC-1) skeletal muscle chloride channel gene on chromosome 7q35. Hyperkalaemic periodic paralysis, paramyotonia congenita and a small heterogeneous group of related pure myotonias are autosomal dominant disorders and are due to at least 16 different...

...F. LEHMANN-HORN; P. A. IAIZZO Present Address: Department of Anesthesioogy, University of Minnesota, Minneapolis, Mn, U.S.A. Correspondence to F.L.-H. 23 4 1990 © 1990 British Journal of Anaesthesia 1990 Abstract Excised muscles from patients with myotonia or periodic paralysis were subjected...

... of laryngeal competence (in- creasing the risk of aspiration); and loss of KEY WORDS pharyngeal tone (increasing the risk of obstructive Anaesthetics i. v : propofol Myotonia dystrophies. apnoea). The myocardium may be affected...

... with myotonia demonstrated an increase in peak torque during the fatigability test; this response was unique among the diagnoses we tested. Isokinetic testing may provide, in some patients with neuromuscular disease, valuable information when used in conjunction with MMT for sequential monitoring of strength...

..., difficulty with facial or bulbar muscles, and episodes of dark urine. Medical and family history was negative. Cramps and contractures may be identical clinically. The former is more common in neurogenic disease, whereas in myopathies they are more likely to be contractures or myotonia. True...

... subtypes will be identified, and these will be designated DM3, etc. This nomenclature was recommended by an international panel (Ashizawa 2000) and is followed in this chapter. Alternatively, some experts reserve the term ‘myotonic dystrophy’ (myotonia atrophica, dystrophia myotonica, myotonic muscular...

...0 18 06 2009 Muscle symptoms in myotonic dystrophy are very variable. The diagnosis is often delayed or missed because myotonic dystrophy is not being considered as a possibility. Muscle stiffness (myotonia) is important for the diagnosis, but much less important than weakness for patients...

..., and ophthalmological disorders. Executive dysfunction can lead to missed appointments and an apathetic attitude, causing patients to underestimate symptoms. The findings of both clinical and electrical myotonia should suggest myotonia congenita, DM1, or DM2. Myotonic dystrophy demonstrates anticipation, where...

...Oxford University Press The chapter begins with a general description of the clinical findings in conditions where hyperexcitability occurs. These are divided into the dystrophic conditions, such as myotonia dystrophy, and the non-dystrophic conditions, which include myotonia congenita...

...Oxford University Press Myotonia congenita (MG) and various ion channel myotonias all fall under the umbrella of nondystrophic myotonias (NDMs) and are distinct from myotonic dystrophy because they are caused by dysfunction of key skeletal muscle ion channels alone without any other systemic...