The spectrum of RYR1 mutation associated disease encompasses congenital myopathies, exercise induced rhabdomyolysis, malignant hyperthermia susceptibility and King-Denborough syndrome. We report the clinical phenotype of two siblings who presented in infancy with hypotonia and striking fatigable ptosis. Their response to pyridostigimine was striking, but genetic screening for congenital myasthenic syndromes was negative, prompting further evaluation. Muscle MRI was abnormal with a selective pattern of involvement evocative of RYR1-related myopathy. This directed sequencing of the RYR1 gene, which revealed two heterozygous c.6721C>T (p.Arg2241X) nonsense mutations and novel c.8888T>C (p.Leu2963Pro) mutations in both siblings. These cases broaden the RYR1-related disease spectrum to include a myasthenic-like phenotype, including partial response to pyridostigimine. RYR1-related myopathy should be considered in the presence of fatigable weakness especially if muscle imaging demonstrates structural abnormalities. Single fibre electromyography can also be helpful in cases like this.
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http://dx.doi.org/10.1016/j.nmd.2014.05.003 | DOI Listing |
Front Neurol
December 2024
Department of Internal Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
Background: Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune disorder of the presynaptic neuromuscular junction associated with antibody mediated dysfunction of voltage-gated calcium channels (VGCCs). LEMS can exist as a paraneoplastic syndrome, paraneoplastic-LEMS (P-LEMS), when associated with tumors, most commonly, small cell lung carcinoma (SCLC) or as a non-paraneoplastic condition (NP-LEMS) when no malignancies are detected.
Methods: A retrospective chart review was conducted in 3 tertiary hospitals in Saudi Arabia for patients diagnosed with LEMS between January 2010 and January 2020.
Yale J Biol Med
December 2024
Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, Texas, USA.
Patients with prior SARS-CoV-2 infections can develop chronic symptoms; this clinical presentation has been called post-acute sequelae of SARS-CoV-2 infection, post-COVID condition, and long COVID. It can develop in both outpatient cases and in hospital cases; the frequency depends on the severity of infection and comorbidity. Many of these patients have exercise limitation when tested using cardiopulmonary exercise tests.
View Article and Find Full Text PDFCureus
November 2024
Surgery, Johns Hopkins University School of Medicine, Baltimore, USA.
Radiol Case Rep
January 2025
Department of Radiodiagnosis, Jawaharlal Nehru Medical College, Datta Meghe Institute of Higher Education and Research, Sawangi (Meghe), Wardha, Maharashtra, India 442001.
Myasthenia gravis is an acquired neuromuscular disorder characterized by weakness of the extra-ocular muscles, which progresses to generalized weakness of the voluntary muscles and fatigability. The presented case is of a 70-year-old male patient who presented with complaints of drooping of bilateral eyelids and breathlessness and was diagnosed to have myasthenia gravis and thymic mass. It is uncommon for an elderly patient to present with thymic mass and myasthenia gravis concurrently.
View Article and Find Full Text PDFNeuromuscul Disord
October 2024
Neuromuscular Research Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Neurology, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran. Electronic address:
Variants in the CHRNE gene can lead to a condition called congenital myasthenic syndrome (CMS), which affects the neuromuscular junction (NMJ). CHRNE mutations are the most common cause of CMS. Seventy-seven patients with a possible diagnosis of CMS were referred to the neuromuscular clinic of Shariati Hospital affiliated with the Tehran University of Medical Sciences.
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