myasthenic syndrome

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Lam·bert-Ea·ton myasthenic syn·drome (LEMS),

(lam'bert ē'tŏn),
a generalized disorder of neuromuscular transmission caused by a defect in the release of acetylcholine quanta from the presynaptic nerve terminals; often associated with small cell carcinoma of the lung, particularly in elderly men with a long history of cigarette smoking. In contrast to myasthenia gravis, weakness tends to affect solely axial muscles, girdle muscles, and less often the limb muscles; autonomic disturbances, for example, dry mouth and impotence, are common; the deep tendon reflexes are unelicitable; on motor conduction studies, responses on initial stimulation are quite low in amplitude, but they show marked posttetanic facilitation after a few seconds of exercise. Lambert-Eaton syndrome is due to loss of voltage-sensitive calcium channels located on the presynaptic motor nerve terminal. See: myasthenic syndrome.
Farlex Partner Medical Dictionary © Farlex 2012

myasthenic syndrome

Lambert-Eaton syndrome, see there.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

my·as·then·ic syn·drome

(mī-as-then'ik sin'drōm)
A disorder of neuromuscular transmission marked primarily by limb and girdle weakness, absent deep tendon reflexes, dry mouth, and impotence; due to an immunologic disorder; often, especially in males, a paraneoplastic syndrome linked to small cell carcinoma of the lung.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012
References in periodicals archive ?
The Lambert-Eaton myasthenic syndrome 1988-2008: a clinical picture in 97 patients.
Diagnosis and treatment of Lambert-Eaton myasthenic syndrome. Neurol Clin 1994;12:387-99.
BioMarin has produced a medicine similar to the one the two boys - who suffer from Congenital Myasthenic Syndrome - have taken for up to 10 years.
Kerry Webster, whose sons James and Adam have the rare muscle disease congenital myasthenic syndrome, have been taking the drug 3,4DAP for the past 10 years.
The exception to this is the slow-channel congenital myasthenic syndrome (SCS) because it increases the synaptic response to acetylcholine neurotransmitter.
It is important to distinguish myasthenia gravis, present in this patient, from myasthenic syndrome (Eaton-Lambert syndrome, LEMS).
Their child was born with congenital myasthenic syndrome, a rare condition making his muscles too weak for him to breathe unaided.
The child, who cannot be identified, was born with congenital myasthenic syndrome (CMS), a rare neuromuscular condition.
Contributions cover acute neuropathies, chronic inflammatory demyelinating neuropathy and its variants, nonsystemic vasculitic neuropathy, dysimmune neuropathy, autoimmune autonomic ganglionopathy, myasthenia gravis with anti-acetylcholine receptor antibodies, muscle-specific receptor tyrosine kinase antibody-positive and seronegative myasthenia gravis, Lambert-Eaton myasthenic syndrome, idiopathic inflammatory myopathies, and stiff person syndrome.
The patient in whom this mutation was traced is a 20-year-old woman diagnosed with congenital myasthenic syndrome. Myasthenia gravis, which literally means grave muscle weakness, affects about 37,000 Americans.
Diseases of the Neuromuscular Junctions Conditions such as myasthenia gravis and congenital myasthenic syndrome (which is detectable at birth) cause problems with eye movement, facial expression, chewing, swallowing, respiration and, occasionally, arm and leg movement.
Some of the disorders affect skeletal muscle or the neuromuscular junction, such as hypokalemic periodic paralysis (HypoKPP) and LambertEaton myasthenic syndrome (LEMS).