Clinical Vignette A 55-year-old female with a recent history of interstitial lung disease reported weakness in her arms and legs. Recently she had noticed that she could not climb the 10 steps up from her basement. She had also developed…
In this chapter, we discuss a group of hereditary, often progressive, muscle disorders. These can be categorized as channelopathies, metabolic and mitochondrial myopathies, muscular dystrophies, and congenital myopathies ( Table 70.1 ). TABLE 70.1 Hereditary Myopathies Myopathy Type Locus Gene…
Lambert-Eaton Myasthenic Syndrome Clinical Vignette A 61-year-old woman with no remarkable past medical history developed, over a few months, weakness of her legs with difficulty getting in and out of chairs and climbing stairs. She also experienced significant fatigue. This…
Clinical Vignette A 65-year-old previously healthy man presented to the emergency department for several months of progressive upper extremity weakness and blurry vision. He reports that over the past 3 months, playing the violin and mowing the lawn have become…
Diagnostic Approach Clinical Vignette A 65-year-old man developed a tingling sensation in the toes, which quickly gave way to painful numbness. Over the next few months, paresthesias ascended to involve his distal thighs and fingertips. Within 6 months, he required…
Clinical Vignette A 13-year-old boy presents with frequent tripping. He enjoys playing baseball but has had several falls this season, one resulting in a fractured ankle. Born at term, his early developmental milestones were normal and he walked at 13…
Peripheral nerve hyperexcitability (PNH) syndromes present with involuntary, continuous muscle overactivity due to hyperexcitability of the motor axon. PNH syndromes are a heterogeneous group of disorders with distinct clinical and electrodiagnostic features. Muscle cramps are the hallmark of these conditions,…
Clinical Vignette A 48-year-old hospital administrator began having difficulties during meetings when her back would stiffen up every time she was asked to get up to speak. Subsequently, she developed episodes of anxiety accompanied by her left leg tightening up.…
Clinical Vignette A 35-year-old man sought medical attention for leg weakness. He noticed difficulty getting up from low chairs and ascending stairs. Looking back, he reported that 10 years previously he had noticed some difficulty when trying to stand after…
Clinical Vignette A 54-year-old man reported painless left arm weakness for 6 months. While exercising at the gym, he noticed difficulty lifting weights with his left arm. Progressively he had difficulty cutting food and opening jars with his left hand.…