Term
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Definition
| dysfunction of teh schwann cell or damage to the myelin sheath. Nodes grow back shorter (onion bulb) |
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Term
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Definition
| Result of primary destruction of the axon. |
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Term
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Definition
| degeneration of the distal portion of a fiber after transection |
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Term
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Definition
| breakdown of myosin and actin with a decrease in cell size after denervation. triangular (angulated) cell shape. Causes round zone of disorganized myofibers (target fiber) |
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Term
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Definition
| thinly myelinated small-caliber axons after regeneration |
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Term
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Definition
| Slow twitch, red, myoglobin, darker at 4.2 pH with stain, oxidative enzymes |
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Term
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Definition
| glycolytic enzymes, fast, stains darkly at 9.2 pH |
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Term
| Type II muscle fiber atrophy |
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Definition
| Associated with disuse. Also glucocorticoids. |
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Term
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Definition
| destruction of a portion of the length, follow by myophagocytosis and extensive collagen and fat deposition |
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Term
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Definition
| Satellite precursor cells. Large internalized nuclei and prominent nucleoli. Basophilic cytoplasm. |
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Term
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Definition
| Acute Inflammatory Demyelinating Polyradiculoneuropathy. PNS. Starts distally, ascends. demyelination of spinal nerve roots. Radiculoneuropathy. influenza-like illness. Perivenular/endoneurial infiltration @ motor roots |
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Term
| Chronic Inflammatory Demyelinating Polyradiculoneuropathy |
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Definition
| subacute or chronic course of guillain-Barre. Mixed and symmetric. |
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Term
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Definition
| Peripheral nerves. Mycobacterium leprae. endoneurial fibrosis and multilayered thickening. Involves nociceptors. Tuberculoid from active cell-mediated immune response. |
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Term
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Definition
| loss of proprioception and vibratory sensation |
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Term
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Definition
| following chicken-pox, persists in sensory ganglia. reactivation causes shingles (decreased cell-mediated immunity). |
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Term
| Hereditary Motor and Sensory Neuropathy Type I |
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Definition
| HMSN I : Charcot-Marie-Tooth, demyelinating type. peroneal muscular atrophy, leg below the knee. pes cavus. Genes: 17p11.2 duplication/PMP22, MPZ, connexin-32, LITAF, EGR2. Hypertrophic Neuropathy. |
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Term
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Definition
| axonal form: similar to type I. Genes: KIF1B. Loss of myelinated axos in the predominant finding. Segmental demyelination is infrequent |
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Term
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Definition
| Dejerine-Sottas Neuropathy. Dominant, starts in childhood. enlarged peripheral nerves, reduced conduction velocity, both trunk and limb. Genes: PNP22, MPZ PRX (periaxin), EGR2 |
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Term
|
Definition
| distal symmetric neuropathy, autonomic neuropathy, focal or multifocal asymmetric neuropathy. Likely polyol or nonenzymatic glycation. relative loss of small fibers |
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Term
|
Definition
| distal, symmetric, muscle cramps, distal dysesthesias, axonal degeneration |
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Term
|
Definition
| axonal neuropathy, neuropathic beriberi |
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Term
| pseudoneuroma / amputation neuroma |
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Definition
| tangled axonal processes as axons continue to grow and regenerate |
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Term
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Definition
| Infantile Motor Neuron Disease. progressive illness that destroy anterior horn cells. Genes: SMN1/2. More retained copies of SMN2 are better. entire fascicle is atrophic |
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Term
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Definition
| Most common SMA (type I) first 4 months of life, 'floppiness'. Death at about 3. |
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Term
|
Definition
| progressive weakness and wasting of muscle replaced by fibrofatty tissue and collagen. |
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Term
| X-Linked Muscular Dystrophy |
|
Definition
| Duchenne/Becker Dystrophy. DMD is more severe. dilated cardiomyopathy. Gene Xp21 region for dystrophin. Variation in fiber size, more internalized nuclei, necrosis, regeneration, endomysial connective tissue proliferation. Cognitive impairment, creatine kinase elevated |
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Term
| limb girdle muscular dystrophies |
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Definition
| preferentially affect the trunk and limbs. Type I: dominant, Type II: recessive. genes: sarcoglycan complex of proteins like beta-dystroglycan |
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Term
|
Definition
| sustained involuntary contraction. dominant, CTG repeat, anticipation. Ring fiber with subsarcolemmal band of cytoplasm often associated with irregular sarcoplasmic mass. Cataracts, balding, gonadal atrophy, cardiomyopathy |
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Term
| Hyperkalemic periodic paralysis |
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Definition
|
|
Term
| Hypokalemic periodic paralysis |
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Definition
| Gene: voltage-gated L-type calcium channel |
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Term
|
Definition
| Malignant hyperthermia: hypermetabolic state triggered by anesthetics like halogenated agents or succinylcholine. Gene: RyR1 for rynodine receptor. Uncontrolled cacium efflux from the sarcoplasm. Tetany |
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Term
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Definition
| severe joint contractures |
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Term
|
Definition
| Carnitine transport or deficiencies of the mitochondrial dehydrogenase enzyme. muscle pain, tightness and myoglobinuria |
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Term
|
Definition
| Oxidative Phosphorylation Diseases: both nuclear and mitochondrial genes. weakness, neurologic symptoms, lactic acidosis, cardiomyopathy, mitochondrial aggregates, ragged red fibers, paracrystalline parking lot inclusions. |
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Term
|
Definition
| Mitochondrial Myopathy: subacute necrotizing encephalopathy. |
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Term
| X-linked cardioskeletal myopathy |
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Definition
| Barth Syndrom, a Mitochondrial Myopathy: due to mutation in nuclear DNA |
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Term
| Nuclear DNA Mitochondrial Myopathies |
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Definition
| Leigh syndrome, exertional myoglobinuria, infantile x-linked cardioskeletal myopathy (Barth) |
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Term
| point mutations in mtDNA Mitochondrial Myopathies |
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Definition
| myoclonic epilepsy with ragged red fibers, leber hereditary optic neuropathy, mitochondrial encephalomyopathy |
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Term
| Deletions/Duplications in mtDNA Mitochondrial Myopathies |
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Definition
| chronic progressive external ophthalmoplecia (weakness of extraoccular motion), Kearns-Sayre syndrome (pigmentary degeneration of retina and heart block) |
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Term
|
Definition
| skin and skeletal muscle. lilar or heliotrope discoloration of upper eyelids and periorbital edema. Grotton lesions. proximal muscles first. dysphagia, visceral cancers. capillaries targeted. perifascicular atrophy |
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Term
|
Definition
| scaling erythematous eruption or dusky red patches over the knuckles, elbows and knees |
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Term
|
Definition
| symmetric proximal muscle involvement like dermatomyositis but lacks cutaneous involvement. CTLs and antinuclear antibodies. inflammatory cells in endomysium |
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Term
|
Definition
| involvement of distal muscles, asymmetric, over age 50, extensors of the knee and flexors of the wrists/fingers. beta-amyloid/tau protein and CD8 cytotoxic T cells. Rimmed vacuoles. Basophilic granules. amyloid deposits staining with Congo red |
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Term
|
Definition
| proximal muscle weakness, fiber atrophy, increased number of internal nuclei, glycogen aggregates, mucopolysaccharide deposition, interstitial lymphocytosis |
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Term
|
Definition
| rhabdomyolysis with accompanying myoglobinuria, potential renal failure. swelling of cells, denervation |
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Term
|
Definition
| vacuoles within myocytes including autophagic vacuoles and curvilinear bodies, mostly type I fibers |
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Term
|
Definition
|
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Term
|
Definition
| thymic hyperplasia. acetylcholine receptor targeting antibodies. fixes complement to targets, destroys or blocks receptors. weakness, ptosis, diplopia |
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|
Term
| Lambert-Eaton Myasthenic Syndrome |
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Definition
| Like Myasthenia Gravis but paraneoplastic with proximal muscle weakness, improved transmission with repetition, fewer vesicles, no AChEI effect. |
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