Neuromusc Disease; Path Of Motor N, Pns Disease

Front 1

Calcium interacts with _____________, resulting in neurotransmitter vesicle fusion and release of vesicle contents into the NMJ.

Back 1

Synaptotagmin

Front 2

ACh interacts with post-synaptic (nicotinic, muscarinic) receptors on the post-synaptic muscle membrane resulting in depolarization of muscle cells.

Back 2

nicotinic

Front 3

Lambert-Eaton Myasthenic Syndrome: pathophys

Back 3

Pre-synaptic disease due to altered ACh release.

Antibodies are formed against presynaptic voltage-gated calcium channels in the neuromuscular junction.

Front 4

Lambert-Eaton Myasthenic Syndrome: symptoms

Back 4

Muscle weakness: proximal more than distal. Bulbar (facial)

ANS symptoms - dry mouth, constipation, impotence

Front 5

Lambert-Eaton Myasthenic Syndrome: associations

Back 5

Cancer, especially small cell lung cancer.

Front 6

Lambert-Eaton Myasthenic Syndrome: tx

Back 6

Treat underlying malignancy

Also IV prednisone, IV immunoglobulins

Front 7

Myasthenia gravis: pathophys

Back 7

Post-synaptic disease due to autoimmune attack at AChRs in NMJ.

Front 8

Myasthenia gravis: symptoms

Back 8

progressively reduced muscle strength with repeated use and recovery of muscle strength at rest.

Specific weakness more common than overall fatigue. ESPECIALLY extraocular weakness (905). Bulbar weakness is common. Usually both proximal, distal, and symmetric.

Front 9

Myasthenia gravis: onset

Back 9

Different for men and women. Mean onset for women is younger (28 vs 42).

Front 10

Myasthenia gravis: dx

Back 10

Anti-AChR receptor antibody test.

Front 11

Myasthenia gravis: treatment

Back 11

Aim is to diminish autoimmune process and includes prednisone, plasmapheresis, IV Ig, and other immunosuppressants.

Also aim at increasing availability of ACh.

THYMECTOMY esp if thymoma is present.

Front 12

Muscle disease unrelated to a disorder of innervation or NMJ

Back 12

myopathy

Front 13

Myopathy: sx

Back 13

Weakness - more PROXIMAL than DISTAL

Normal sensation

Decreased/absent deep tendon reflexes

Front 14

deep tendon reflexes: defn

Back 14

aka stretch reflexes. the ones tested for (biceps, patellar, etc)

Front 15

muscle diseases caused by muscle membrane protein abnormalities are _________

Back 15

muscular dystrophies

Front 16

mscular dystrophy related to dystrophin : method of inheritance

Back 16

X-linked recessive

Front 17

(Duchenne, Becker) muscular dystrophy is more severe. Why?

Back 17

Duchenne. This is because dystrophin is ABSENT instead of mutated (Becker)

Front 18

Duchenne muscular dystrophy: early symptoms

Back 18

Delayed walking, can't run or jump, rubbery feeling muscles. Age 2-3

Front 19

Duchenne muscular dystrophy: later symptoms

Back 19

Calf muscle hypertrophy, toe walking

Walking slows age 5-6

Patient will have difficulty climbing steps age 7-9

Unable to rise from floor without help and UE weakness more apparent age 10-12

nonambulatory age 12-14

Front 20

Usual cause of death of Duchenne muscular dystrophy

Back 20

Cardiac disease, usually dilated cardiomyopathy

Pulmonary disease, ventilator dept (late teens, early 20s)

Front 21

Gowers' sign: defn

Back 21

Gowers' sign is a medical sign that indicates weakness of the proximal muscles, namely those of the lower limb. The sign describes a patient that has to use his hands and arms to "walk" up his own body from a squatting position due to lack of hip and thigh muscle strength. Classic in DMD.

Front 22

Duchenne muscular dystrophy: treatment

Back 22

Prednisone - slows progression

Cardiac mgmt - afterload reducers

Ventilator

PT and orthotics - contracture prevention

Orthopedic sx for scoliosis

Front 23

Becker muscular dystrophy: age of onset and course of disease

Back 23

later, may not present until teens.

Progresses more slowly. CARDIOMYOPATHY MORE PROMINENT.

Front 24

Limb girdle muscular dystrophy: defn

Back 24

only a descriptive term for muscular dystrophies OTHER than DMD and BMD. Large number of rare disorders.

Weakness and wasting restricted to limb musculature (proximal > distal)

Front 25

Lab test abnormalities in muscular dystrophies

Back 25

ELEVATION OF CPK (serum creatine kinase)

Muscle biopsy - dystrophic changes

Front 26

Nemaline myopathy: DEFN

Back 26

congenital, hereditary neuromuscular disorder that causes muscle weakness, generally nonprogressive, of varying severity.

Most severe weakness in face, neck flexors, and proximal limb muscles.

Depressed or absent DTRs.

Front 27

Nemaline myopathy: pathophys

Back 27

Mutations in genes encoding components of sarcomeric thin filaments

Front 28

Nemaline myopathy: presentation

Back 28

Neonatal or 1st year of life

Hypotonia, weakness, feeding probs

Slowly progressive or statis

Respiratory difficulties may be insidious - nocturnal hypoventilation

Most can walk.


(some are more severe)

Front 29

biopsy of muscle from a person with nemaline myopathy shows what?

Back 29

bnormal thread-like rods, called nemaline bodies, in the muscle cells

Front 30

Central core disease: defn and symptoms

Back 30

Autosomal dominant congenital myopathy.

Mild to severe proximal muscle weakness with variable involvement of facial and neck muscles.

Extraocular muscles often spared.

Front 31

Central core disease: related disorders

Back 31

Susceptibility to malignant hyperthermia

Multiminicore disease

Front 32

Centronuclear myopathy: defn

Back 32

AKA myotubular myopathy

group of congenital myopathies where cell nuclei are abnormally located in skeletal muscle cells. In CNM the nuclei are located at a position in the center of the cell, instead of their normal location at the periphery.

Front 33

Centronuclear myopathy: symptoms

Back 33

severe hypotonia, hypoxia-requiring breathing assistance, and scaphocephaly

Front 34

Myotonic dystrophy (DM1) defn

Back 34

chronic, slowly progressing, highly variable, inherited multisystemic disease. It is characterized by wasting of the muscles (muscular dystrophy), cataracts, heart conduction defects, endocrine changes, and myotonia.

Front 35

Myotonic dystrophy (DM1) : 3 phenotypes

Back 35

1) Mild
2) Classic
3) Congenital (most severe)

Front 36

Myotonic dystrophy (DM1) : Mild form

Back 36

Cataracts and mild myotonia

Front 37

Myotonic dystrophy (DM1) : classic form symptoms

Back 37

Predominant symptom: Distal Muscle weakness/wasting (leads to gait problems and problems with fine motor.)

Myotonia

Cataracts

Cardiac conduction abnormalities

Front 38

Myotonic dystrophy (DM1) : congenital form

Back 38

Hypotonia

Severe generalized weakness at birth, with respiratory insufficiency and early death

Mental retardation

Front 39

Myotonic dystrophy (DM1) : Pathophys

Back 39

Trinucleotide repeat in DMPK (myotonic dystrophy protein kinase) gene (autosomal dominant)

Front 40

most common inflammatory myopathy in all age groups

Back 40

dermatomyositis

Front 41

T/F Children and adults can have both dermatomyositis and polymyositis

Back 41

F. Children rarely have polymyositis.

Front 42

dermatomyositis and polymyositis: presentation of motor issues

Back 42

Varying degrees of muscle weakness, usually developing slowly.

Mostly proximal, becomes distal later in disease.

NEVER has involvement of extraocular muscles.

Sensation remains normal

Front 43

Dermatomyositis: skin manifestations

Back 43

Heliotrope rash

Gottron's papules at knuckles

Dilated capillary loops at base of nails with distorted cuticles

Front 44

What are other associations with dermatomyositis?

Back 44

CANCERS

Front 45

dermatomyositis and polymyositis: dx

Back 45

Serum muscle enzyme concentrations

Muscle biopsy

EMG

Front 46

dermatomyositis and polymyositis: treatment

Back 46

prednisone - 1st line

immunosuppressants - when steroids stop working

Front 47

Pathology of Amyotrophic lateral sclerosis

Back 47

form of motor neurone disease caused by the degeneration of upper and lower neurons, located in the ventral horn of the spinal cord and the cortical neurons that provide their efferent input.

Front 48

Clarke's column: defn

Back 48

group of interneurons found in the medial part of Lamina VII, also known as the intermediate zone, of the spinal cord. It is mainly located from the C8 to L2-L3 levels and is an important structure for <b>proprioception.</b>

Spared in ALS.

Front 49

Some familial ALS show mutations in genes that encodes for ____________

Back 49

Copper/Zinc Superoxide Dismutase (SOD-1)

Front 50

Superoxide Dismutase : function

Back 50

catalyze the dismutation of superoxide into oxygen and hydrogen peroxide --> free radical neutralization. Protects from free radical damage.

Front 51

Spinal muscular atrophy: defn

Back 51

Degeneration of lower motor neurons in brain stem and spinal cord with atrophy of motor nerve roots and skeletal muscles.

Front 52

Spinal muscular atrophy: etiology

Back 52

autosomal recessive

Front 53

Werdnig-Hoffman Disease - defn

Back 53

most severe form of spinal muscular atrophy, affecting infants

Front 54

Degenerative changes in Neurons in ALS

Back 54

accumulation of neurofilaments: associated with reduction of branched structures of the postsynaptic apparatus and defect of axonal sprouting - indication of "dying back" etiology of motor neuron disease (?)

See excessive lipofuscin pigment

Front 55

Difference between ALS and SMA

Back 55

ALS affects upper and lower motor neurons, SMA only lower (no cortical)

Front 56

Acute inflammatory demyelinating neuropathy is AKA

Back 56

Guillain Barre Syndrome

Front 57

Charcot-Marie-Tooth Disease
: defn

Back 57

most common form of hereditary neuropathy. Myelin predom involved.

Repeated demyelination and remyelination - "onion bulb" formation leading to enlargement of affected nerves that can be palpated (hypertrophic neuropathy)

Front 58

Deficiency of vitamin _____ associated with neuropathy

Back 58

thiamine

Front 59

Pathologic changes in acquired metabolic and toxic neuropathies (eg, thiamine deficiency, diabetes, etc)

Back 59

Non-specific

Degeneration of axons and myelins with loss of nerve fibers.