Muscle Disorders Flashcards

Question

Emery-Deifuss Muscular Dystrophy (EDMD)

Answer 1

Hereditary myopathy

Answer 2

Contractures of elbows, posterior neck and ankles Muscle weakness and wasting Cardiac dz (arrhythmia and CM)

Answer 3

3rd MC MD | Slow progression of weakness, mainly facial and shoulder girdle muscles followed by leg, thigh and hip girdle weakness

Answer 4

Autosomal dominant | Reduction in D4Z4 repeats on 4q35

Answer 5

NMJ w/ defect in proteins required for neuromuscular tansmission or auto-Ab to the nicotinic Ach rec at the NMJ

Answer 6

``` Weakness that improves with rest Ptosis Diplopia Dysphagia Dysphonia Resp involvement Proximal muscle weakness No sensory, bowel or bladder inolvement ```

Answer 7

Exacerbation of sx to require ventilator support | Triggered by fever, infection, medications or stress

Answer 8

``` Aminoglycosids Macrolides Beta blockers ACE-I Quinidine Lidocaine Procainamide CNS dugs ( phenytoin) Antirheumatics-chloroquine D-Penacillamine Prednisone ```

Answer 9

``` AchE inhibitors Immunosuppression (steroids, azathioprine, cyclosporine, cyclophosphamide) Plasma exchange IVIG Thymectomy (some cases) ```

Answer 10

Enterovirus RNA virus PV1 MC, also PV2 and PV3

Answer 11

Sabin and Salk vaccines contain Ag from all 3 polio viruses | Salk is dead virus, only one used in US

Answer 12

Fecal oral | Peak in summer and fall

Answer 13

Virus enters GI tract and lymphatic cells Viremia w/ flu like sx Spreads to neurons w/ invasion to anterior horn cells Death of AHC leaves skeletal muscle w/o trophic factors to maintain muscle

Answer 14

``` Asymmetric paralysis of muscles Preservation of sensation Muscle pain Loss of reflexes Constipation/difficulty voiding ```

Answer 15

Loss of axons Preservation of sensory conductions Positive sharp waves and fibrillations Late EDX: large amp motor units d/t reninnervation

Answer 16

Group of neurodegenerative d/o characterized by progressive symmetric weakness and atrophy d/t loss of anterior horn cells of the SC and motor cranial nerve nuclei V, VII, IX, X, XI and XII

Answer 17

Autosomal recessive on Chr 5q SMN (survival motor neuron) gene

Answer 18

Age of onset and disease severity

Answer 19

SMA I: acute infantile, Werdnig-Hoffman SMA II: chronic infantile, intermediate SMA III: chronic juvenile, Kugelberg-Welander SMA IV: adult onset

Answer 20

Onset birth to 6 mo Never sits independently Death usually prior to 2 yo, later in some cases esp w/ technology

Answer 21

Onset 6-18 mo Will sit but never walk Death MC in 20-30's

Answer 22

Onset >18 yo Walks independently May have normal lifespan

Answer 23

Onset mid-30's Slowly progressive weakness Transitioning to WC dependence over 20 years Normal life expectancy

Answer 24

Mild facial weakness w/ sparing of extraocular muscles Tongue fasciculation's and/or poor suck Frog-leg positioning w/ abd breathing Scoliosis SMA II> III Joint contractures Wide-based Trendelenburg gait if ambulatory Sensation intact Fine tremor in hands Dec muscle tone and bulk, proximal>distal Reduced or absent reflexes Normal to above normal intelligence

Answer 25

Serum CK normal to 2 x normal

Answer 26

``` Spontaneous potentials Fasciculations in SMA II and III Large amp Long duration Polyphasic motor unit action potentials (MUAP) ```

Answer 27

Severe metabolic acidosis may occur during illness or fasting Resolves w/ IVF in 2-4 days

Answer 28

Congenital constriction of cerebral arteries, esp internal carotid artery, w/ collateral circulation that appears like a "puff of smoke" on ateriography

Answer 29

Proximally to distally

Answer 30

Neck deformity w/ shortening of SCM muscles resulting in limited neck rotation and lateral flexion.

Answer 31

Head tilt | Rotation

Answer 32

Associated GERD and torticollis