Term
What dzs fit in categrory 1 - Proximal "limb-girdle" weakness?
|
|
Definition
Duchenne - hereditary
Polymyositis/Dermatomyositis - aquired |
|
|
Term
| dx: Heliotropic rash and dilated capillary loops in the nail beds. |
|
Definition
| Dz: Dermatomyosistis -- a humorally mediated micro-angiopathy. |
|
|
Term
| What is the pathology of polymyositis? |
|
Definition
| It is a cell mediated response againt mm fibers. |
|
|
Term
What dz fits pattern 2 (distal weakness)?
usually a neurapathy |
|
Definition
| Charcot - marie - tooth dz |
|
|
Term
Pattern 3 (proximal arm/distal leg weakness)
pt in his 20-30s
cant close eyes tightly, smile or wistle
biceps/tricepts atrophy
winging of scapula
hypertrophic extensor digitorum brevis in foot. |
|
Definition
| facioscapulohumeral dystrophy |
|
|
Term
Pattern 4 (distal arm/proximal leg weakness)
Assymetric
finger/wrist flexor weaker than shoulder abductors
more common in men |
|
Definition
|
|
Term
|
Definition
Oculopharyngeal
Myotonc dystrophy |
|
|
Term
Pattern 6 ( prominent neck extensor weakness)
Head drop syndrome |
|
Definition
Polymyositis
ALS
Myasthenia Gravis
:) |
|
|
Term
What does an elavted CK diagnose when it is:
10-100 times normal?
3-10 times normal? |
|
Definition
10-100: duchenne MD
3-10: motor nn dz, guillain barre, hypothyroidism, .. |
|
|
Term
| Should you use a muscle biopsy for hereditary mm disorders? |
|
Definition
No, there are blood test for hereditary disorders.
Use biopsy for aquired ones. |
|
|
Term
| Which mm should you biopsy? |
|
Definition
grade 4 or better
UE: biceps
LE: vastus lateralis
Do NOT biopsy Gastrocnemius bc of mixed in tendon and mostly type II fibers. |
|
|
Term
| What should you see in a normal mm biopsy? |
|
Definition
Uniform
Peripheral nuclie
Boring - no inclusions
Checkerboard -- type I and type II |
|
|
Term
| What would you see in a biopsy of dermatomyositis? |
|
Definition
|
|
Term
Dx:
variable fiber size
necrotic and regenerating fibers
endomysial inflamation
|
|
Definition
|
|
Term
| Where do you see amyloid plaques? |
|
Definition
|
|
Term
Dx:
on biopsy...
variable fiber sizes
regenerating and necrotic fibers
no staining using dystrophin antibodies |
|
Definition
|
|
Term
| In what mm dz do you see central nuclei? |
|
Definition
|
|
Term
| what is the safetly factor defined as? |
|
Definition
| it is the difference bw the endplate potential (EPP) and the current required to make the mm fire. |
|
|
Term
| What are the 3 sources of ATP in mm? |
|
Definition
Creatine phosphate
Oxidative phosphorylation
Substrate level // // |
|
|
Term
Dx: autoimmune dz,
Abd against ACh-R (80% of the time)
Weakness in levator palpebrae
Enhanced ptosis
Tensilon positive
|
|
Definition
|
|
Term
| What does Hering's law explain? |
|
Definition
| Worsening ptosis on one side when the eyelid is elevated. this is due to the equal innervation of LPS relaxing one side, has same effect on the other. |
|
|
Term
| What is injected during a tensilon (edrophonium) test? |
|
Definition
| competitive ACh esterese inhibitor. |
|
|
Term
| When do you see a positive anti-MuSK (receptor tyrosine kinase antibodies) |
|
Definition
| In pts with a thymoma, or older pts with MG. |
|
|
Term
| What does a single fiber EMG (jitter) rule out? |
|
Definition
| if there is no increased jitter, you can rule out neuromuscular transmission as a cause for weakness. |
|
|
Term
| List the differences bw ALS and MG. |
|
Definition
ALS involves upper and lower motor nn, weakness usually myotomal and assymetrical, pts lose wt, it is fatal. Cause is unknown.
MG involves generalized weakness, proximal mm symmetrical. Treatable autoimmune dz. |
|
|
Term
Dx: Autoimmune dz
Reduced Ach release
usually with small cell carcinoma of lung |
|
Definition
|
|
