030915 sk musc pathology

Question 1

what indicates muscle regeneration

Answer 1

enlarged nuclei and blue cytoplasm

Question 2

denervation atrophy appears as

Answer 2

clusters of fibers (of one type) become smaller and develop angular contours-group atrophy

Question 3

neurogenic atrophy

Answer 3

bimodal size distribution
angulated fibers
apparent increase in nuclei (nuclear clumps)
no necrosis, regeneration, fibrosis, or inflammation

Question 4

myopathic atrophy

Answer 4

random size variation
round fibers
centralization of nuclei
may have necrosis, regeneration, fibrosis, inflam

Question 5

ALS vs SMA

Answer 5

spinal muscular atrophy affects just lower motor neurons

Question 6

spinal muscular atrophy

Answer 6

degenerative LMN disorder of childhood more so than adulthood

proximal weakness is much more than distal

Question 7

types of muscular dystrophies

Answer 7

X linked: Duchenne, Becker

autosomal: myotonic

Question 8

Duchenne muscular dystrophy

Answer 8

99% have no or nearly no dystrophin

Question 9

Becker muscular dystrophy

Answer 9

85% have abnormal dystrophin in reduced quantity

Question 10

distal muscle weakness is characteristic of

Answer 10

neuropathy

Question 11

proximal muscle weakness is more common in

Answer 11

dystrophies

Question 12

CK for DMD

Answer 12

over 10,000

Question 13

Becker muscular dystrophy

Answer 13

adult population
later onset
near normal lifespan

Question 14

myotonic dystrophy

Answer 14

most common muscular dystrophy IN ADULTS

DM1 (CTG repeat expansion in DMPK gene)
autosomal dominant

DIFFICULTY RELEASING GRIP

weakness: DISTAL HANDS AND FEET (grip and foot drop), proximal muscles, elongated face

temporal wasting

Question 15

metabolic myopathies

Answer 15

mitochondrial myopathies

glycogen storage diseases

Question 16

MELAS

Answer 16

mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes

Question 17

MELAS-clinical

Answer 17

3 primary criteria:

• stroke-like episodes under 40, -encephalopathy
• lactic acidosis, ragged red fibers, or both (myopathy-proximal, eyes)

Question 18

clinical syndrome for myopathic form of glycogen storage dis

Answer 18

exercise intolerance w cramps and intermittent myoglobinuria

Question 19

inflammatory myopathies-types?

Answer 19

inclusion body myositis
dermatomyositis
polymyositis

Question 20

polymyositis

Answer 20

symmetric proximal muscle weakness
no rash
not associated w malignancy

Question 21

dermatomyositis-signs

Answer 21

Shawl sign
heliotrope rash around eyes
nail bed w hemorrhages
Gottron's papules
subcu calcifications

Question 22

pathology of dermatomyositis

Answer 22

microvasculature is attacked by antibodies and complement (ischemic atrophy and necrosis of fibers–PERIFASCICULAR ATROPHY)

Question 23

inclusion body myositis pathology

Answer 23

amyloid deposits
cytoplasmic inclusions of tuberofilaments
rimmed vacuoles

Question 24

toxic myopathies-types?

Answer 24

steroids

statins

Question 25

two types of axonal degeneration in peripheral nerve

Answer 25

neuronopathy or axonopathy | Wallerian degenration

Question 26

peripheral neuropathy-causes?

Answer 26

inflam hereditary (Charcot Marie Tooth) metabolic and toxic neuropathies traumatic neuropathies

Question 27

infectious neuropathies

Answer 27

leprosy | VZV

Question 28

onion bulb formation

Answer 28

Charcto Marie Tooth