OTHERS

Question 1

McCardle syndrome (skeletal muscle only)

glycogen accumulations
S/S:
painful cramps w/ exercise
myoglobunuria
muscular exercise fails to raise serum lactate levels

Answer 1

glycogen storage disease

Question 2

accumulation of lipid within myocytes

carnitine deficiency

Answer 2

lipid myopathies

Question 3

1/5 of proteins involved in oxidative phosphorylation encoded on mtDNA
-maternal inheritance pattern

ragged red fibers

three classes, 1-3

Answer 3

mitochondrial myopathies

Question 4

cushing’s syndrome with proximal weakness, muscle fiber atrophy, predominantly affecting type II fibers

chloroquine myopathy- vacuoles within myocytes

Answer 4

drug induced myopathy

Question 5

hyperthyroidism, hypothyroidism; acute or proximal muscle weakness which may precede onset of other signs of thyroid dysfunction

hypothyroidism can also cause muscular changes with fiber atrophy, cramping or aching of muscles, loss of DTRs

Answer 5

thyrotoxic myopathy

Question 6

produces toxic syndrome of rhabdomyolysis with myoglobinuria

leads to renal failure

can be generalized or localized to a single muscle group

Answer 6

ethanol “binge” drinking

Question 7

autoimmune disease caused by immune mediated loss of ACh receptors and having characteristics temporal and anatomic patterns as well as drug response

decreased numbers of ACh receptors, circulating antibodies to AChRs

thymic hyperplasia
thymoma

*Anti-AChR antibodies
type II fiber atrophy
fix complement

S/S: ptosis, double vision

response to anticholinesterase agents , prednisone, plasmapheresis, resection of thymoma present

Answer 7

myasthenia gravis

Question 8

paraneoplastic syndrome

• small cancer of lung
• occurs in absence of neoplasia

proximal muscle weakness with autonomic dysfunction

normal response of postsynaptic membrane to anticholinesterase
-fewer vesicles released in response to each presynaptic action potential

electrophysiology: motor nerve stimulated at high rates, muscle response increased
- negative for AchR antibodies

Answer 8

lambert-eaton myasthenic syndrome

Question 9

characterized by widespread MSK pain and tenderness

fatigue
cognitive dysfunction
anxiety
depression

assoc:
chronic fatigue syndrome
chronic headaches
IBS

F>M; 9-1

*diagnosis of exclusion

S/S: pain all over, reduced functional capacity, increased evoke pain sensitivity, fatigue, sleep disturbances, tenderness is continuously variable

comorbid with chronic msk, psychiatric, infectious, metabolic

tx: pt ed, excercise,improve sleep, treat comorbidities

Answer 9

fibromyalgia