B6-074 Endocrine Myopathies Flashcards
most common endocrine myopathy
steroid myopathy
examination may show ataxic gait and poor cognition
hypoadrenalism
papilledema and other signs of increased ICP may be present
hyperadrenalism
long term insufficient function of the adrenal cortex leading to underproduction of corticosteroids
Addison disease
no response to ACTH stimulation test
Addison disease
adrenal failure or destruction or infiltration of the adrenal glands
primary adrenal insufficiency (Addison)
[…] adrenal insufficiency is caused by lack of ACTH stimulation from the pituitary
secondary
secondary adrenal insufficiency is relatively common due to
widespread use of exogenous corticosteroids
rhabdomyolysis has been reported in
hypothyroidism
**elevated CK and myoglobinuria
motor movements can have reduced velocity with delayed relaxation of muscle stretch reflexes
hypothyroidism
median neuropathy at wrist
myoedema
muscle enlargement
hypothyroidism
muscle weakness with atrophy of the pelvic girdle
hyperthyroidism
slowly progressive weakness, myalgia, rhabdomyolysis
hypothyroidism
slowly progressive proximal weakness, acute severe quadriparesis
hyperthyroidism
restrictive opthalmoparesis, proptosis
thyroid opthalamopathy
attacks of generalized weakness lasting hours
thyrotoxic periodic paralysis
tetany
cataracts
increased ICP
hypoparathyroidsim
creatine kinase is usually markedly elevated
hypothyroidism
in hyperthyroidism, creatine kinase is usually
normal
in hypothyroidism, an EMG can be used to differentiate
delayed muscle relaxation from myotonia
nonspecific type II muscle fiber loss with lipid storage
steroid myopathy
nonspecific type II muscle fiber atrophy with glycogen storage
hypothyroidism
vacuolar dilation of the sarcoplasmic reticulum
thyrotoxic periodic paralysis
rapidly evolving myopathy with deficient muscle fibers
corticosteroid therapy
slowly progressive proximal weakness, fatigue, muscle cramps
hypothyroidism
the EMG in hypothyroidism is often
normal
**doesn’t pick up myopathic processes
EMG reports which type of muscle fibers?
I
**this is why it can look normal, if damage in type II
hypothyroidism primarily atrophies type […] fibers
II
what changes may you see to type I fibers in hypothyroidism?
cores
**may also see expression of neonatal/embryonic fiber types
removal of the thyroid is a risk factor for the development of
hypoparathyroidism due to damage or accidental removal
tetany
spasms
fasiculations
Chvosteks
Trousseaus
hypoparathyroidism causing hypocalcemia
how does hypercortisolism cause striae?
decreases fibroblast activity –> decreases collagen formation
exertional rhabdomyolysis
hypothyroidism
hypothyroidism can cause atrophy of type […] muscle fibers
II
Addison disease is characterized by decreased levels of [2]
cortisol
aldosterone
fatigue
weight loss
skin hyperpigementation
hyponetremia
kyperkalemia
hypotension
Addisons
caused most often by autoimmune destruction of the adrenal glands
Addison disease
what test can differentiate primary, secondary, and tertiary adrenal insufficiency?
ACTH
most characteristic physical exam finding in patients with Addison disease
hyperpigmentation
**prohormone POMC is cleaved into ACTH and MSH, elevated MSH stimulates melanocytes and causes hyperpigmentation
thyroid hormone stimulates [3]
glycogenolysis
gluconeogenesis
lipolysis
decreased serum calcium is a feature of
hypoparathyroidism
increased serum calcium is a feature of
hyperparathyroidism
Addisons disease is usually treated with
hydrocortisone
the predominant manifestation of acute adrenal failure is […] and should be treated with […]
shock
IM hydrocortisone
combining any statin with […] greatly increases the chance of rhabdomyolysis
gemfibrozil
primary screening tests for Cushings [2]
24-urine free cortisol (or salivary)
dexamethasone suppression test
anti-thyroid drugs
methimazole
PTU
