Pathophysiology One Flashcards
what are the 2 classifications of myopathy?
- heredity
- acquired
what are some types of hereditary myopathies?
ccmmmm
- congenital myopathy
- muscular dystrophies
- myotonia and channelopathies
- primary metabolic myopathies
- mitochondrial myopathies
what are some types of acquired myopathies
- inflammatory myopathies
- infectious myopathies
- endocrine myopathies
- secondary metabolic myopathies
- drug induced and toxic myopathies
_________ is a broad term for any muscle disorder present at birth
- congenital myopathy
- primarily affects skeletal muscle fibers and causes muscular weakness and/or hypotonia
_____________ is one of a group of muscle diseases know a the inflammatory myopathies, which are characterized by chronic, progressive muscle inflammation accompanies by muscle weakness
inclusion body myositis (IBM)
A positive gowers sign tells you what?
there is proximal muscle weakness
what 2 types of myopathies are characterized by loss of muscle mass?
- atrophic myopathies (loss of CSA secondary to underlying disease or metabolic stress)
- destructive myopathies
what 2 types of myopathies are characterized by having normal muscle mass?
- channelopathies
- metabolic myopathies
what are 3 types of channelopathies
- Ca+ release
- Cl- channel
- Na+ channel
What are 2 types of metabolic myopathies
- glycogenoses (McArdie and Tauri)
- mitochondrial
what are 3 types of neuropathic muscle diseases
- anterior horn cell (SMA)
- peripheral neuropathies
- neuromuscular junction (Myasthenia gravis)
what is an example of a common muscle missing at birth?
is the deficiency usually uni or bilateral?
- palmaris longus
- unilateral
what are 3 types of idiopathic autoimmune myopathies we focus on?
dermatomyositis
polymyositis
inclusion body myositis *
what are some general characteristics of idiopathic autoimmune myopathies?
- typically myopathy in proximal muscles, usually symmetrically
- weakness progresses faster than in muscular dystrophy, rarely occurs acutely
- severe cases associated with muscle wasting
- all treated with corticosteroids or immunosuppressants
which pathology is characterized by a rash, f>m, fine motor impairement, and perimysial inflammation
dermatomyositis
which myopathy occurs after the 2nd decade of life and affects proximal muscle before distal muscles
polymyositis
which pathology affects m>w, w>b, distal before proximal, 50’s, falls common due to quadricep weakness, and progresses slowly
inclusion body myositis
hyperkalemia?
- elevated K level
hypokalemia
- low K level
what is the cause of periodic paralysis
hyperkalemia and hypokalemia
what is the etiology of kyper and hypokalemia?
- fluid loss, disease, meds, hereditary
onset of periodic paralysis is often due to?
exercise
what disease happens in type 1 muscle and is due to an issue with RYR1 releasing Ca?
core myopathy/central core disease
what is malignant hyperthermia causes by?
RYR mutation
- body temp goes crazy under anesthetics and the fever can kill you
what is the opposite of core myopathy?
brody syndrome
what is brody’s syndrome
progressive muscle stiffness and pain during exercise
what disease happens in type 2 muscle and is an issue with SERCA pumping Ca+ back into the SR?
brody’s syndrome
do malignant hyperthermia, hypo/hyperkalaemic paralysis and myotonia cause change in muscle mass?
no because they are all channelopathies
what disease is characterized by an issue with Cl conductance and issues repolarizing the cell.
myotonia congenita
what are two types of myotonia congenita
- thomsen disease
- becker disease
is becker or thomsen disease more severe?
becker
what do people with thomsen disease struggle with?
- falls, grasping objects, chewing
- muscle size and strength
what do people with becker disease primarily struggle with?
- gait issues and unprotected falls
thomsen and becker diseases are due to _____ conductance problems
Cl-
what is the most common myopathy?
alcoholic myopathy
T or F: alcohol influences multiple aspects of both the anabolic and catabolic arms of the pathway
T
T or F: cirrhosis of the liver is more common than myopathy in alcoholics
F, myopathy is more common
what are the two forms of alcoholic myopathy?
chronic and acute
is chronic or acute alcohol myopathy characterized by being painless, mild proximal weakness and affects pelvic more than shoulder girdle musculature
chronic
is acute or chronic alcohol myopathy characterized pain, muscle swelling, false DVT positive, compartment syndrome, rhabdomyolysis and usually affects 1-2 muscles
acute
what are some pathogenic mechanisms leading to alcohol-induced muscle damage
- carbs, protein, and energy metabolism
- oxidative balance
- gene dysregulation
- cell turnover
- signal transduction
- apoptosis
increased alcohol abuse = ________ strength
decrease
how does alcohol abuse affect muscle synthesis
decreases it
does strength improve with abstinence and low-dose controlled consumption
yes
does alcohol abstinence restore protein synthesis?
yes
is there increased skeletal muscle apoptosis in alcoholics?
yes, TUNEL assay proves that
is skeletal muscle apoptosis between chronic alcoholics with and without myopathy similar?
no those with myopathy have much larger rates of apoptosis
how is the degree of alcoholic myopathy rates
mild, moderate, sever
are men and women equally affected by alcoholic myopathy
no, men affected more than women
what exacerbates alcoholic myopathy
critical illness
hospitalization
infections (HIV)
malnutrition
inactivity
what mitigates alcoholic myopathy
- exercise
- myostatin inhibitors
- good nutrition
what are the 3 types of ehlers-danlos syndrome we need to remember
hypermobility
classical
vascular
hypermobility EDS is characterized by:
extreme flexibility
classical type EDS affects what type of collagen
V and 1
skin hyperextensibility, widened atrophic scars, and joint hypermobility are characteristics of what type of EDS
classical type
what type of collagen is affected in vascular EDS
3
most serious form, arterial/organ/tendon/muscle rupture, digit joint hypermobility are characteristics of what type of EDS?
vascular
what are two types of carb metabolism myopathy we are concerned with
McArdle disease
Tauri disease
what is affected in McArdle disease? why is that bad?
myophosphorylase
body can’t break glycogen down into glucose in the muscles
what is affected in Tarui disease and why is that bad?
phosphofructokinase (PFK) enzyme deficiency
that’s bad because this enzyme is needed in glycolysis. if we don’t have it your body can’t use glucose as fuel
T or F: lipid storage diseases can happen anywhere
T
