Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

724: Medical Lectures > Myopathies > Flashcards

Myopathies Flashcards

You may prefer our related Brainscape-certified flashcards:
USMLE® Step 1 flashcards
1
Q

MUSCULAR DYSTROPHIES

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are muscular dystrophies characterized by?

A

Progressive muscle weakness and wasting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What serum level is oftentimes elevated in muscular dystrophies?

A

creatine kinase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

A genetic defect on the short arm of the X chromosome has been identified in _____ dystrophy

A

Duchenne

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

This genetic defect found in Duchenne’s cdes for what protein? What is the affect?

A

dystrophin

Levels are markedly reduced or absent in the muscle of these patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Are dystrophin levels affected in the Becker variety of muscular dystrophies?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What medication improves muscle strength and function in boys with Duchenne dystrophy?

A

Prednisone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What things must be avoided and what things are encouraged in these patients?

A

Bed rest is associated with a worsening of the disease

PT and orthopedic procedures may help counteract deformities or contractures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

MYOTONIC DYSTROPHY

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Myotonic dystrophy is a slow, progressive, inherited disorder that manifests in the __ or __ decade of life

A

3rd or 4th

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How many types of myotonic dystrophies have been determined?

A

2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are 3 muscular symptoms of myotonia?

A
  • muscle stiffness
  • marked delay in muscle relaxation following contraction
  • weakness and wasting of the facial, SCM, and distal limb muscles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are 6 clinical features of myotonia?

A
  • cataracts
  • frontal baldness
  • testicular atrophy
  • diabetes mellitus
  • cardiac abnormalities
  • intellectual changes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What drug may be helpful when myotonia is disabling?

A

Sodium channel blockers such as…

  • phenytoin
  • procainamide
  • mexiletine
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

True or False

Associated weakness and the course of myopathy are influenced by treatment

A

False

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

MYOTONIA CONGENITA

A
17
Q

Myotonia congenita is commonly inherited as a _____ trait

A

dominant

18
Q

The responsible gene on chromosome 7 is responsible for what?

A

encoding a voltage-gated chloride channel

19
Q

When do symptoms of myotonia congenita develop?

A

early childhood

20
Q

What are the 2 signs and symptoms of myotonia?

A
  • muscle stiffness that is enhanced by cold and inactivity

- muscle hypertrophy

21
Q

What relieves muscle stiffness?

A

exercise

22
Q

What durgs are used to treat myotonia congenita?

A
  • procainaminde
  • tocainide
  • mexiletine
  • phenytoin
23
Q

INCLUSION BODY MYOSITIS

A
24
Q

Inclusion body myositis begins _____, usually after middle age

A

insidiously

25
Q

What is the main characteristic of inclusion body myositis?

A

progressive proximal weakness of first the LEs and then the UEs

26
Q

Where does muscle weakness often begin in inclusion body myositis? (LE and UE)

A
  • the quadriceps femoris

- forearm flexors

27
Q

What confirms the diagnosis of inclusion body myositis?

A

muscle biopsy

28
Q

What drug therapy has been found to have a mild benefit on inclusion body myositis?

A

Intravenous immunoglobin (IVIG) therapy

29
Q

MITOCHONDRIAL MYOPATHIES

A
30
Q

What can be seen on pathologic examination of skeletal muscle with the modified Gomori stain in patients with mitochondrial myopathies?

A

characteristic “ragged red fibers” containing accumulations of abnormal mitochondria

31
Q

What 2 signs do patients with mitochondrial myopathies present with?

A
  • progressive external ophthalmoplegia

- limb weakness that is exacerbated or induced by activity

32
Q

Some patients with mitochondrial myopathies present with what type of dysfunction?

A

CNS (epilepsy, ragged red fiber syndrome, or MERRF)

33
Q

What does the acronym MELAS stand for?

A

Myopathy
Encephalopathy
Lactic Acidosis
Stroke-like episodes

34
Q

What type of patients do mitochondrial myopathies develop?

A
  • AIDS patients receiving zidovudine

- HIV1 patients receiving HAART

35
Q

ASSOCIATED MYOPATHIES

A
36
Q

What are some associated disorders myopathy may occur with?

A
  • chronic hypokalemia

- endocrinopathy

37
Q

Myopathy may develop in patients taking what drugs?

A
  • corticosteroids
  • chloroquine
  • colchinice
  • clofibrate
  • emetine
  • aminocaproic acid
  • statin drugs
  • bretylium tosylate
38
Q

Weakness due to myopathy is mainly _____.

A

proximal

39
Q

Preexisitng myotonia may be exacterbsated or unmasked by what drugs?

A
  • depolarizing muscle relaxants
  • beta-blockers
  • fenoterol
  • ritodrine
  • diuretics

724: Medical Lectures (42 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions