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Flashcards in Myopathy Deck (93)
1

What is the most common distal symmetric polyneuropathy?

DM complication

2

What is the difference between positive and negative symptoms with polyneuropathy?

Positive = gain of pain etc

Negative = loss of sensation, motor etc

3

What are the s/sx of large fiber neuropathy? Small fiber?

Large fiber = loss of myelinated fibers (proprioception)

Small = Loss of unmyelinated fibers (loss of pain, light touch)

4

True or false: symmetric proximal neuropathy excludes DM as the cause

False

5

Focal and multifocal neuropathies are usually caused by what insult?

ischemic insult

6

What is peroneal neuropathy?

Entrapment of nerve at fibular head

7

What is the prevalence of peripheral neuropathy in DM pts?

near 100%, but variable expressivity

8

Which is more common with DM neuropathy: pain and paresthesias, or sensory/motor loss?

Pain and paresthesias

9

What are the risk factors for developing DM neuropathy? (4)

-Tall
-Male sex
-duration of disease
-age

10

What is the polyol pathway of DM neuropathy pathogenesis?

Elevated BG levels lead to a high nerve glucose concentration, which is converted for sorbitol by aldose reductase

Resulting decrease in myoinositol interferes with Na pump

11

What is the microvascular theory of DM neuropathy?

Pathologic changes in diabetic nerves include capillary basement membrane thickening and resulting neuronal ischemia

12

What is the glycosylation end-product theory of DM neuropathy?

Chronic intracellular hyperglycemia leads to glycosylation end products which deposit around peripheral nerves

13

What is the usual presentation of DM neuropathy?

Insidious onset of stocking glove pattern of neuropathy

14

What are the labs that should be obtained with peripheral neuropathy?

CBC
ESR

15

What is the vitamin that should always be checked for with neuropathies?

B12 and folate

16

What is the role of EMGs with evaluating neuropathies?

-May confirm symptoms are related to neuropathy
-Distinguish between axonal and demyelinating neuropathies

17

What is the treatment for Peripheral neuropathies 2/2 immune mediated diseases?

IVIG or plasma exchange

18

Is lowering BG levels to treat peripheral neuropathies more effective in DM I or DM II?

More effective in DM I

19

What are the two major antidepressants used to treat symptoms with peripheral neuropathies?

Tricyclics
Cymbalta

20

What are the antiepileptic drugs that are used to treat neuropathic pain?n (3)

-Pregabalin
-Gabapentin
-Carbamazepine

21

What is the treatment for absence seizures?

Ethosuximide

22

What is the treatment for trigeminal neuralgia, and for partial and complex seizures?

Carbamazepine

23

What are the two major analgesics for neuropathy?

-Tramadol
-Narcotics

24

What are the two topical agents used to treat neuropathies?

-Capsaicin
-Lidocaine

25

What is the bimodal age onset for MG?

15-30 y/o women
60+ yo men

26

What is the most common presentation of MG?

Lid ptosis or diplopia with fatigue

27

What are the usual bulbar s/sx with MG? (2)

-facial weakness/dysarthria
-Neck flexor weakness

28

How do you assess for ocular motor weakness with MG?

-Upgaze for 30-60 seconds leads to asymmetric ptosis
-facial muscle weakness

29

What are the oropharyngeal s/sx of MG? (2)

-Flaccid dysarthria with nasal regurgitation

-Jaw weakness

30

Which is usually affected more often with MG: upper or lower extremities?

Upper extremities--particularly the deltoid and wrist extensors

31

What is myasthenia crisis?

Respiratory failure 2/2 intercostal and diaphragmatic weakness

32

How do you monitor myasthenia crisis?

Follow VC and NIF (negative inspiratory forces)

33

What are the antibodies that mediate MG?

Anti-ACh antibodies

34

What is the diagnostic drug and treatment drug for MG?

-Edrophonium is test
-Pyridostigmine is treatment

35

How do you diagnose MG? (3)

-Edrophonium test
-Electrodiagnostic repetitive stimulation
-Anti-ACh antibodies test

36

True or false: there is a good correlation between the titer levels of Anti-ACh antibodies and the severity of MG

False

37

What are the CT chest findings of MG?

Thymomas

38

What is the treatment for MG?

Cholinesterase inhibitors--Pyridostigmine

39

What are the side effects of Pyridostigmine?

Wet picture--GI hyperactivity

40

What is the immunotherapy/surgical treatment for MG?

Thymectomy can reduce the immune response

41

What is the role of immunosuppressants in the treatment of MG?

All can improve weakness, but carry their own side effects.

42

What is the treatment for a MG crisis? (2)

-Plasma exchange
-IVIG

43

Are myopathies usually bilateral or unilateral? Proximal or distal?

Bilateral
Proximal

44

What is the characteristics gait with myopathy?

Waddling gait since it involves the stronger truncal muscles

45

Is there preserved sensation/reflexes with myopathies?

Yes

46

Are CKs useful for diagnosing myopathies

Yes--elevated in majority of myopathies, but also elevated in rhabdo and seizures

47

What are the primary inflammatory myopathies?

Dermatomyositis
Polymyositis
Inclusion body myositis

48

What is polymyositis? Progression? S/sx?

Polymyositis is an inflammatory myopathy mediated by cytotoxic T cells with an as yet unknown autoantigen

Subacute proximal weakness--painless

Spares eye, face
Neck weakness

49

True or false: there is a high incidence of malignancy causing polymyositis

False

50

How do you diagnose polymyositis? (3)

-Elevated CK
-EMG with myopathic and inflammatory changes
-Muscle bx (definitive)

51

What is the treatment for polymyositis?

Immunosuppressants

52

When does dermatomyositis usually present? Cause?

-Childhood or adult onset
-Unknown, but may be related to viral or bacterial infx causing autoimmune response

53

What are the s/sx of dermatomyositis?

skin rash and proximal muscle weakness

54

What is the treatment for dermatomyositis?

Immunosuppressants

55

When does inclusion body myositis usually present?

Adult onset

56

What are the s/sx of inclusion body myositis?

Finger/wrist flexor and quad weakness

57

How does inclusion body myopathy respond to steroids?

Does not

58

How does the progression of disease differ between polymyositis, dermatomyositis, and inclusion body myositis?

Polymyositis and dermatomyositis are subacute in onset, while inclusion body is a slow, chronic condition

59

What are the muscles that are usually affected with inclusion body myositis?

Finger/wrist flexor weakness

60

What is the major risk factor for steroid myopathy?

More than 30 mg of prednisone QD for more than 2 months

61

What is the usual onset of steroid induced myopathy

Subacute to chronic presentation of proximal weakness

62

What are the EMG findings of steroid myopathies?

Normal usually

63

What are the CK findings of steroid myopathy?

Normal

64

True or false: all cholesterol lowering agents have the potential to cause myopathic effects

True

65

What is statin myopathy?

Any muscle complaint related to statin use

66

What is the difference between myalgias and myositis?

Myositis has CK elevation

67

What are the CK level with rhabdo?

more than 10x normal with elevated Cr

68

What is the treatment for statin myositis?

If rhabdo, d/c drug and change

69

Unless CK elevates (__)x with statin use, there is no need to stop statin therapy

10x

70

What are the motor symptoms of motor neuron disease?

Asymmetric
Varibale location
Atrophy
Fasciculations

71

What are the motor symptoms of neuropathies (symmetric/asymmetric? Distal or proximal?)

Symmetric
Distal more than proximal

72

What are the motor symptoms of myopathies (symmetric/asymmetric? Distal or proximal?)

Symmetric
Proximal greater than distal

73

What are the sensory symptoms of motor neuron diseases?

Absent

74

What are the sensory symptoms of neuropathies?

-Paresthesias
-Dysesthesias
-Autonomic s/sx

75

What are the sensory symptoms of NMJ diseases?

Absent

76

What are the sensory symptoms of myopathies?

Absent

77

What are the reflex findings with Motor neuron disease?

Hyperactive

78

What are the reflex findings with neuropathies?

Diminished

79

What are the reflex findings with NMJ/myopathies

normal

80

What is asymmetric proximal motor neuropathy (diabetic amyotrophy)?

Prominent anterior thigh pain with weakness of quadriceps/iliopsoas, with loss of patellar reflex

81

True or false: the loss of the calcaneal reflex is always pathologic

false--very commonly lost with normal aging process

82

How can you tell if MG patients will progress to a systemic form of the disease?

83% of patients will progress to generalized disease in less than 36 months

83

What is the manifestation of MCAD deficiency?

Non-ketotic hypoglycemia

84

What is the classic presentation of Carnitine deficiency?

Non-ketotic hypoglycemia

85

What is type I - V GSD?

I = glucose-6-dehydro deficiency
II = Acid maltase (alpha glucosidase deficiency)
III = Cori disease (debranching)
V = McArdle's disease (glycogen phosphorylase)

86

What is the cause and presentation of LHON?

Sudden onset of blindness in young adults 2/2 mutations in subunits of complex I of the ETC

87

What is the cause and presentation of MERRF?

-myoclonic epilepsy and ragged red fibers
0point mutation for lysine tRNA leads to mitochondria containing paracrystalline arrays, and diminished cytochrome oxidase deficiency

88

What is the cause and presentation of MELAS?

-Mitochondrial encephalopathy, lactic acidosis, stroke-like activity
-point mutation in leucine tRNA

89

Both MELAS and MERRF have ragged red fibers. How can you differentiate the two?

Cytochrome oxidase activity is normal in MELAS, but diminished in MERRF

90

True or false: there are usually no malignancies associated with inclusion body myositis

True

91

What causes inclusion body myositis?

T cells mediated attacked against muscles, causing vacuoles to develop in muscles with abnormal protein deposits

92

What are the major muscles that are affected with NMJ disorders?

Cranial, limb girdle, and proximal muscles

93

Which usually has autonomic s/sx: MG or Eaton-Lambert?

Eaton-Lambert