Muscle Disease

Question 1

Cardinal featuand other features?

Answer 1

Cardinal- 5
Progressive muscle weakness
Predominately proximal
BL and symmetrical muscle involvement
Waddling gate,govern’s gait
Knee jerk more affected than ankle

Other- 5
Dysphagia
Muscle pain and tenderness
Normal tendon and plantar response
Absence of numbness
Absence of bladder and bowel movement

Question 2

Ix?

Answer 2

1.serum muscle enzymes
-CPK/CK 3
-LDH
-aldoLase

2.EMG
myopathic changes

3.muscle biopsy
Evidence of inflammation,myopathic or dystropic changes ,mitochondrial cytopathy,enzyme def,storage disorders
4.MRI. Of muscle
5.ecg and echo in dystrophies

Question 3

Classification of dystrophies?

Answer 3

Inherited-3
Acquired-5

Question 4

Inflammatory myopathies classification?

Answer 4

Idiopathic-3
-polymyositis
-dermatomyositis
-inclusion body myositis

Secondary-2
-myositis in infection
-myositis associated with connective tissue diseases

Question 5

Pathophysiology of polymyositis and dermatomyositis?

Answer 5

Osmosis

Question 6

Clinical features of PM/DM?

Answer 6

7
-commonest in 4th and 5th decades
-F:M 2:1
-insidious onset
-symmetrical muscle involvement
-pain,tenderness,weakness, of proximal muscles
-severe disease can involve respi and cardiac muscles
-constitutional symptoms- fever,athralgia,LOW

Question 7

Skin manifestations of DM?

Answer 7

Helicopter rash
Peri orbital edema
Shawl sign
Gottron’s sign
Mechanic’s sign
Ragged nail folds and dialated cappilaries

Question 8

Ix for PM/DM?

Answer 8

1.ESRBn CRP (elevated or mostly N)
2.very high CPK
3.EMG
4.muscle biopsy
DM-perifascicularbaround the blood vessel
PM-diffuse within muscle fascicles
5.Ab
ANA (80%)
Anti synthetase ab (anti jo)

Question 9

Mx of PM/DM?

Answer 9

4
-early aggressive tx associated with better outcome
-corticosteroid (1st line)
-other immunosuppressants (methotrexate,cyclosporin,cyclophosphamide)
-Monitor muscle strength and function (CPK,CRP,ESR,VITAL CAPACITY)

Question 10

Infective causes of muscle disease?

Answer 10

1.viral -influensa,coxsackie,echo,EBV
2.parasitic-toxoplasmosis,trichinosis
3.bacterial-clostridium,TB,strep,staph
4.fungal

Question 11

Myopathies in endocrine and metabolic disorders?

Answer 11

6
Thyrotoxicosis (cpk is usually N)
Hypothyroidism (^ cpk)
Cushing’s
Hyper parathyroidism
Osteomalacia/rickets
Hypokalemia

Question 12

Drug induced myopathies?

Answer 12

7
Steroids
Statins
Anti malaria
Clofibrate
Colchicine
Zidovudine
Alcohol excess

Question 13

Myotonic dystrophy?

Answer 13

11 (photo)

Question 14

Mucle dystrophies? (Dushene and bekers)

Answer 14

Osmosis
Special features 2
Difference of two 3
Pathophysiology
Clinical features
-short term 3
-long term 5
Diagnosis 4
Tx 2

Question 15

Classification of disorders of NMJ?

Answer 15

Pre synaptic - 3
-lambert-eaton myasthenic xd
-snake venom (beta-bungaratoxin)
-bottulism

Post synaptic- 2
-MG
-snake venom (alpha bangaratoxins)