Muscle Disease

Question 1

List main muscle diseases (6)

Answer 1

Polymyalgia rheumatica
giant cell arteritis
polymositis
dermatomyositis
inclusion body myositis
fibromyalgia

Question 2

Polymyalgia Rheumatica

Answer 2

Common inflammatory condition causing myalgia at the hip and shoulder girdles

Question 3

Polymyalgia Reumatica Characteristics

Answer 3

Proximal myalgia of the shoulder and hip girdles
Morning stiffness >1hr
Strong relation to giant cell arteritis

Question 4

Polymyalgia Rheumatica: Epidemiology

Answer 4

Women

Over 50s

Question 5

Polymyalgia Reumatica Symptoms

Answer 5

Dramatic muscle stiffness
Shoulder and hip pain
No muscle weakness

Question 6

Polymyalgia Reumatica Investigation

Answer 6

Raised CRP

Raised ESR/PV

Question 7

Polymyalgia Reumatica Treatment

Answer 7

15mg prednisolone

Reduced over 18 months

Question 8

Giant Cell Arteritis

Answer 8

Commonest form of systemic vasculitis

Question 9

Giant Cell Arteritis Epidemiology

Answer 9

Older patients

Question 10

Giant Cell Arteritis Characteristics

Answer 10

Transmural inflammation of the intima, media and adventitia

Patchy infiltration by lymphocytes, macrophages and granulomas

Vessel wall thickening
- subsequent distal ischaemia

Patchy involvement

Question 11

Giant Cell Arteritis Symptoms

Answer 11

Visual Disturbances

• Diplopia
• As temporal artery supplies optic nerve
• Amaurosis fugal (painless or temporary loss of vision in one or both eyes)

Headaches
-continuous in occipital or temporal region

Jaw claudication
- due to maxillary artery ischaemia

Scalp tenderness
Fatigue
Malaise
Fever

Question 12

Giant Cell Arteritis investigations

Answer 12

Temporal artery biopsy

• mononuclear infiltration
• granulomatous inflammation

Raised ESR, CRP and PV

Question 13

Giant Cell Arteritis Treatment

Answer 13

If visual impairment
- 60mg prednisolone

No visual impairment
- 40mg prednisolone

Question 14

Polymyositis

Answer 14

Idiopathic weakness myopathy that causes symmetrical proximal muscle weakness

Question 15

Polymyositis Risk factors

Answer 15

High alcohol consumption

Illicit drug use

Question 16

Polymyositis Pathogenesis

Answer 16

CD8+ T cells and macrophages surround healthy muscle tissue and initiate a cytotoxic response

Question 17

Polymyositis Epidemiology

Answer 17

Females
>20
Age 45-60

Question 18

Polymyositis Symptoms

Answer 18

Symmetrical proximal muscle weakness in the upper and lower limbs
May have myalgia
Insidious onset
Dysphagia
- Oropharyngeal/ oesophageal involvement
ILD
Gradual onset
Fever
Weight loss
Raynaud's
Polyarthritis 
SOB
Cough

Question 19

Polymyositis Investigations

Answer 19

Inflammatory markers
Serum creatinine kinase
Auto-antibodies
- ANA
-Anti-Jo-1 (specific) 
-Anti-SRP (specific) 

MRI

• Muscle inflammation
• Oedema
• fibrosis
• calcification

Electromyography

Muscle Biopsy

Muscle strength testing

• confrontational
• isotonic

Question 20

Polymyositis Treatment

Answer 20

40mg prednisolone
Immunosuppressive drugs
- azathioprine
-methotrexate

IV immunoglobulin
Rituximab

Question 21

Dermatomyositis

Answer 21

Idiopathic weakness myopathy that causes symmetrical proximal muscle weakness with cutaneous manifestations

Question 22

Dermatomyositis Cutaneous Manifestations

Answer 22

V-shaped rash over chest

Gottron’s Papules

• Purple colouring of the skin over MCP and PIP joints
• Can be painful
• may bleed
• Often worsens in sunlight

Heliotrope rash

Question 23

Dermatomyositis: Main malignancy risks

Answer 23

Breast
Ovarian
Lung
Colon
Oesophageal
Bladder

Question 24

Inclusion body myositis

Answer 24

Type of inflammatory myopathy. Progressive muscle disorder.

NOT autoimmune

Question 25

Inclusion body myositis epidemiology

Answer 25

Commoner in men

Question 26

Inclusion body myositis Characteristics

Answer 26

``` Asymmnetrical. Generally affects the distal muscles. Slower onset than polymyositis. Responds poorly to therapy . CK levels are lower that polymyositis ```

Question 27

Fibromyalgia

Answer 27

Unexplained muscle condition causing widespread muscle pain and fatigue

Question 28

Fibromyalgia epidemiology

Answer 28

Females. | Young and Middle Age

Question 29

Fibromyalgia Aetiology

Answer 29

Unknown Disorder of cental pain processing Syndrome of central sensitivity

Question 30

Fibromyalgia sites

Answer 30

Neck Shoulders Lower back Chest wall

Question 31

Fibromyalgia symptoms

Answer 31

``` Persistent widespread pain >3 months on both sides of the body. Above and below the waist including axial skeleton Fatigue and unrefreshing sleep Cognitive difficulties Anxiety Depression IBS Migraines worse on exercise ```

Question 32

Fibromyalgia secondary to..

Answer 32

Rheumatoid Arthritis | Systemic Lupus Erythematous

Question 33

Fibromyalgia have lower threshold to...

Answer 33

Pain heat Noise Strong odours

Question 34

Fibromyalgia clinical signs

Answer 34

Excessive tenderness on palpitation | No other abnormalities

Question 35

Fibromyalgia Treatment

Answer 35

``` Education of self-management Graded exercise Atypical analgesia Gabapentin Pregabalin CBT ```