Polymyositis And Dermatomyositis - Week 17

Question 1

What is Polymyositis?

Answer 1

Autoimmune connective tissue disease
Chronic inflammation of muscles

Question 2

What is Dermatomyositis?

Answer 2

Autoimmune connective tissue disorder
Chronic inflammation of skin and muscles

Question 3

Epidemiology of poly and Dermatomyositis?

Answer 3

Can develop at any age
Women more likely

Question 4

What is the pathophysiology of poly and Dermatomyositis?

Answer 4

Autoimmune
Both can be caused by an underlying malignancy

Question 5

Presentation of Polymyositis and Dermatomyositis?

Answer 5

(Dermatomyositis only)

Skin involvement:

Gottron lesions (knuckles, elbows, knees)
Photosensitive erthyemataous rash
Purple rash on face and eyelids (heliotrope)
Periorbtial oedema
Subcutaneous calcinosis

Muscle fatigue and weakness
Insidious (3-6 month) onset
Usually painless
Proximal muscle weakness
Dysphonia and swallowing affected (other striated muscle damage)

Question 6

Investigations for Polymyositis and Dermatomyositis?

Answer 6

Elevated creatine kinase
Muscle biopsy
Positive antibodies from myosotis lines blot

Question 7

What are the positive antibodies in poly and Dermatomyositis?

Answer 7

Anti-Jo-1 ( Polymyositis and Dermatomyositis)
Anti-Mi-2 (Dermatomyositis)
Anti-nuclear (Dermatomyositis)

Question 8

Management of poly and Dermatomyositis?

Answer 8

Corticosteroids - prednisolone

Immunosuppressant
IV immunoglobulins
Biologics

Question 9

Prognosis of poly and Dermatomyositis?

Answer 9

Continual management, could have flare ups.

Maintain muscle strength