Immune-mediated myopathies

Question 1

Name the 4 categories of idiopathic inflammatory myopathies

Answer 1

-Dermatomyositis
-Overlap myositis
-Anti-synthetase syndrome
-Immune-mediated necrotizing myopathy

Question 2

Name 4 dermatological manifestations of dermatomyositis.

Answer 2

-Gottron sign
-Heliotrope sign
-V sign
-Shawl sign
-Holster sign
-Calcinosis cutis
-Mechanic’s hands
-Poikiloderma
-Alopecia

Question 3

What 2 skin findings are characteristic of anti-MDA-5 dermatomyositis?

Answer 3

-Palmar papules
-Fingertip ulcerations

Question 4

Nail bed telangiectasia and cuticle overgrowth are more common in which immune-mediated myopathy?

Answer 4

Anti-Mi-2 dermatomyositis

Question 5

The most severe interstitial lung disease occurs in which immune-mediated myopathies (3)?

Answer 5

Anti-MDA-5 dermatomyositis
-Antisynthetase syndrome
Overlap myositis with systemic sclerosis

Question 6

When assessing for immune-mediated myopathies, creatine kinase can be :
-Normal in…
-Very high in…

Answer 6

-Normal in dermatomyositis and antisynthetase syndrome
-Very high in immune-mediated necrotizing myopathy

Question 7

Which two antibodies are found in the adult and juvenile form of dermatomyositis?

Answer 7

-Anti-TIF1 antibody
-Anti-NXP-2 antibody

Question 8

Which two antibodies in dermatomyositis are associated with the amyopathic presentation?

Answer 8

-Anti-MDA-5 antibody
-Anti-SAE antibody

Question 9

Glomerulonephritis is seen most commonly in which inflammatory myopathy?

Answer 9

Anti-U1 RNP antibody overlap myositis

Question 10

What are the 5 characteristic features of anti-synthetase syndrome?

Answer 10

-Myositis
-Interstitial lung disease
-Raynaud phenomenon
-Arthralgia
-Mechanic’s hands

Question 11

What are the 3 antibodies associated with immune-mediated necrotizing myopathy?

Answer 11

-Anti-SRP antibodies
-Anti-HMG-CoA-reductase antibodies
-Anti-mitochondrial antibodies

Question 12

Patients with which inflammatory myopathies should undergo cancer screening?

Answer 12

-Adults >40 years old with dermatomyositis (especially anti-TIF1-gamma and anti-NXP2 antibodies)
-All adults with seronegative or anti-HMG-CoA reductase antibodies

Question 13

What is the treatment for inflammatory myopathies?

Answer 13

IVSM 1 g IV DIE x 3-5 days followed by prednisone 1-1.5 mg/kg DIE x 6-8 weeks (or no IVSM to begin with) followed by slow taper