An 82-year-old man presents with 8 weeks of periorbital edema, 6 weeks of rash, and 2 weeks of bilateral shoulder and arm aches and weakness. What is the diagnosis?
a. Polymyalgia rheumatica
b. Inclusion body myositis
c. Hypothyroidism
d. Polymyositis
e. Dermatomyositis
Dermatomyositis
Answer: e
• Three causes of idiopathic inflammatory myopathy:
Dermatomyositis (DM)
Polymyositis
Inclusion body myositis
• Dermatomyositis has a bimodal age distribution
• Skin findings associated with DM:
Heliotrope hue of the eyelids
Rash of the metacarpophalangeal and proximal interphalangeal joints (Gottron’s papules)
Photosensitivity dermatitis of the face
• Proximal myositis with associated pain and weakness is characteristic of DM
• The serum creatine kinase and aldolase values are usually increased in DM
• The anti-Jo1 antibody is present in 25% of patients with DM
• The electromyogram is characteristic, but not diagnostic, of the inflammatory myopathies
• A muscle biopsy is suggested for all patients with inflammatory myopathy
• Patients with DM have an increased risk for cancer
• DM is treated with immunosuppressive drugs