(above left: heliotrope rash, above right: Gottron's papules)
Classic skin manifestations of Dermatomyositis include:
- Gottron's papules: symmetric, erythematous and scaly appearance over the MCPs/PIPs/DIPs. You may also see this on the elbows.
- Heliotrope rash: classically described as a 'violaceous' rash on the eyelids.
- Shawl Sign: Imagine your patient is wearing a shawl - there is often erythema in a 'V' shaped distribution over where a shawl would be worn.
- More Subtle Signs: You may hear the term "Mechanics Hands" which refers to a rugged and cracked appearance of the lateral aspect of the fingers, usually at the end - and as the name implies, this is what the hands of a manual labourer may appear like. Another finding is periungual edema, and dilated periungual vessels.
*A good way to test for proximal muscle weakness in this condition is to have a person sit in a chair with their arms folded across their chest, and have them attempt to stand up.*Remember that many patients with Dermatomyositis have an underlying malignancy, and the diagnosis of Dermatomyositis should prompt an age-appropriate and risk-factor-appropriate malignancy screen. This link shows some new data relating the two conditions.
(periungual vascular changes pictured left)