One of the great things about rheumatology is the power we invest in our physical exam. We are detectives, systematically and meticulously looking for outer signs of inner disease. It is a throwback to how medicine was practiced in the "olden days," prior to the advent of MRI scans, sophisticated laboratory tests and even microscopes. So much can be told by the presence of a skin rash, the colouring of a patient's nailbeds, or the firmness of their skin.
One disease in which the physical exam can essentially make a diagnosis is dermatomyositis (DM). There are several skin rashes that are typical of DM, and which have been described in DM patients, including Gottron's papules and sign, heliotrope rash, V-sign, Shawl sign, and the Holster sign. The Myositis Center at Johns Hopkins University recently described a new skin eruption (poster abstract #305) termed the "Sleeve Sign.
The Hopkins group analyzed a cohort of 262 patients with a Bohan and Peter diagnosis of definite, probable, or possible DM, or who had a diagnosis of amyopathic DM who had undergone a thorough skin examination between 2004-2015. Twenty-seven patients had a history of a violaceous or erythematous rash on their upper arm, aptly termed the Sleeve Sign since its location was consistent with the contour of patients' sleeves. These patients also had other skin manifestations of DM present in varying degrees, including the heliotrope rash (44.4%), malar rash (51.9%), Gottron's sign (85.2 %), V-sign (59.3%), Shawl sign (55.6%), and Holster sign (25.9%). Sixty-five percent of patients had the anti-TIF-1 gamma antibody present, which is an autoantibody associated with inflammatory myositis.
So what does this mean? In the right clinical context, "the Sleeve Sign" may reinforce your diagnosis of DM. It is frequently found with other skin findings of DM. So, in a patient where your suspicion of DM is high, put your detective skills to work and search for other key exam findings. In the words of Wilburt C. Davison, founder and dean and Duke University Medical Center,"The skin is a mirror of the body. Look to the skin for specific manifestations of diseases."