Management of cutaneous dermatomyositis in adults with isolated skin involvement

IVIG: intravenous immune globulin; MMF: mycophenolate mofetil.
* We typically use topical calcineurin inhibitors for patients who do not improve with topical corticosteroids or for long-term topical therapy in skin areas that are prone to cutaneous atrophy (eg, face, intertriginous skin).
¶ Some patients with very mild skin disease achieve sufficient improvement without the addition of systemic therapy, and a 3-month trial of photoprotection, antipruritic therapy, and topical therapy is a reasonable alternative for these patients. However, most patients require systemic therapy to suppress cutaneous disease.
Δ Approaches to therapy vary. Some clinicians begin methotrexate and hydroxychloroquine simultaneously while others opt to begin hydroxychloroquine if there is an insufficient response to methotrexate.
◊ Refer to UpToDate content on the management of cutaneous dermatomyositis for details on appropriate tapering regimens.
§ In our experience, combination therapy with hydroxychloroquine and methotrexate typically provides a more substantial response than combination therapy with hydroxychloroquine and quinacrine. Therefore, we tend to favor the addition of methotrexate as disease severity increases. Consideration of patient comorbidities and likelihood to tolerate each drug also influences selection between these treatments. Switching from hydroxychloroquine to chloroquine is an alternative next step. This is based upon the perception that some patients who do not respond to hydroxychloroquine can respond to chloroquine; however, data to confirm greater efficacy of chloroquine are lacking.
¥ Clinicians with expertise in dermatomyositis generally consider IVIG the most effective treatment and treatment of choice. However, comparative studies have not been performed. The need for intravenous administration and the high cost of IVIG limit use in some patients.
‡ Due to the relatively slow onset of action of MMF, preceding systemic therapy (eg, methotrexate, antimalarial) is often continued while awaiting the drug's onset of action in an attempt to reduce risk for disease flares.
† Alternative therapies include systemic immunosuppressants (eg, azathioprine, cyclosporine, tacrolimus, sirolimus, cyclophosphamide, chlorambucil, Janus kinase inhibitors, rituximab) and dapsone. Due to limited or conflicting evidence for efficacy and/or risk for adverse effects, use of these agents are generally reserved for patients who have failed or who are poor candidates for IVIG and MMF.