Response to: 'Correspondence on 'EULAR/ACR classification criteria for adult and juvenile idiopathic inflammatory myopathies and their major subgroups'' by Irfan et al.

We have with interest read the ‘Correspondence on “EULAR/ACR classification criteria for adult and juvenile idiopathic inflammatory myopathies and their major subgroups” by Irfan et al ’ with subtitle: improving the subtyping of dermatomyositis in the 2017 EULAR/ACR classification criteria for juvenile and adult idiopathic inflammatory myositis: value of non-classic cutaneous findings, to be published in Annals of the Rheumatic Diseases .1 Here, the authors present performance of the EULAR/ACR classification criteria2 in a cohort from India of 26 consecutive adult patients with idiopathic inflammatory myopathies (IIM). Patients with characteristic skin rashes (those included in the EULAR/ACR criteria as well as in the older Bohan and Peter criteria) were classified as having dermatomyositis (DM). The remainder of the patients were classified as polymyositis (PM) (n=12). All patients had documented muscle weakness. Of the 12 patients classified as PM, seven had non-classical skin rash such as generalised erythematous rash or malar rash and had been given the diagnosis DM by their physician. Moreover, five of these seven patients had myositis-associated autoantibodies that largely supported the clinical diagnosis of DM. The authors conclude that the sensitivities of Gottron’s papules (60%–80%) and heliotrope rash (30%) are low. The authors suggest …