Annular subacute cutaneous lupus erythematosus lesions and polymyositis onset in a patient with primary Sjögren's syndrome: how should this unusual association be classified?

Classification of the wide variety of autoimmune diseases that can occur before or after the onset of Sjögren’s syndrome (SS) is currently debated within the conventional SS criteria or as primary SS ( pSS) developing autoimmune disease or as ‘associated-overlap’ with other systemic autoimmune diseases. There is also debate on whether or not to consider annular polycyclic subacute cutaneous lupus erythematosus (SCLE) and annular erythema associated with Sjögren's syndrome (AESS) as a spectrum linked to Ro-SSA and/or La-SSB auto-antibodies (SSA/SSB auto-ab). We present the case of a 55-year-old female patient, with pSS positive for SSA and SSB auto-ab, who developed chronic relapsing polymyositis and atypical annular non-polycyclic SCLE lesions resembling AESS, which seemed to suggest a common spectrum. While a chronic-progressive polymyositis may be generally accepted as a relatively rare myositis complicating pSS, interpretation of annular lesions of non-systemic SCLE in SS patients might actually be underestimated as pSS skin manifestation likely related to SSA/SSB auto-ab.