[Annular erythema in Sjögren syndrome. A variant of cutaneous lupus erythematosus?].

Annular erythema has been recognised as a cutaneous manifestation of Sjögren's syndrome in the Asian literature and has been assumed to represent a distinct clinical entity. Since there are common pathophysiologic mechanisms, mainly the presence of anti-Ro/SSA or anti-La/SSB antibodies, it is difficult to separate the annular erythema from subacute cutaneous lupus erythematosus. Histological examination may reveal dermal mucin deposition resembling lupus erythematosus tumidus. We present a Chinese patient with widespread annular erythema, keratoconjunctivitis sicca, and anti-Ro/SSA antibodies. Clinical, histopathological, and immunogenetic findings are discussed reviewing the current literature, and the differences between annular erythema associated with Sjögren's syndrome and cutaneous lupus erythematosus are emphasized.