Autoantibody profile and clinical patterns in 619 Italian patients with cutaneous lupus erythematosus

Background Anti-nuclear antibodies (ANA), anti-extractable nuclear antigens (ENA) and anti-dsDNA antibodies areoften associated with cutaneous lupus erythematosus (CLE), with variable frequency depending on skin subtype. However,specific data based on large case-series on the pathogenetic, diagnostic and prognostic meaning of such autoantibodiesare still lacking.Objective To characterize the correlations between CLE subtypes as well as LE-non-specific skin lesions and theirautoantibody pattern.Methods Epidemiological, clinical and immunopathological data of 619 Italian patients with CLE and LE-non-specific skinlesions were analysed. Differences in age, sex, clinical features and autoantibody profile were evaluated in each LE subgroup.Results Anti-nuclear antibodies (P < 0.0001), anti-dsDNA (P < 0.0001), ENA (P = 0.001), anti-Sm (P = 0.001), anti-RNP (P = 0.004) and anti-histone (P = 0.005) antibodies were associated with SLE. A strong association between ANA(P < 0.0001) and anti-dsDNA (P < 0.0001) and female gender was also found: positive ANA and positive anti-dsDNAhad a higher prevalence among females. Chronic CLE resulted to be negatively associated with ENA (OR = 0.51,P < 0.0001), anti-Ro/SSA (OR = 0.49, P < 0.0001) and anti-dsDNA (OR = 0.37, P < 0.0001). Intermittent CLE resultedto be negatively associated with ENA (OR = 0.50, P = 0.007) and ANA (OR = 0.61, P = 0.025). Subacute CLE resultedto be associated with ENA (OR = 5.19, P < 0.0001), anti-Ro/SSA (OR = 3.83, P < 0.0001), anti-Smith (OR = 2.95,P = 0.004) and anti-RNP (OR = 3.18, P = 0.007). Acute CLE resulted to be strongly associated with anti-dsDNA(OR = 6.0, P < 0.0001) and ANA (OR = 18.1, P < 0.0001). LE-non-specific skin lesions resulted to be significantly associatedwith systemic involvement. Livedo reticularis was significantly associated with ENA (P = 0.007) and anti-Ro/SSA(P = 0.036). Palpable purpura and periungual telangiectasia were significantly associated with ANA.Conclusion According to our findings, some well-known associations between CLE subtypes and autoantibody profilewere confirmed; moreover, specific association between autoantibodies and LE-non-specific skin lesions was highlighted.A strict association between anti-ENA and anti-Ro/SSA antibodies and livedo reticularis, ANA and palpable purpura,and ANA and periungual telangiectasia was evidenced.