Deforming Arthropathy of the Hands in Systemic Lupus Erythematosus is Associated with Antibodies to SSA/Ro and to SSB/La

Thirteen patients with systemic lupus erythematosus and deforming arthropathy (DA) of the hands were compared with 111 patients with SLE without deforming arthropathy. Clinical features were comparable in the two groups. Patients fulfilling criteria for mixed connective tissue disease (MCTD) were not included in the present study. A higher prevalence of antibodies to SSA/Ro (P < 0.0125) and SSB/La (P < 0.004) were found in the SLE-DA group. The detection of antibodies to SSA/Ro and SSB/La was even more strictly associated with DA in SLE antibodies to SSA/Ro alone (P < 0.002). Regarding the fine specificity of anti-SSA/Ro, a prevalent response to the 52 kD protein of the Ro antigen was found. We conclude that patients with SLE developing deformities of the hands belong to a subset of patients with circulating antibodies to SSA/Ro, particularly to the 52 kD component, and to SSB/La.