Clinical Correlations of AntinuclearAutoantibodies in Scleroderma

Overview

Clinical correlations of antinuclear antibodies (ANA) were studied in a group of 69 patients (7 men)with systemic sclerosis (SSc) or sclerodermic overlap syndrome (SOS) and undifferentiated connec-tive tissue disease (UCTD) as well as in a group of 23 patients (6 men) with morphea. Detection ofANA was performed by indirect immunofluorescence on HEp-2 cells (IF) and by immunoblotting onnuclear extracts from HeLa cells (IB). ANA were present in 98% of patients with SSc and 100% withSOS. Anticentromere antibodies (ACA) were found in 4% of SSc patients (strict criteria), in 10% ofSSc patients when less strict criteria were applied, and in 11% of all patients with systemicinvolvement. Anti-Scl-70 antibodies were present in 73% of SSc patients and in 63% of all patientswith the systemic form. Neither of the two antibodies showed any clinical correlation. Otherantibodies were detected by IB (anti: SSA/Ro, SSB/La, fibrilarin, RA33, Jo-1, PM-Scl and nRNP)which showed some tendency of association with organ involvement. The low frequency of ACA andthe high frequency of anti-Scl-70 could be a selection bias of patients to referral center. However noclinical correlations were observed, suggesting demographic differences between sclerodermapatients. In morphea, ANA were present in 69% (IF) and in 60% (IB). The latter were of unknownspecificity with the exception of one ACA positive patient with suspected transition to SSc.

Key words:
systemic sclerosis, morphea, antinuclear antibodies, anticentromere, anti-Scl-70