Prevalence of anti-histone antibodies, their clinical significance and correlation with other autoantibodies in a cohort of Italian scleroderma patients.

Purpose: The aim of our study was to determine the prevalence, clinical significance of antibodies to individual histone components and to evaluate their correlation with other autoantibody specificities in a cohort of Italian SSc patients. Some authors, demonstrated high prevalence of anti-histone antibodies in Italian SSc patients, associated with cardiac and renal involvement, suggesting a prognostic value of these autoantibodies; however, these data need to be confirmed.

Methods: Serum from 112 adult SSc patients, classified as diffuse (dc) and limited cutaneous (lc) SSc subsets were analyzed for autoantibodies by indirect immunofluorescence, fluoroenzyme immunoassay and enzyme immunoassay.

Results: AHA were found in 13 patients (11.6%), nine with lcSSc and four with dcSSc. Among them, five patients were anti-Scl70+ and four were anti-CENP B+. The presence of AHA was not associated with multi-organ involvement or with diffuse subset, as already described. Anti-Scl70 was detected in 43% of patients, anti-CENP B in 32% and anti-RNA polymerase III in 7.1%. We confirmed the association between anti-Scl70 antibodies and pulmonary fibrosis (OR 15.75, p < 0.0001).

Conclusion: In our experience, the very low prevalence of AHA in Italian SSc patients and the lack of association with clinical manifestations suggest that this test is of little clinical use; however, it would be worthwhile extending the study to a larger population of patients.