Objective: To determine the prevalence and clinical significance of antihistone antibodies (AHA) in systemic sclerosis (SSc).
Methods: Serum samples from patients with limited cutaneous SSc (n = 44), diffuse cutaneous SSc (dcSSc; n = 48), and other SSc-related disorders (n = 22) were examined by enzyme-linked immunosorbent assay and immunoblotting for AHA.
Results: AHA were demonstrated in 29% of the 92 SSc patients and in 44% of those with dcSSc. The presence of AHA correlated with severe pulmonary fibrosis in those with dcSSc. Immunoblotting revealed that the predominant antigen was histone H1.
Conclusion: AHA might be a serologic indicator of the severity of pulmonary fibrosis in SSc.