Antinuclear antibodies in rosacea patients

Introduction. Rosacea is a common, chronic, inflammatory disorder, characterized by facial flushing and a spectrum of skin changes including erythema, telangiectasia, burning, coarseness of skin and inflammatory papulopustular eruption resembling acne. Not all mechanisms of its development are known yet. The clinical similarity to other dermatoses, mainly to malar rash of systemic lupus erythematosus (SLE), might cause diagnostic problems, particularly in patients with elevated anti-nuclear antibody titres.
Objective. To assess the frequency, titre and specificity of antinuclear antibodies, and to evaluate their connection with age, sex and clinical subset of rosacea.
Material and methods. The study was performed in 86 patients (65 wo-men and 21 men) with rosacea and 24 sex- and age-matched controls. The indirect immunofluorescence test was performed on HEp-2 cells. Patients’ sera with ANA titres of 160 or higher were evaluated by Euroline assay (EUROIMMUN Medizinische Labordiagnostika AG, Lubeck, Germany) and repeated 6 months later.
Results. In the rosacea group, antinuclear antibodies in a titre greater than or equal to 160 were present in 48.84% of patients with rosacea. Within this group, 18.61% had a titre between 320 and 640. In 8.14% the titre was higher than 1280. Elevated ANA titres were found more often in women (50.7%) than in men (42.85%). The results of the Euroimmun assay were negative. No autoantibodies to nRNP, Sm, Ro-60, Ro-52, La, dsDNA, PM-Scl, Jo-1, histones or ribosomal P-protein were disclosed. After 6 months of observation the antibody titres were comparable and the reduction or increase in numerical values was within one dilution, which was within the limit of the error of the method. In a 2-year observation period we did not recognize an autoimmunological or neoplastic process in any patient.
Conclusions. The high frequency of ANA in the sera of patients with rosacea might be related to polyclonal activation of B lymphocytes. Low titres of ANAs have no diagnostic value. The presence of ANA, face erythema and photosensitivity in rosacea patients might lead to misdiagnosis and overdiagnosis of SLE