Objective: To evaluate immunological safety and immunogenicity of influenza vaccine administration in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA).
Patients and methods: Twenty-four patients with low and/or stable disease activity 14 with SLE (mean age 43.42+/-12.18 years; 13 women) and 10 with RA (mean age 51+/-14.57 years; 9 women), diagnosed on the basis of the American College of Rheumatology criteria, have been immunized with trivalent split influenza vaccine without adjuvant. Further 24 non-vaccinated patients, 14 with SLE and 10 with RA, and 10 vaccinated healthy subjects, all age- and sex-matched, were used as controls. The patients underwent clinical and laboratory (specific anti-influenzavirus antibodies, auto-antibodies, peripheral blood lymphocyte subpopulations) evaluation before and 30 days after vaccination; auto-antibodies were also assessed at 90 days and disease activity at 90 and 180 days.
Results: The specific antibody response towards the three used antigens (A/New Caledonia/20/99, A/Moscow/10/99, and B/Shangdong/7/97) significantly increased in both patients and healthy controls, without any significant difference between them. No significant difference could instead be observed on the clinical activity, auto-antibodies, and peripheral blood lymphocyte subpopulations before and after vaccination, and between patients and controls.
Conclusions: Trivalent split influenza vaccine without adjuvant seems to be safe and immunogenic in patients with SLE and RA, provided that only patients with low and/or stable disease activity are selected.