Thyroid and non organ specific autoantibodies in patients with thyroid-associated ophthalmopathy: Immune modulation by intravenous immunoglobulin

Abstract

The aim of this study was to evaluate the dynamics of circulating autoantibodies in patients with thyroid associated ophthalmopathy (TAO) treated with IVIG.The authors evaluate the variations of antithyroid and non-organ specific autoantibodies in nine patients with euthyroid Graves' ophthalmopathy (eGO) treated with IVIG and not treated with antithyroid drugs or immunosuppressive agents. Furthermore they studied the variations of non organ specific autoantibodies in 53 patients with Graves' disease and ophthalmopathy (GO) treated with IVIG and with antithyroid drugs but not with other immunosuppressive agents, in comparison with a control group of ten healthy subjects. Autoantibody evaluations were performed immediately before the start of IVIG and were repeated at the end of the treatment and six months-one year after the stop (last control) of IVIG.Among nine patients with eGO two presented positive antithyroglobulin antibodies and in both the authors saw a negativization of the titer at the end and after the treatment. Anti-microsomal antibodies were present in seven patients (78%) and in four cases (57%) they were reduced or negative at the end of therapy. Thyroid stimulating antibodies were present in three patients and in all the negativization at the end and after the treatment was seen. Antinuclear antibodies (ANA) were present in one patient and became negative at the end of the treatment. Among 53 patients with GO ten were positive for ANA before the treatment and nine of the positive became negative at the end of the treatment. Two of these last became positive again at the last control. Among the 43 patients initially negative for ANA, three became positive at the end of the treatment and another three at the last control. Among 39 patients with GO, eight were positive for anti-smooth muscle antibodies (ASMA) before the treatment and seven of the positive became negative at the end of the treatment. No one of these last became positive again at the last control. Among the 31 patients initially negative for ASMA, two became positive at the end of the treatment, and another one at the last control. No one of the ten healthy control subjects presented ANA or ASMA positivity before and after one year of follow-up.In conclusion, a high prevalence of non organ specific autoantibodies (ANA and ASMA) has been observed in patients affected with GO. Furthermore, the follow-up of this group of patients has shown the appearance of new cases of ANA and ASMA positive patients with GO. IVIG seems to immune-modulate antithyroid antibodies and non organ specific autoantibodies in patients with TAO.