Serum Level of Vitamin D and Autoantibodies Level in Systemic Lupus Erythematosus ( SLE ) Patients

Abstract

The involvement of vitamin D has been reported in immune response regulation, especially to inhibit B cell differentiation and activation. The objective of our study was to determine the association between serum vitamin D level with the concentration of anti-dsDNA, anti-Sm, IgG-IgM anti-cardiolipin and anti-vitamin D antibodies in SLE patients in Dr Saiful Anwar Hospital, Malang. Our subjects were fifty four female SLE (ACR 1992 revised criteria) out patients recruited from the Rheumato-Immunology Division, Dr Saiful Anwar Hospital, Malang, from January-June 2011. The mean age of the patients was 31.12 years (12-55 yo), duration of illness was 18,4 months (2-54 mo). ELISA method was used to assesessed serum vitamin D [25(OH)D3] level, anti-dsDNA, anti-Sm, IgG IgM ACA and anti-vitamin D antibodies. Correlation of serum vitamin D and autoantibodies level were analyzed using Pearson correlation test. Our study showed that 70.63 % of SLE patients had low vitamin D serum level ( < 30 ng/mL). We found the frequency of the positive antibodies as follow: anti-dsDNA in 70.30%, anti Sm in 35.55%, anti IgG ACA in 21.15%, anti IgM ACA in 25% and anti vitamin D in 64.81%. Serum level of 25(OH)D3 was negatively correlated to the level of anti-dsDNA and anti-vitamin D antibodies (r: 0.416, p: 0.032 and r:0.537, p: 0.041 respectively). There was no correlation between serum level of vitamin D with ACA and anti Sm antibodies. The low level of vitamin D in patients with SLE was related to anti-dsDNA and anti-vitamin D antibodies production . The low level of serum vitamin D in patients with SLE may be caused by the presence of anti vitamin D antibody.