[The levels and clinical significance of serum B cell activating factor in Chinese patients with polymyositis or dermatomyositis].
OBJECTIVE
To investigate serum levels of B cell activating factor (BAFF) in Chinese patients with polymyositis (PM) or dermatomyositis (DM), and analyze the correlation of BAFF with autoantibodies and clinical phenotypes.


METHODS
Serum BAFF levels of 28 PM patients and 30 DM patients (study group), and 25 matched healthy controls (control group) were measured by ELISA. Serum anti-Jo-1 antibody levels were also measured by ELISA in all the subjects. The results of the two groups were compared by unpaired t test and the relevance was analyzed by Pearson's correlation analysis.


RESULTS
Serum levels of BAFF in PM/DM patients were significantly higher compared to healthy controls (P = 0.000), but there was no statistically significant difference between the PM and DM patients (P > 0.05). Patients with interstitial lung disease (ILD) had significantly higher serum BAFF level than the patients without ILD (P = 0.000) or the controls (P = 0.000). Serum BAFF levels of patients with positive anti-nuclear antibody (ANA) were significantly higher than those with negative ANA (P = 0.003). For patients with anti-Jo-1 antibodies, the serum BAFF levels were correlated with the serum concentration of anti-Jo-1 antibodies (r = 0.799, P = 0.006).


CONCLUSIONS
Serum levels of BAFF are increased in Chinese PM/DM patients. These findings indicate that BAFF may be possibly enrolled in the pathogenesis of PM/DM. Detecting serum BAFF levels could have some implication for the diagnosis and treatment of PM/DM.
Department of Rheumatology and Immunology, China-Japan Friendship Hospital, Beijing 100029, China.
Qing-lin
QL
Peng
Yao
Y
Xie
Rong-fu
RF
Zhang
Xiao-ming
XM
Shu
Guo-chun
GC
Wang
D000293:Adolescent; D000328:Adult; D000368:Aged; D053264:B-Cell Activating Factor / Q000097:blood*; D016022:Case-Control Studies; D003882:Dermatomyositis / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017285:Polymyositis / Q000097:blood*; D055815:Young Adult
D053264:B-Cell Activating Factor