Abstract: ZHUANG Jie-qiu*, CHEN Fang-xuan, JIN Wan-wan, YANG Qing, GAO Yu. *Department of Paediatric Nephrology, Yuying Children′s Hospital and Second Affiliated Hospital of Wenzhou Medical College, Wenzhou 325027, Zhejiang, China Corresponding author: GAO Yu, Email: gaoyu@medmail.com.cn 【Abstract】 Objective To assess the associations of anti-Smith antibodies with clinical manifestations and disease activity in children with systemic lupus erythematosus （SLE）. Methods According to SLE disease activity index （SLEDAI） score, 72 children with SLE were divided into the active group and inactive group. An immunoblotting method was used to detect serum anti-Smith antibodies in these subjects. Chi-square test was conducted to assess the associations of anti-Smith antibodies with clinical manifestations and disease activity in these patients. Results Of these patients, 28 （38.9%） were assigned into the inactive group, and 44 （61.1%） to the active group. Anti-Smith antibodies were detected in 17 （23.6%） patients, but not in the other 55 （76.4%） patients. Elevated incidence rate of kidney injury was observed in anti-Smith antibody-positive patients compared with anti-Smith antibody-negative patients （70.6% （12/17） vs. 41.8% （23/55）, P < 0.05）. Meanwhile, the positivity rate of anti-Smith antibodies was 31.8% （14/44） in the active group, significantly higher than that in the inactive group （10.7%, 3/28, P < 0.05）. Conclusions Anti-Smith antibodies are not only an important indicator for the diagnosis of SLE, but also a risk factor for disease exacerbation and kidney injury in children with SLE.

Key words: Anti-Smith antibody