Objective  To explore the clinical characteristics of patients with connective tissue disease with positive anti-small ubiquitin-like modifier activating enzyme (SAE) antibodies. Methods Retrospectively select the patients who completed the screening of myositis autoantibodies in West China Hospital of Sichuan University between January 1, 2015 and May 30, 2021. Meanwhile, patients with positive anti-SAE antibodies were screened out. According to the clinical data of anti-SAE antibodies positive patients, they were divided into the following groups: tumor group and non-tumor group, ILD group and non-ILD group, inflammatory myopathy group and non-inflammatory myopathy group. Clinical symptoms, signs, laboratory examinations, imaging examinations and other clinical data of the above patients were collected. Results  A total of 1 594 patients were screened for myositis autoantibodies, of which 56 were positive for anti-SAE antibodies, with a positive rate of 3.5%. In 56 patients, 32.1% in skin involvement, 35.7% in muscle involvement, 12.5% in joint involvement, 5.4% in dysphagia, 5.4% in weight loss, 58.9% in patients with interstitial lung disease (ILD) and 12.5% in patients with tumor history. There was no significant difference in age, sex, skin involvement, muscle involvement, joint involvement and respiratory system involvement between the tumor group and the non-tumor group (P>0.05). Except for age, the frequency of muscle involvement, and positive rate of anti-Ro-52 antibody, there was no significant difference in other indicators between the ILD group and the non-ILD group (P>0.05). Except for the positive rate of ILD, the frequency of skin involvement, the frequency of muscle involvement, the level of creatine kinase and hydroxybutyrate dehydrogenase (P<0.05), there was no significant difference in other indexes between the non-inflammatory myopathy group and the inflammatory myopathy group (P>0.05). Conclusions  The patients with positive anti-SAE antibodies mainly present skin and muscle symptoms, and are prone to ILD, malignant tumor and dysphagia. Patients with positive anti-SAE antibodies and ILD were older, had less muscle damage, and had a higher positive rate of anti-Ro-52 antibody. Anti-SAE antibodies appear not only in patients with inflammatory myopathy, but also in non-inflammatory myopathy, often associated with a higher frequency of ILD and less muscle involvement.

Citation： LUO Zhongling, CUI Beibei, XIE Qibing, YIN Geng. Clinical features of patients with connective tissue disease positive for anti-small ubiquitin-like modifier activating enzyme antibodies. West China Medical Journal, 2023, 38(1): 45-50. doi: 10.7507/1002-0179.202207133 Copy