Paediatric Rheumatology
Association of NXP2 autoantibodies with a more severe clinical phenotype of juvenile dermatomyositis
Y. Wang1, J. Liang2, J. Wang3, F. Zheng4, L. Teng5, Q. Ma6, Y. Zhou7, L. Liang8, J. Lin9, M. Lu10, H. Cao11, X. Xu12
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China.
- Department of Rheumatology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China. meipinglu@zju.edu.cn
- Department of Rheumatology, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China. caohengzju@zju.edu.cn
- Department of Rheumatology Immunology and Allergy, Children’s Hospital, Zhejiang University School of Medicine, National Clinical Research Center for Child Health, Hangzhou, China. xuxuefeng@zju.edu.cn
CER18814
Paediatric Rheumatology
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PMID: 41537529 [PubMed]
Received: 09/04/2025
Accepted : 30/10/2025
In Press: 13/01/2026
Abstract
OBJECTIVES:
Myositis specific autoantibodies (MSAs) correlate with a distinct clinical phenotype of juvenile dermatomyositis (JDM). This study aims to compare the clinical features of JDM patients with positive anti-NXP2, anti-MDA5 and anti-TIF1γ autoantibodies, and differences in juvenile (JDM) and adult dermatomyositis.
METHODS:
This study included 18 NXP2+ JDM patients, 12 MDA5+ JDM patients, 12 TIF1γ+ JDM patients, and 20 NXP2+ adult DM patients. Repeated measures analysis was performed to track longitudinal changes in creatine kinase (CK) levels, Childhood Myositis Assessment Scale (CMAS) scores, and IL-10/γ-interferon ratios. Kaplan-Meier survival and Cox regression analysed relapse rates and recurrence factors.
RESULTS:
NXP2+ JDM patients exhibited significantly elevated serum creatine kinase levels compared to MDA5+ JDM (3792 vs. 180; p<0.001), adult NXP2+DM (3792 vs. 437.5; p=0.003), and TIF1-γ+ JDM (3792 vs. 189; p<0.001). Concurrently, NXP2+ JDM patients also showed lower CMAS scores compared to MDA5+ (31.33 vs. 43.25; p<0.001) and TIF1-γ+ JDM groups (31.33 vs. 42.67; p=0.004). The NXP2+ JDM patients presented with a high frequency of macrophage activation syndrome (MAS), myocardial damage, dysphagia, and calcinosis. Repeated measures analysis showed that NXP2+ JDM patients had more severe muscle damage throughout the disease course compared with MDA5+ JDM patients and TIF1γ+ JDM patients. Furthermore, significant interaction effects of Group and Time on CK were observed in JDM patients. A three-year follow-up study revealed a higher relapse risk in NXP2+ JDM patients compared to MDA5+ JDM, TIF1γ+ JDM and NXP2+ adult DM patients.
CONCLUSIONS:
The NXP2+ JDM patients experience more severe muscle damage, systemic complications, and higher relapse risks. Monitoring dynamic changes in CK and CMAS is essential for predicting disease progression and relapse risk.
