Juvenile dermatomyositis (JDM) is a rare autoimmune disease. It is a chronic condition in most kids, who often experience weakness, skin rash, and inflammation with relatively unpredictable disease course and treatment response. In this study, the researchers used mass spectrometry to analyze the protein contents of urine from kids with JDM, and compared them with samples from healthy controls. They found several differentially expressed proteins, including cathepsin D and galectin-3 binding protein. The levels of these two proteins were higher in the urine from kids with JDM. They also identified some proteins that correlate with clinical measures of disease activity and damage. For example, the levels of cathepsin D in urine positively correlated with disease damage and negatively correlated with results from a muscle disease activity assessment scale.

What is exciting about this article?

Results from this study suggest that urine analysis may help provide a better understanding of the changes associated with JDM at the protein level. The next step would be to validate the study’s results in larger cohorts. Further, this article shows that urine analysis can be a non-invasive way to study rare diseases such as JDM.

Grant support


Research Areas:

Autoimmunity Clinical Research Computational Biology Immunology Muscle Biology


Urine proteomics by mass spectrometry identifies proteins involved in key pathogenic pathways in patients with juvenile dermatomyositis.

Morales M, Alayi TD, Tawalbeh SM, Sydenstricker AV, Spathis R, Kim H, Nagaraju K, Hathout Y, Rider LG
Rheumatology (Oxford).
2023 Sep 1;
doi: 10.1093/rheumatology/kead033
PMID: 36661295

Research reported in this publication was supported by the Intramural Research Program of the NIHʼs National Institute of Arthritis and Musculoskeletal and Skin Diseases.