Exploring clinical features and therapeutic outcomes in Indian children with mixed connective tissue disease: A multicenter study.

Introduction: Mixed connective tissue disease (MCTD) is a rare entity in children. There is a paucity of studies on juvenile-onset MCTD (jMCTD) worldwide especially from Southeast Asia.

Objectives: To describe clinical and laboratory features of jMCTD diagnosed at pediatric rheumatology centers across India.

Methods: A predesigned detailed case proforma in an excel format was prepared and was sent to all the Pediatric Rheumatology centers in India. Eleven centers provided the clinical and laboratory data of their jMCTD patients, which was then compiled and analyzed in detail.

Results: Thirty-one jMCTD patients from 11 centers were included in the study. Our cohort had 27 females and four male patients over 12 months (August 2021 to July 2022). The median age at presentation was 12 years (range 5-18 years) and the median duration of symptoms was 24 months at diagnosis (range 2-96 months). The common features included arthritis (90%), malar rash (70.9%), and Raynaud's phenomenon (70.9%). At a mean follow-up of 43 months (range 1-168 months), 45% of them were in remission. There were two deaths reported, due to macrophage activation syndrome and sepsis respectively.

Conclusion: We present the largest multicenter experience on jMCTD from the Indian subcontinent. The study's findings serve as a crucial stepping stone toward unraveling the complexities of jMCTD and improving patient care and management strategies.