Age-Onset-Related Particularities of Pediatric MS-Understanding the Spectrum: A Tertiary Center Experience

Area of Science:

• Neurology
• Pediatric Neurology
• Neuroimmunology

Background:

• Pediatric-onset multiple sclerosis (POMS) is a rare, heterogeneous neurological condition.
• Clinical features, disease progression, and treatment responses in POMS significantly differ based on the patient's age at onset.
• Early-onset MS (under 10 years) presents unique diagnostic and management challenges due to atypical symptoms and heightened inflammatory activity.

Purpose of the Study:

• To investigate age-related clinical, radiological, and therapeutic characteristics of pediatric MS.
• To specifically analyze early-onset cases (<10 years) and compare them with intermediate (10-12 years) and late-onset (>12 years) forms of the disease.

Main Methods:

• Retrospective analysis of medical records from 120 pediatric patients with MS diagnosed between 2018 and 2024.
• Patients were stratified by age at onset: early (<10 years), intermediate (10-12 years), and late (>12 years).
• Assessment included clinical presentation, relapse frequency and timing, Expanded Disability Status Scale (EDSS) scores, MRI findings, and treatment patterns.

Main Results:

• Early-onset MS is linked to atypical symptoms, delayed diagnosis, increased relapse rates, and multifocal brainstem/cerebellar lesions.
• Diagnosis was significantly delayed in younger children compared to adolescents.
• While EDSS scores remained stable initially, early-onset patients experienced a decline after year four. High-efficacy therapies were underutilized due to age restrictions.
• Intermediate-onset patients showed mixed features and the best motor function preservation (EDSS 0) at follow-up.
• Younger patients exhibited more extensive and confluent MRI lesions, particularly within the first two years post-onset.

Conclusions:

• Age at onset is a critical factor influencing the clinical trajectory and treatment efficacy in pediatric MS.
• Early identification and prompt initiation of appropriate therapies, including high-efficacy agents, are crucial for mitigating long-term disability.
• Further multicenter research with standardized protocols for imaging and cognitive assessments is essential to refine care strategies for pediatric MS patients.