[Juvenile dermatomyositis: Early onset and unusual presentation]

Area of Science:

• Pediatric Rheumatology
• Rare Diseases
• Dermatology

Background:

• Juvenile dermatomyositis (JDM) is a rare autoimmune disease affecting children, typically with onset around age seven.
• This report focuses on an exceptionally early-onset case in a 13-month-old infant.

Observation:

• The infant presented with unusual labial edema, periorbital edema, purpuric lesions, and aphthoid ulcerations.
• Severe muscle involvement included elevated muscle enzymes, myogenic electromyogram findings, axial hypotonia, and hypertrophic cardiomyopathy.

Findings:

• Diagnosis of JDM was confirmed based on clinical presentation, muscle enzyme levels, and electromyography.
• The patient exhibited severe manifestations including hypertrophic cardiomyopathy and axial hypotonia.

Implications:

• This case underscores the possibility of JDM onset in infancy with atypical cutaneous signs and severe systemic involvement.
• Early and aggressive treatment, including corticosteroids, methotrexate, and cyclophosphamide, led to significant clinical improvement.
• Prompt therapeutic intervention is crucial for improving outcomes in severe, early-onset JDM cases.