Juvenile Dermatomyositis Triggered by Influenza B: A Case Report on Viral-Induced Autoimmunity

A previously healthy 13-year-old boy developed juvenile dermatomyositis (JDM) shortly after a confirmed influenza B infection, presenting with progressive proximal muscle weakness and classic cutaneous findings. Laboratory tests revealed elevated muscle enzymes and myositis-specific autoantibodies, supporting the diagnosis. The temporal association suggests a potential post-viral autoimmune trigger, highlighting influenza B as a possible environmental factor in JDM pathogenesis. This case reinforces the need for heightened clinical awareness and further research into virus-associated autoimmune mechanisms in pediatric myopathies.