Viral Myositis Secondary to Influenza A in a Preschool Child in Saudi Arabia: A Case Report

Infective myositis is a rare complication of viral infection, occurring most commonly in children. Here, we present the first case report in Saudi Arabia that describes a four-year-old healthy female who presented to the emergency department with a history of fever associated with coryzal symptoms for four days and a one-day history of bilateral lower limb pain and an inability to walk without assistance. Lower limb pain was not associated with joint pain, swelling, or skin rashes. The respiratory virus panel was positive for influenza A, and she was found to have increased levels of creatine kinase (CK). The patient was diagnosed with viral myositis secondary to influenza type A infection and was admitted for dehydration. She was treated successfully with supportive measures and oseltamivir. The patient's condition improved three days after the initial presentation and was discharged and followed up to ensure resolution. Extensive laboratory assessment and hospitalization can often be deemed unnecessary, given that the majority of cases of viral myositis carry a positive prognosis and are self-limiting. Therefore, it is important to consider viral myositis as a potential diagnosis for a child presenting with difficulties walking, particularly if these symptoms arise following a respiratory infection.