Summary
Background. To describe three cases of myositis and review the scientific literature on the etiology, diagnosis and treatment of this disease.
Materials and Methods. Three clinical cases are presented in the article. A literature search was conducted using the PubMed and Scopus databases. Based on keywords and inclusion/exclusion criteria, 18 publications were selected for review.
Results. Case I. An 11-year-old boy presented with severe thigh and calf myalgia and inability to walk. Laboratory tests revealed a high creatine kinase level (13,598 U/L). He was diagnosed with recurrent myositis caused by influenza. Treatment with intravenous fluids and diclofenac was started. Following the treatment, creatine kinase levels decreased, and symptoms resolved and the patient was discharged.
Case II. An 8-year-old boy presented with leg pain and inability to walk. He had a 3-day history of flu-like symptoms. Elevated creatine kinase levels (4,032 U/L) were found, and a diagnosis of infection- induced myositis was made. He was treated with intravenous fluid therapy and diclofenac. The patient was discharged on the fourth day of illness with resoluted symptoms and decreasing creatine kinase levels.
Case III. A 7-year-old boy was referred due to back and leg pain, subfebrile fever, cough and proteinuria and haematuria in urine analysis. A markedly elevated creatine kinase level (21,782 U/L) was observed. The patient was hospitalized and received intravenous fluids and diclofenac. Methylprednisolone pulse therapy was initiated because of persistent proteinuria, haematuria and rising creatine kinase levels. On the seventh day, the patient was discharged with improving lab results and resolution of symptoms.
Conclusions. Benign acute childhood myositis is a rare condition, most often occurring after viral infections. It can cause significant concern for patients and parents but generally has a favourable prognosis. It is crucial for physicians to recognize this condition and distinguish it from other diseases with similar symptoms to avoid unnecessary diagnostic procedures.
