Epstein-Barr virus infection associated polymyositis and coronary artery dilation

BACKGROUND: Epstein-Barr virus (EBV) infects more than 90% of the population worldwide. However, chronic active EBV infection (CAEBV) is one of the EBV-positive T- or NK-lymphoproliferative diseases with high morbidity and mortality. Here, we report a case of a 9-year girl with CAEBV, successively presenting with polymyositis and coronary artery dilation (CAD). CASE PRESENTATION: The girl complained of fatigue for more than 1 month. Muscle strength examinations had no abnormal findings. Blood chemistries showed elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatine kinase (CK). Magnetic resonance imaging (MRI) showed spotty high-intensity signals in thigh muscles, and electromyogram suggested myogenic damage. The significant findings were positive EBV antibodies (EBVEA-IgG, EBVCA-IgG, and EBVNA-IgG), increased EBV DNA copies in B, T, and NK cells, and positive EBV-encoded small RNA in biopsy muscle specimen. The girl received ganciclovir, intravenous immunoglobulin, and methylprednisolone, and her symptoms improved. On the 45th day of hospitalization, echocardiograph revealed CAD. She received additional anticoagulants and Tocilizumab. Her condition improved and continued to be followed up at the clinic preparing for hematopoietic stem cell transplantation. CONCLUSIONS: This is the first reported case of CAEBV successively with polymyositis and CAD. This case makes the diagnoses of autoimmune diseases in children more complicated. Careful investigation of hidden CAEBV should be recommended in children with atypical polymyositis or CAD.