Severe epidemic myalgia with an elevated level of serum interleukin-6 caused by human parechovirus type 3: a case report and brief review of the literature

Human parechovirus type 3 (HPeV-3) is known to cause cold-like symptoms, diarrhea, or severe infections such as sepsis in infants and children. In adults, HPeV-3 infection is rarely diagnosed because the symptoms are generally mild and self-limiting; however, this infection has been linked to epidemic myalgia, regardless of the presence of underlying diseases, immunosuppression, or sex. We describe an adult case of severe systemic myalgia and orchiodynia after infection with HPeV-3, which was transmitted from the child of the patient. Interleukin-6 (IL-6) level was found to be elevated in the patient's serum. Severe myalgia associated with HPeV-3 infection is potentially caused by an elevated serum level of IL-6.