An 81-year-old Japanese man with a medical history of diabetes mellitus and hypertension was diagnosed with the novel coronavirus disease 2019 (COVID-19). The patient developed pain in the bilateral shoulders and hips 3 days after the disease onset and presented to our outpatient clinic after 1 month. Referring to diagnostic criteria, we diagnosed him with polymyalgia rheumatica (PMR). We initiated prednisolone at 15 mg per day and his symptoms improved immediately. The clinical course of the patient indicated that the SARS-CoV-2 infection triggered the onset of autoimmune disease, PMR in this case.
Keywords: COVID-19; SARS-CoV-2; autoimmune diseases; human leukocyte antigen; polymyalgia rheumatica.