This article presents the findings of a nationwide population-based study in Taiwan on the epidemiology and risk factors for cytomegalovirus (CMV) disease in autoimmune inflammatory rheumatic diseases (AIIRDs). The study used Taiwan's National Health Insurance Research Database to identify patients with AIIRDs and matched control subjects. The results showed that patients with AIIRDs had a higher rate of CMV disease compared to the control group, with patients with dermatomyositis/polymyositis (DM/PM) exhibiting the highest risk. Comorbidities and certain medications, such as mycophenolate, cyclophosphamide, and cyclosporin, were associated with an increased risk of CMV disease. The study highlights the importance of early detection and differentiation of CMV disease in patients with AIIRDs. [Extracted from the article]