Elderly-onset Still's Disease Complicated by Macrophage Activation Syndrome: A Case Report and Review of the Literature.

Adult-onset Still's disease (AOSD) usually affects young adults. Some cases of elderly-onset Still's disease (EOSD) have been reported, but its clinical features are unclear. We herein report a 74-year-old woman who developed AOSD with macrophage activation syndrome (MAS). We also reviewed 24 previous EOSD cases in patients over 70 years old and compared the findings with overall AOSD. While the clinical features were similar between the two, including the presence of MAS, disseminated intravascular coagulation was more frequent in EOSD than in AOSD. Furthermore, despite a similar frequency of glucocorticoid use, immunosuppressants and biologics were less frequently administered in EOSD than in AOSD. This report highlights the fact that typical AOSD can develop in elderly patients with some characteristic features.