What laboratory finding is typically elevated in a patient with adult-onset Still's disease?

In adult-onset Still's disease, a systemic inflammatory condition characterized by fever, rash, and arthritis, elevated ferritin levels are a significant laboratory finding. Ferritin serves as an acute-phase reactant, and in the context of Still's disease, it reflects the underlying inflammatory process and increased macrophage activity.

The pathophysiology of adult-onset Still's disease involves dysregulation of the immune system, leading to excessive production of pro-inflammatory cytokines such as interleukin-6 (IL-6). This results in increased ferritin synthesis, elevated serum levels, and also contributes to the anemia of chronic disease. Hence, high ferritin is consistent with the active inflammatory response these patients exhibit.

Monitoring ferritin levels can also help assess disease activity and the response to treatment in adult-onset Still's disease, making it a crucial marker in this context.