“…Elevated serum ferritin levels were evaluated in many cohorts [18,19,77,126,141,154,184,192,198,202,204] and case-control studies [20,58,61,73,98,217]. For instance, in one case-control study that included patients with fever of unknown origin, raised ferritin values > 5 times the upper level of normal were associated with a diagnosis of AOSD and with an odds ratio (OR) of 132.8 (95% CI 7.1-2502.9) [20].…”