The serum ferritin level is high in patients with SD, with values of 2,500 to 10,000 or even higher in 70% of patients reported. These high levels most probably reflect an acute phase response, since hepatocytes responding to inflammatory cytokines increase ferritin synthesis [5] . Since ferritin levels are not that high in other rheumatologic diseases, it was suggested as a candidate for a serologic marker for the diagnosis and monitoring of the response to treatment of SD. However, other studies suggest that the portion of glycosylated ferritin (less than 20% of the total value of ferritin) is a more specific finding for the diagnosis of SD, in contrast to other rheumatologic diseases where the value is much higher [6] . Interleukin-6, TNF alpha, interferon gamma and interleukin 18 may be elevated during the active phase of the disease, but serology for antinuclear antibody and rheumatoid factor are negative [7] .