Adult onset Still's disease (AOSD) is an inflammatory disorder with elevated serum acute phase proteins. Interleukin-6 is a major contributor to the acute phase response. We therefore examined the serum levels of CRP, SAA and interleukin-6 in active and inactive AOSD.
Active patients had significantly elevated CRP, SAA, and interleukin-6 values. After steroid treatment a marked reduction was observed in all three parameters. There was a close kinetics on the fluctuations of CRP and SAA, but not on IL-6.
Acute phase proteins and IL-6 are useful markers of disease activity in AOSD.