Introduction.
Immunological factors seem to play a pivotal role in
Adult Onset Still's Disease (AOSD). Among all,
IL-18 cytokine is overexpressed and drives the inflammatory process. Objective. We aimed to investigate the levels of
IL-18 in sera of Italian patients with AOSD and to assess its possible role as a marker of disease activity. Methods.
IL-18 serum levels were determined by ELISA in 26 Italian patients with AOSD. Disease activity was assessed using Pouchot's criteria. As controls, 21 patients with
Rheumatoid Arthritis (RA), 21 patients with
Sjogren's Syndrome (SS), 20 patients with
Systemic Lupus Erythematosus (SLE), and 21 healthy subjects (normal human sera, NHS) were evaluated. Results.
IL-18 serum levels were significantly higher in patients with active AOSD than in non-active (P = 0.001) and control groups (RA P = 0.0070, SS P = 0.0029, SLE P = 0.0032, NHS P = 0.0004). A significant correlation between
IL-18 serum levels and disease activity (P < 0.0001), and laboratory parameters as
ferritin (P = 0.0127) and
C-reactive protein (P = 0.0032) was demonstrated. Conclusions. Higher levels of
IL-18 are detected in active AODS patients and correlate with disease activity and inflammatory laboratory features. ROC-AUC analysis of the serum concentration of
IL-18 suggests that it can be considered a diagnostic marker of AOSD. This paper supports the targeting of this
cytokine as a possible therapeutic option in AOSD.