Objective. The role of the cytokine interleukin 15 (IL-15) in rheumatic dis
ease is unclear. We examined serum levels of IL-15 in patients with various
Methods. Serum levels of IL-15 were determined by sandwich ELISA.
Results. Serum levels of IL-15 were significantly increased in patients wit
h poly myositis/dermatomyositis, polyarteritis nodosa, and systemic scleros
is; and significantly increased as well in disease complicated by interstit
ial pneumonitis (IP). hemophagocytic syndrome (HPS), and/or vasculitis. Pat
ients with serum IL-15 levels less than or equal to 5 pg/ml showed signific
antly high rates of survival.
Conclusion. IL-15 is related to the pathogenesis of IP, HPS, and/or vasculi
tis. Serum IL-15 level could possibly be used as a marker of prognosis.