In this prospective study of 14 children with KD (seven without and seven with CALs in the acute phase), we obtained patient measurements of a series of serum IL-18 levels in the acute, subacute, and convalescent phases. Serum IL-18 levels were measured with a Bio-Plex cytokine assay. Control samples were obtained from 18 febrile children with viral infection.
Compared with febrile controls, patients with acute-stage CALs [postintravenous immunoglobulin (post-IVIG) period] had a significantly higher IL-18 level (88.4?¡À?20.7 vs 56.0?¡À?35.0?pg/mL, p?=?0.006). However, those without acute-stage CALs (post-IVIG period) lacked similarly elevated IL-18 level readings (62.0?¡À?40.6 vs 56.0?¡À?35.0?pg/mL, p?=?0.762). The IL-18 level of patients with acute-stage CALs did not decrease significantly until the convalescent phase (97.4?¡À?55.8 vs 38.7?¡À?22.6?pg/mL, p?=?0.018), but for those without CALs, it decreased significantly in the subacute phase (60.2?¡À?37.4 vs 23.6?¡À?13.8?pg/mL, p?=?0.018). In the subacute stage, there was a significant difference of IL-18 level between patients with and without acute-stage CALs (p?=?0.048).
Our data show that IL-18 levels were elevated in the acute phase of KD and might be related to the formation of CALs.