Interleukin-18 and coronary artery lesions in patients with Kawasaki disease

BACKGROUND: Interleukin-18 (IL-18) plays an important role in mediating cytokine cascade leading to coronary artery lesions (CALs) in Kawasaki disease (KD). However, our research suggested that the literature regarding IL-18 and KD is limited. Consequently, this study aimed to evaluate the correlation between IL-18 and CALs in patients with KD. METHODS: 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. RESULTS: Compared with febrile controls, patients with acute-stage CALs [postintravenous immunoglobulin (post-IVIG) period] had a significantly higher IL-18 level (88.4 ± 20.7 vs 56.0 ± 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 ± 40.6 vs 56.0 ± 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 ± 55.8 vs 38.7 ± 22.6 pg/mL, p = 0.018), but for those without CALs, it decreased significantly in the subacute phase (60.2 ± 37.4 vs 23.6 ± 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). CONCLUSION: Our data show that IL-18 levels were elevated in the acute phase of KD and might be related to the formation of CALs.