Useful predictors of Kawasaki disease without complications before initial acute-phase treatment

Kawasaki disease (KD) is an acute febrile systemic vasculitis that primarily affects children younger than 5 years, with coronary artery lesions (CALs) as its severe complications. Intravenous immunoglobulin (IVIG) therapy resistance has been implicated in CAL development, and its known predictors are as follows: Egami score, Kobayashi score, C-reactive protein (CRP), albumin, CRP-to-albumin ratio, and neutrophil-to-lymphocyte ratio (NLR). However, the most useful predictor for IVIG resistance in patients with KD without complications before initial acute-phase treatment remains unclear. Therefore, this study aimed to determine the most useful predictor for IVIG resistance in such patients. This retrospective study included data from 202 patients with KD who underwent acute-phase treatment from January 2009 to March 2021. Among 46 IVIG-resistant patients, 22 patients required rescue therapy (rescued patients), while the remaining 24 received no rescue therapy for resistance and had no CALs. Among the 6 indices, NLR had the highest sensitivity and specificity for the detection of all IVIG-resistant patients and rescued patients (0.724 and 0.728, respectively), and logistic regression analysis showed that the NLR was the sole independent predictor both for the IVIG-resistant patients and for the rescued patients (P < 0.001 and = 0.002, Odds ratio = 5.797 and 5.814, 95% confidence interval = 2.687–12.504 and 1.954–17.299, respectively). NLR was the useful predictor for all IVIG-resistant patients and rescued patients among those with KD without complications before initial acute-phase treatment.