Neurologic manifestations in Kawasaki disease and their clinical implications: a Korean nationwide pediatric cohort study

BACKGROUND: Neurological involvement in Kawasaki disease (KD) is rare and ranges from mild to severe, occasionally leading to fatal outcomes and poor prognosis. However, its impact on clinical outcomes, particularly coronary artery involvement, remains unclear. This study aimed to investigate neurological manifestations during the acute phase of KD and evaluate their clinical implications, focusing on treatment resistance and coronary complications. METHODS: We analyzed data from the Health Insurance Review and Assessment Service of the Republic of Korea between 2007 and 2022 for patients under 18 years of age diagnosed with KD (ICD-10 code M30.3). Neurological manifestations, ranging from mild and nonspecific symptoms to severe complications, were evaluated. RESULTS: Among 95,648 patients with KD, neurological manifestations occurred in 4319 (4.51 %), comprising 4540 events. The most common symptoms were febrile seizures (2.40 %), followed by meningitis/aseptic meningitis, headache, seizures, epilepsy, meningoencephalitis, irritability, brain hemorrhage, facial nerve palsy, and cerebral infarction or stroke. There were no significant differences in age or sex distribution between those with and without neurological manifestations, although prevalence was highest in patients >5 years. Neurological manifestations were more frequent in summer and were associated with longer hospital stays (p < 0.001), more frequent use of multiple intravenous immunoglobulin (IVIG) treatments (p < 0.001), and higher transfer and mortality rates (p < 0.001). However, no significant differences were observed in coronary interventions or adjunctive therapy use (aspirin, warfarin, steroids, and infliximab). CONCLUSIONS: Neurological manifestations in KD were associated with more frequent IVIG resistance, but showed no significant association with coronary outcomes.