To describe the rate and risk factors of deep neck space involvement of Kawasaki disease.

We performed a retrospective analysis using the Kids' Inpatient Database from 2006, 2009, 2012, and 2016. Kawasaki disease and deep neck space involvement cases were identified using International Classification of Diseases codes among children aged <12 years. Demographic and outcome data of Kawasaki disease cases with and without deep neck space involvement were compared.

Of 20 787 patients with Kawasaki disease, 0.6% (130 cases) had deep neck space involvement. On multivariable analysis, children aged ≥4 years (OR 8.41; 95% CI 3.79-18.7 in those aged 6-11 years), Asian or Pacific Islanders (OR 3.72; 95% CI 1.90-7.27), non-Hispanic black children (OR 2.39; 95% CI 1.34-4.28), and Northeast hospital region (OR 2.32; 95% CI 1.21-4.46) were associated with deep neck space involvement. Surgical drainage was performed in 21.7% of patients with deep neck space involvement. Deep neck space involvement was associated with longer hospital stay and greater costs.

Approximately 0.6% of patients with Kawasaki disease present with deep neck space involvement in the US. Deep neck space involvement of Kawasaki disease occurs primarily in older (≥4 years old), non-white, non-Hispanic children. Deep neck space involvement is associated with operative procedures for presumed abscess, longer hospital stay, and greater costs. In caring for children with suspected deep neck space abscess, particularly when they are not responding to antibiotics, clinicians should evaluate them for the possibility of Kawasaki disease.