Association between post-intravenous immunoglobulin hypothermia and lower receipt of second-line therapy in Kawasaki disease: a single-center retrospective cohort study.

INTRODUCTION/

objectivesPost-IVIG temperature patterns may be associated with the subsequent treatment course in Kawasaki disease (KD), but evidence regarding outcomes among patients who develop hypothermia after treatment remains limited. We evaluated the association between hypothermia following IVIG therapy and the receipt of second-line treatment.

methodsWe retrospectively reviewed patients with KD admitted to Matsudo City General Hospital between January 2018 and December 2023. Patients who achieved defervescence (body temperature < 37.5 °C) within 48 h after IVIG administration were included. Hypothermia was defined as body temperature < 36.0 °C within 48 h after IVIG administration. The primary outcome was the receipt of second-line therapy. Sensitivity analyses were conducted using alternative hypothermia thresholds of 35.5 °C and 35.0 °C. At the 35.5 °C threshold, both univariable and multivariable logistic regression analyses were performed; at the 35.0 °C threshold, results were presented descriptively because regression estimates were not estimable owing to zero-event cells.

resultsOf 1063 patients screened, 557 met the inclusion criteria. Hypothermia occurred in 324 (58.2%) patients. Second-line therapy was required less frequently in the hypothermia group than in the non-hypothermia group (14.2% vs. 28.3%; adjusted odds ratio, 0.39; 95% confidence interval, 0.25-0.62). Findings were consistent using the 35.5 °C threshold. At the 35.0 °C threshold, none of the 7 patients with hypothermia received second-line therapy, precluding estimation of the odds ratio.

conclusionAmong patients with KD who achieved defervescence within 48 h after IVIG administration, second-line therapy was less frequently administered to those who developed post-IVIG hypothermia. Prospective studies are needed to clarify the clinical significance of this finding. Key Points • Among patients with Kawasaki disease who achieved defervescence within 48 h after IVIG administration, second-line therapy was less frequently administered to those who developed post-IVIG hypothermia (< 36.0 °C). • This association remained significant after adjustment for age, sex, Gunma score, and concomitant medications. • The clinical significance of post-IVIG temperature patterns requires further evaluation in prospective studies.