Resistance to intravenous immunoglobulin in children with Kawasaki disease

Objectives To explore the increased incidence of intravenous immunoglobulin- (IVIG) resistance among San Diego County patients with Kawasaki disease (KD) in 2006 and to evaluate a scoring system to predict IVIG-resistant patients with KD. Study design We performed a retrospective review of patients with KD treated within 10 days of fever onset. With multivariate analysis, independent predictors of IVIG-resistance were combined into a scoring system. Results In 2006, 38.3% of patients with KD in San Diego County were IVIG-resistant, a significant increase over previous years. IVIG-resistance was not associated with a particular brand or lot of IVIG. Resistant patients were diagnosed earlier, had higher percent bands, and higher concentrations of C-reactive protein, alanine aminotransferase, and gamma-glutamyl transferase. They also had lower platelet counts and age-adjusted hemoglobin concentrations and were more likely to have aneurysms (P =.0008). A scoring system developed to predict IVIG-resistant patients using illness day, percent bands, gamma-glutamyl transferase, and age-adjusted hemoglobin had a sensitivity of 73.3% and specificity of 61.9%. Conclusions An unexplained increase in IVIG-resistance was noted among patients with KD in San Diego County in 2006. Scoring systems based on demographic and laboratory data were insufficiently accurate to be clinically useful in our ethnically diverse population.