Decreased hemoglobin after initial treatment is associated with treatment resistance in Kawasaki disease in Kobayashi risk stratification

Background Although Kawasaki disease (KD) is known to cause anemia, the relationship between its prognosis and hemoglobin level is less well known. Methods We herein performed a secondary analysis of data from a previous study (Post-RAISE). Children aged 6 months to 2 years at the time of KD diagnosis were enrolled. Decreased hemoglobin was defined as a decrease > 10% on post-treatment day 2 compared with the level prior to the initial therapy. Results Of 1253 KD cases, treatment resistance was observed in 209 (17%) and was significantly more frequent in the decreased hemoglobin group (37/167 vs. 172/1086,P = 0.041). Multivariable logistic regression analysis revealed that decreased hemoglobin was associated with resistance to the initial treatment (odds ratio 1.53; 95% confidence interval 1.00-2.33;P = 0.048). Conclusions Decreased hemoglobin was significantly associated with resistance to initial treatment in patients with KD.