Delta-neutrophil index: a potential predictor of coronary artery involvement in Kawasaki disease by retrospective analysis

DNI is the immature granulocyte fraction provided by a blood cell analyzer, which is determined by subtracting the fraction of mature polymorphonuclear leukocytes from the sum of myeloperoxidase-reactive cells. We aimed to evaluate the role of Delta-neutrophil index (DNI) in cardiac prognosis prediction in children with Kawasaki disease (KD). Medical records of 193 patients were retrospectively reviewed. The values of DNI, white blood cells, erythrocyte sedimentation rate, the percent of polymorphonuclear leucocytes, C-reactive protein, aspartate transaminase, alanine aminotransferase, total bilirubin data of children with KD were analyzed. Also, sex and age of children were compared. The value of DNI was higher in children with cardiac complications [median 0.8 (0–0.26) vs 5.3 (3.55–8.95); P < 0.001]. The ROC curves showed that DNI was a better predictor of cardiac complications than other parameters. The best cutoff value for DNI to predict cardiac complications was 5.55% with sensitivity of 80% and specificity of 82% (AUC 0.883, 95% confidence interval [CI] 0.807–0.959, P < 0.05). DNI could serve as a facile and useful marker to predict cardiac complications in children with KD, as it is included in a routine complete blood count.