The Validity of a Scoring System in Predicting Intravenous Immunoglobulin Treatment Failure in Children With Kawasaki Disease

Abstract

Background: Between 10 and 20% of children with Kawasaki disease (KD) will not respond to intravenous immunoglobulin (IVIG) treatment, and are prone to coronary abnormalities. A variety of predicting scoring systems, including the Kobayashi system, have been proposed, but have not yet been evaluated using Iranian patients. Objectives: To evaluate the Kobayashi scoring system with regard to predicting response to IVIG treatment in Iranian children. Patients and Methods: All patients who received a final diagnosis of KD at Aliasghar children’s hospital between 1982 and 2013, and who met the inclusion criteria, were enrolled in this retrospective cohort study. We excluded patients with missing data, abnormal echocardiographic finding on admission, late admission, atypical or afebrile cases, and those who had received an insufficient amount of IVIG. We compared demographic and echocardiographic data before IVIG, and within 7 days of treatment, as well as C reactive protein (CRP), sodium, aspartate aminotransferase, platelet levels, neutrophil percentage, age of patients, and duration of fever before IVIG administration, in treatment responders and non-responders. Results: Of the 141 cases, 97 patients met the criteria and were enrolled. Of these, 19 (19.6%) did not respond to IVIG. A total of 61.8% of patients were male, and the mean patient age was 36.9 months (SD = 32.1 months). Echocardiographic evaluation revealed early coronary involvement in 15.3% of patients, and coronary abnormalities were diagnosed in 10% of patients within the first 10 days of presentation and concurrent with their IVIG treatment. A between-groups comparison of quantitative CRP, absolute neutrophil count, and platelet count showed that platelet count alone was significantly higher in nonresponders (P = 0.04). With regard to items of Kobayashi scoring system, data were present for just 41 cases, but a significant difference between the two groups was shown, with the treatment-refractory group having a significantly higher score (P = 0.002). Receiver-operating characteristic curve analysis revealed that the optimum cut-off point for our population would be 2, which makes the sensitivity of the test equal to 75%, with a specificity of 60%. Conclusions: This preliminary study showed that patients with KD and a high Kobayashi score are at greater risk of being unresponsive to IVIG treatment. Further studies, preferably multicenter evaluations, are required in order to understand the exact application of various scoring systems in the management of people with KD in Iran.