Objective: To evaluate the predictive value of serum ferritin (SF) and construct a novel predictive model for intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD) (IVIGRKD). Methods: The clinical data of 422 children with KD from January 2017 to December 2019 in Quanzhou Women's and Children's Hospital were retrospectively analyzed. According to the response to IVIG, they were divided into IVIG-resistant group and IVIG-sensitive group. Forty-one clinical indicators including general characteristics and laboratory results were compared between the two groups. Comparisons between groups were performed with unpaired Student t test or Mann-Whitney U test or chi-square test. Receiver operating characteristic (ROC) curve was applied to evaluate the predictive value of SF for IVIGRKD. Binary Logistic regression analysis was used to test whether SF was an independent risk factor for IVIGRKD. Meanwhile, a novel predictive scoring system was established. The comparisons between the new predictive scoring system with four commonly used prediction scoring systems were conducted. Results: A total of 422 KD cases (285 males and 137 females, 17.0 (9.0,29.0) years of age) were enrolled and divided into IVIG-resistant group (n=57) and IVIG-sensitive group (n=365). Seventeen clinical indicators differed significantly between the two groups. SF level of the IVIG-resistant group was significantly higher than that of the sensitive group (245.0 (131.0, 519.0) vs. 145.0 (92.5, 232.5) μg/L, Z=-5.109, P<0.05). ROC curve showed that the Youden index of SF for predicting IVIGRKD was 0.326 (cutoff value 403.5 μg/L). Binary logistic regression analysis showed that SF, days of illness at initial IVIG treatment, cervical lymphadenopathy, pleomorphic rash, white blood cell, C-reactive protein (CRP), activated partial thromboplastin time (APTT), alanine transaminase (ALT) and creatinine were independent risk factors for IVIGRKD. A novel prediction model was constructed, and the cutoff points and score points were as follows: pleomorphic rash, 2 points; cervical lymphadenopathy, 1 point; SF≥ 403.5 μg/L, 1 point; white blood cell ≥ 18.3×109/L, 1 point; CRP≥83.1 mg/L, 1 point; APTT≥25.3 s, 1 point; ALT≥37.5 U/L, 1 point. And patients with scores of 4 or more were at high-risk for IVIGRKD. The Youden index of the four commonly used scoring systems ranged from 0.315 to 0.512. However, the Youden index of the new scoring system was 0.695 (sensitivity 0.772, specificity 0.923) and was the highest among the five scoring systems. Conclusions: SF shows well predictive efficiency for IVIGRKD and is an independent risk factor for IVIGRKD. SF can be used as a new predictor of IVIGRKD.
目的： 分析血清铁蛋白（SF）对丙种球蛋白无反应型川崎病（IVIGRKD）的预测价值并建立新的预测模型。 方法： 回顾性收集泉州市妇幼保健院2017年1月至2019年12月收治的422例川崎病患儿的病例资料，根据是否对静脉用丙种球蛋白（IVIG）治疗敏感分为IVIG耐药组和IVIG敏感组。对比分析两组患儿的一般临床特征、实验室检测结果等41项临床指标，组间比较采用t检验、Mann-WhitneyU检验或χ²检验。运用受试者工作特征（ROC）曲线分析SF对IVIGRKD的预测效能，运用二元Logistic回归分析研究SF是否为IVIGRKD的独立危险因素，并建立新的预测评分系统，检测新评分法和4个常用预测评分系统的预测效能并进行比较。 结果： 422例川崎病患儿中男285例、女137例，年龄17.0（9.0，29.0）月龄，其中IVIG耐药组57例、IVIG敏感组365例。耐药组SF水平明显高于敏感组［245.0（131.0，519.0）比 145.0（92.5，232.5）μg/L，Z=-5.109，P<0.05］，ROC曲线分析SF取截断值403.5 μg/L时，SF预测IVIGRKD 的Youden指数为0.326，预测效能良好。二元Logistic回归分析结果显示SF、初次IVIG 治疗时病程、颈淋巴结肿大、多形性皮疹、白细胞计数、C反应蛋白（CRP）、活化部分凝血活酶时间（APTT）、丙氨酸转氨酶（ALT）、肌酐这9项指标是IVIGRKD的独立危险因素，最终建立新预测模型：多形性皮疹（2分），颈淋巴结肿大（1分），SF≥403.5 μg/L（1分），白细胞计数≥18.3×109/L（1分），CRP≥83.1 mg/L（1分），APTT≥25.3 s（1分），ALT≥37.5 U/L（1分）；≥4分为高危。4个常用评分系统的Youden指数为0.315~0.512，预测效能均尚可，新评分法灵敏度0.772，特异度0.923，Youden指数0.695。 结论： SF对IVIGRKD的预测效能良好，且是独立危险因素之一，SF可作为一项新的IVIGRKD预测指标。.