川崎病患儿血清脂联素水平的变化

目的 探讨川崎病(Kawasaki disease, KD)患儿血清脂联素的变化及意义.方法 选取KD 患儿45 例,其中冠状动脉损伤(CAL)患儿18 例,未合并CAL 患儿27 例;另选取健康儿童20 例作为对照组.采用ELISA 法检测血清脂联素水平,全自动生化测定仪检测血脂四项,包括甘油三酯(TG)、胆固醇(TC)、低密度脂蛋白(LDL-C)、高密度脂蛋白(HDL-C).结果 合并CAL 与未合并CAL 组急性期、亚急性期、恢复期血清脂联素水平均低于正常对照组(P<0.01);急性期与亚急性期其水平均低于恢复期(P<0.01).在急性期与恢复期,CAL 组血清脂联素水平显著高于未合并CAL 组(P<0.05).合并CAL 与未合并CAL 组血清TC、HDL、LDL 均较正常对照组降低(P<0.05).KD 患儿血清脂联素水平与TC、TG、CRP 水平及CAL 的发生呈明显正相关,r 分别为0.31、0.30、0.34、0.35,均P<0.05.结论 KD 患儿存在血脂紊乱及低脂联素水平;血清脂联素水平降低可能是全身炎症反应的结果;血清脂联素增加与CAL 的发生关系密切.     

川崎病患儿白细胞介素-15水平变化的临床意义

目的探讨白细胞介素-15（IL-15）在川崎病（KD）发病机制中的作用及其应用价值。方法选择2004年10月～2006年1月本院住院的30例KD患儿作为研究对象,采用酶联免疫吸附法（ELISA）检测KD患儿急性期和恢复期血清IL-15水平,同期检测30例下呼吸道感染发热期和20例正常健康儿童作为对照。结果急性期KD患儿血清IL-15水平明显高于健康对照组,二者比较有显著性差异（q=25.64P〈0.01）;恢复期KD患儿血清IL-15水平下降,但仍较健康对照组增高,二者比较有显著性差异（q=4.00P〈0.01）;KD患儿血清IL-15水平急性期与恢复期比较有显著性差异（t=14.87P〈0.01）。KD患儿急性期和恢复期血清IL-15水平均明显高于下呼吸道感染患儿急性期和恢复期,有显著性差异（急性期t=6.28P〈0.01;恢复期t=4.34P〈0.01）;急性期随KD患儿IL-15水平升高,ESR也相应升高,二者呈显著正相关（r=0.371P=0.044）,但与外周血WBC计数、CRP和血清清蛋白（ALB）变化无明显相关性;与IgG存在正相关性（r=0.372P=0.043）。结论IL-15参与KD的病理生理过程,IL-15可能促使免疫细胞大量激活,进而介导组织免疫病理损伤。IL-15水平变化反映KD的病情状况,可能为早期诊断提供一定线索。     

川崎病患儿血清抗内皮细胞抗体和抗中性粒细胞胞浆抗体检测的临床意义

目的 探讨抗内皮细胞抗体（AECA）和抗中性粒细胞胞浆抗体（ANCA）在川崎病（KD）及其冠状动脉损害（CAL）中的临床意义。方法 应用酶联免疫吸附试验定量检测42 例KD 患儿急性期、缓解期血清AECA 和ANCA 水平,并行心脏超声心动图了解CAL 发生情况。随机选取20 例因呼吸道感染发热患儿和15 例外科择期手术患儿分别作为发热对照组和普通对照组。结果 急性期KD 组AECA、ANCA 水平均显著高于两对照组（PPPPr=0.88,P结论 AECA、ANCA 可能参与了KD 血管炎及其CAL 的发生。急性期血清AECA、ANCA 对早期难以确诊的KD 有参考价值,ANCA 水平异常增高对CAL 有一定的预警价值。     

川崎病患儿血清白介素-17的变化

目的探讨川崎病(KD)患儿白介素–17(IL-17)水平变化的临床意义。方法收集KD患儿40例,其中12例急性期有超声心动图异常;另选年龄匹配的非KD患儿25例。采用双抗体夹心酶联免疫吸附法检测KD患儿急性期、恢复期及非KD患儿的血清IL-17水平,同时检测C反应蛋白(CRP)、球蛋白、白蛋白。结果 KD患儿急性期血清IL-17水平明显高于恢复期及非KD患儿,差异有统计学意义(P<0.05);KD患儿恢复期血清IL-17水平与非KD患儿差异无统计学意义(P>0.05);急性期超声心动图异常KD患儿的血清IL-17水平高于超声心动图正常的患儿,差异有统计学意义(P<0.05)。KD患儿急性期血清IL-17与CRP、球蛋白水平呈正相关(r=0.750、0.750,P均<0.05),而与白蛋白水平呈负相关(r=-0.779,P<0.05)。结论 IL-17参与KD的免疫损伤过程,血清IL-17水平是KD活动的指标之一,IL-17水平与心血管损害相关。     

基质金属蛋白酶9及组织抑制物1对预测和早期诊断川崎病冠状动脉病变的意义

目的探讨川崎病（Kawasaki disease,KD）血清基质金属蛋白酶9（matrix metallopmteinase-9,MMP-9）及其特异性组织抑制物1（tissue inhibitor of metalloproteinase-1,TIMP-1）水平的动态变化在冠状动脉病变（coronary artery lesion,CAL）的预测和早期诊断中的临床价值。方法实验组KD合并CAL患儿15例,未合并CAL患儿44例,急性期静脉注射免疫球蛋白（intravenous immunoglobulin,IVIG）前后、亚急性期及恢复期各抽取1次外周静脉血,对照组为20例正常体检儿童。ELISA双抗体法测定血清MMP-9与TIMP-1含量。结果KD患儿急性期血清MMP-9含量、TIMP-1含量及MMP-9／TIMP-1均较正常对照组增高（P〈0、01）;IVIG干预后KD患儿血清MMP-9含量与MMP-9／TIMP-1比值降低（P〈0．01）;KD合并CAL患儿IVIG干预前血清MMP-9含量及血清MMP-9／TIMP-1比值高于无CAL患儿（P〈0．01）。结论川崎病冠状动脉病变患儿血清MMP-9含量与MMP-9／TIMP-1比值在急性期高于无冠状动脉病变患儿,提示MMP-9含量的急剧升高及与TIMP-1相互拮抗作用的失代偿可能是川崎病冠状动脉病变的高风险因素,动态监测血清MMP-9含量和（或）MMP-9／TIMP-1比值对预测和早期诊断川崎病合并冠脉病变具有重要的临床意义。     

经胸超声心动图和螺旋CT冠状动脉成像在川崎病冠状动脉病变随访中应用价值的比较

目的　比较经胸超声心动图（TTE）和螺旋CT冠状动脉成像（CTA）在川崎病（KD）患儿冠状动脉病变（CAL）随访中的价值。方法　回顾性分析青岛大学附属妇女儿童医院2017年6月至2020年1月收治的512例KD患儿的TTE和CTA资料。512例中29例于急性期TTE检查发现CAL而恢复期TTE显示冠状动脉正常,或急性期TTE检查冠状动脉正常但恢复期随访过程中TTE检查冠状动脉可疑异常,或多人次TTE检查冠状动脉测量结果不一致者,将其分为急性期合并CAL（急性期CAL）组以及急性期未合并CAL（急性期Non-CAL）组。所有患儿于恢复期行TTE和CTA检查,分析CAL好发部位、大小、数目和风险分级,比较TTE和CTA对KD患儿CAL的评估价值。结果　29例KD患儿恢复期TTE发现冠状动脉瘤/扩张数19支,CTA发现28支,其中急性期Non-CAL组TTE较CTA漏诊7支（P＜0.05）,分别为左冠状动脉主干（LMCA） 4支,冠状动脉左回旋支（LCX） 3支;两种检查方法对急性期CAL组CAL风险分级评估差异无统计学意义（P＞0.05）,但对急性期Non-CAL组CAL分级评估差异有统计学意义（P＜0.01）,其中TTE评估9例为CAL Ⅰ级,而CTA评估仅4例为Ⅰ级,6例为Ⅲa级,其中1例为TTE冠状动脉无异常。TTE测量的29例KD患儿的LMCA Z值较CTA小（P＜0.01）,而LAD Z值较CTA大（P＜0.05）;另外,急性期CAL组TTE显示分别有5例LMCA Z值和3例RCA Z值正常,但CTA均显示其Z值异常（P＜0.05）;急性期Non-CAL组TTE显示4例患儿LMCA Z值正常,而CTA显示其Z值异常（P＜0.05）。结论　对于急性期发生CAL但恢复期TTE检查正常或急性期未发现CAL而恢复期TTE疑似CAL者不宜单纯采用TTE评估CAL,而应给予CTA验证。     

川崎病患儿急性期IL-38和IL-1β水平及其临床意义

目的 通过检测川崎病（KD）患儿急性期血清细胞因子IL-38和IL-1β表达水平,分析IL-38和IL-1β与KD急性期炎症反应以及冠状动脉损伤的相关性,并进一步探讨其临床意义。方法 选取2015年7月至2016年6月住院的KD患儿40例为研究对象,其中冠状动脉损伤（CAL）组21例,非冠状动脉损伤（NCAL）组19例;另外选取性别、年龄相匹配的30例健康儿童和19例感染发热患儿作为健康对照组和发热对照组。采用酶联免疫吸附法（ELISA）检测40例川崎病（KD）患儿急性期血清细胞因子IL-38和IL-1β水平。采用Spearman秩相关分析IL-1β和IL-38分别与白细胞介素-6（IL-6）、C-反应蛋白（CRP）、血沉（ESR）、降钙素原（PCT）、氨基末端脑钠肽前体（NT-ProBNP）、甘油三酯（TG）和血总胆固醇（TC）的相关性。结果 KD患儿急性期血清IL-38水平明显低于健康对照组,但高于发热对照组（P < 0.05）;CAL组和NCAL组IL-38水平比较差异无统计学意义（P > 0.05）。KD患儿急性期IL-1β水平较健康对照组明显升高（P < 0.05）,但与发热照对组相比差异无统计学意义（P > 0.05）;CAL组和NCAL组IL-1β水平比较差异无统计学意义（P > 0.05）。未发现细胞因子IL-1β和IL-38与其他炎性指标（CRP、ESR、PCT、IL-6、NT-ProBNP）及血脂（TG、TC）之间存在相关性（P > 0.05）。结论 细胞因子IL-38参与KD急性期炎症反应且可能发挥与IL-1β促进炎症反应相反的抗炎作用,二者与KD伴冠状动脉损伤发生均无明显相关性。     

川崎病患儿急性期外周血单个核细胞NLRP3炎症小体的表达及其临床意义

目的 探讨Nod样受体蛋白3（NLRP3）炎症小体与川崎病（KD）患儿急性期炎症反应以及冠状动脉损伤的关系。方法 前瞻性纳入2017年1~10月住院的KD患儿42例为研究对象,其中伴冠状动脉损伤（CAL）9例,非冠状动脉损伤（NCAL）33例。另外选取性别、年龄相匹配的15例肺炎发热患儿作为发热对照组,15例健康儿童作为健康对照组。采用实时荧光定量PCR检测外周血单个核细胞NLPR3炎症小体（NLRP3、ASC和caspase-1） mRNA的表达。采用Spearman秩相关分析法评估NLRP3 mRNA表达与血清C反应蛋白（CRP）、红细胞沉降率（ESR）、白细胞介素-6（IL-6）、白细胞介素-1β（IL-1β）、降钙素原、白蛋白及前白蛋白水平的相关性。结果 KD组急性期外周血NLRP3、ASC和caspase-1 mRNA表达明显高于发热对照组及健康对照组（P < 0.05）;CAL组患儿NLRP3 mRNA表达明显高于NCAL组（P < 0.05）。KD患儿急性期NLRP3 mRNA表达与CRP、IL-6、IL-1β、前白蛋白水平存在相关性（r_s分别为0.449、0.376、0.427、-0.416,均P < 0.05）。结论 NLRP3炎症小体可能参与了KD急性期炎症反应及CAL的发生。     

川崎病患儿血清可溶性血管细胞黏附分子-1、肿瘤坏死因子-α水平变化的意义

目的探讨可溶性血管细胞黏附分子-1（sVCAM-1）与肿瘤坏死因子-α（TNF-α）在川崎病（KD）发病中的意义。方法采用双抗体夹心酶联免疫法（ELISA）分别测定确诊为KD34例患儿急性期血清sVCAM-1、TNF-α水平,测定其中32例恢复期患儿血清sVCAM-1、TNF-α水平,26例健康儿童为健康对照组。结果KD组血清急性期sVCAM-1、TNF-α[（97.8±35.6）、（73.9±21.7）μg/L]均高于健康对照组[（41.2±8.9）、（2.7±1.8）μg/L],差异有显著性（Pa〈0.01）;KD患儿恢复期血清sVCAM-1、TNF-α水平[（46.9±16.8）、（4.3±2.9）μg/L]下降显著与急性期比较差异有显著性（Pa〈0.01）;而KD恢复期患儿与健康对照组无显著差异（P〉0.05）,且sVCAM-1与TNF-α呈正相关（r=0.798P〈0.001）。结论sVCAM-1、TNF-α可能参与KD发病的病理过程,血清sVCAM-1、TNF-α检测有助于对KD病情发展作出判断。     

川崎病患儿急性期外周血Th9细胞与细胞因子IL-9的变化及临床意义

目的探讨辅助性T细胞9(Th9)及其细胞因子白细胞介素-9(IL-9)在川崎病(KD)患儿急性期外周血的表达及临床意义。方法选取2014年4月至2015年7月45例急性期川崎病患儿进行研究,并且对其进行恢复期随访;另取健康体检儿童45例作为对照组。采用流式细胞术检测外周血Th9水平及酶联免疫吸附试验(ELISA)检测血清IL-9水平。结果 KD患儿急性期Th9及IL-9水平明显高于恢复期和对照组(P0.05);而恢复期患儿与对照组的Th9、IL-9水平差异均无统计学意义(P0.05)。急性期的Th9与CRP、PCT、ESR、PLT及球蛋白水平呈正相关(r=0.324、0.402、0.382、0.467、0.386,均P0.05),与血清白蛋白呈负相关(r=-0.306;P0.05);IL-9水平与CRP、PCT、ESR、PLT、球蛋白水平呈正相关(r=0.365、0.456、0.403、0.423、0.453,均P0.05),与血清白蛋白呈负相关(r=-0.343;P0.05)。结论 KD患儿急性期外周血Th9细胞及其细胞因子IL-9水平明显升高,恢复期降至正常;且Th9表达及IL-9水平与急性期指标密切相关。推测Th9细胞与IL-9在KD的发病及转归过程起重要作用。     

Serum hepatocyte growth factor combined with vascular endothelial growth factor as a predictive indicator for the occurrence of coronary artery lesions in Kawasaki disease

We investigated the possible use of serum hepatocyte growth factor (HGF) and vascular endothelial growth factor (VEGF) levels as a predictive indicator for the occurrence of coronary artery lesions (CAL) in Kawasaki disease (KD). Serum HGF and VEGF levels were measured by enzyme-linked immunosorbent assay in 41 patients with KD and 25 afebrile controls. Serum HGF levels of patients in the acute phase of KD were significantly higher than those of afebrile controls (Pc < 0.05) and decreased to lower levels during recovery (P < 0.0001). Univariate analysis showed significant correlations between occurrence of CAL and five variables: duration of fever (P=0.018), serum C-reactive protein concentration (P = 0.024), albumin concentration (P=0.009). serum VEGF level (P=0.009) and serum HGF level (P=0.035). Furthermore, multivariate analysis revealed that serum HGF and VEGF levels and presence of oedema were major risk factors for the occurrence of CAL. For prediction of the development of CAL, we established a new risk classification system with these three variables, which showed a sensitivity of 100% and a specificity of 94.4%. CONCLUSION: these data show that hepatocyte growth factor, together with vascular endothelial growth factor, might play an important role in the pathophysiology of Kawasaki disease and their serum levels could be a powerful predictor for the development of coronary artery lesions.     

P选择素及E选择素在小儿川崎病血管损伤中的作用机制及其意义

目的探讨P选择素(P-selectin, PS)、E选择素(E-selectin, ES)在小儿川崎病血管损伤中的作用机制,寻找其与冠状动脉(简称冠脉)损伤之间直接关系的依据.方法应用酶联免疫吸附实验(ELISA)双抗体夹心法、放免法检测36例川崎病(KD)患儿、20例发热疾病患儿、30例健康对照组儿童的PS、ES、血栓素(TXB2)、6酮前列腺素F1α(6-KPGF1α),并将KD患儿分为急性期、亚急性期、恢复期;有冠脉损伤(CAL)组与无冠脉损伤(NCAL)组,根据初始应用静脉丙种球蛋白(IVIG)48小时是否热退分为IVIG有效组与IVIG无效组.结果 KD患儿组的PS、ES急性期[ (211±28、186±14)ng/ml ]、亚急性期[(238±27、151±13)ng/ml]和恢复期[(198±21、100±9) ng/ml]均高于健康对照组 [(102±36、72±10)ng/ml],差异有显著性(P<0.01);治疗后PS仍维持较高水平,但IVIG有效组PS、ES下降与急性期相比差异有显著性(P<0.01);CAL组PS、ES[(281±78、210±52)ng/ml]水平明显高于NCAL组[(217±15、108±10)ng/ml,P<0.01 ],IVIG有效组PS、ES水平治疗后2周比治疗后1周降低,差异有显著性(P<0.01),IVIG无效组PS水平治疗后2周仍高于治疗后 1周,但差异无显著性(P>0.05);治疗后1周IVIG无效组与IVIG有效组PS水平未降低,差异无显著性(P>0.05);治疗后2周IVIG无效组PS、ES水平仍显著高于IVIG有效组(P<0.01),差异有显著性,PS的高峰期在亚急性期.KD患儿急性期TXB2水平显著升高,与健康对照组相比差异有显著性(P<0.01),亚急性期与正常组、CAL与NCAL组间差异无显著性(P>0.05),治疗后TXB2水平迅速降低;6-KPGF1α急性期、亚急性期、恢复期水平显著低于健康对照组(P<0.01);治疗后2周仍未达正常水平,CAL与NCAL组间差异无显著性(P>0.05);发热疾病组急性期PS、ES水平与健康对照组相比差异无显著性(P>0.05);KD组患儿ES与CRP水平差异有极显著性(r＝0.79 ,P<0.01),发热疾病组ES与CRP水平差异无显著性,KD组患儿PS与血小板计数(PLT)水平差异有极显著性(r＝0.75 ,P<0.01),发热疾病组PS与PTL差异无显著性.结论 PS、ES水平在KD患儿组急性期和亚急性期升高可能在川崎病患儿血管损伤的病理生理发生机制中起重要作用,PS、ES具有预示KD患儿CAL潜在的可能性.     

Serum levels of neutrophil activation cytokines in Kawasaki disease

BACKGROUND: The aim of the present study was to investigate whether neutrophils are early effector cells for vascular endothelial damage in the acute phase of Kawasaki disease (KD) by examining serial changes in neutrophil counts and serum levels of neutrophil activation cytokines, such as granulocyte colony stimulating factor (G-CSF) and interleukin (IL)-8. METHODS: From October 1994 to June 1998, a total of 52 patients with KD were included in the study. Thirty-three patients had some infectious diseases, while 20 healthy children served as control subjects. Serial changes in neutrophils were counted by the optimal Wright-Giemsa staining method and serum levels of IL-8 and G-CSF in patients with KD were measured by an enzyme-linked immunosorbent assay system. RESULTS: Serum G-CSF levels both before and after intravenous immunoglobulin therapy (IVIG; P<0.05) and neutrophil counts after IVIG (P<0.005) were higher in KD patients with coronary arterial lesions (CAL) than those without CAL. However, serum IL-8 levels before and after IVIG showed no significant differences in these two groups. CONCLUSIONS: These data suggest that neutrophils may be important as early effector cells for vascular endothelial damage and that G-CSF may play a more important role than IL-8 in KD.     

川崎病患儿血清中基质金属蛋白酶-9及其组织抑制物-1的变化

目的评价基质金属蛋白酶-9(MMP-9)及其组织抑制物-1(TIMP-1)在川崎病(KD)发病机制中的作用。方法采用酶联免疫吸附法(ELISA)检测33例KD患儿治疗前后血清MMP-9及TIMP-1的含量,并设置无热、发热对照组;同时检测KD患儿外周血中性粒细胞计数、C反应蛋白(CRP)等指标。结果KD组患儿急性期MMP-9血清水平较对照组升高,合并冠脉损害(CAL)者尤甚,治疗后降至正常;MMP-9的升高与外周血中性粒细胞计数、CRP呈正相关;KD患儿无论是否合并CAL,其急性期TIMP-1血清水平均高于对照组,治疗后虽有所下降,仍较对照组高;MMP-9/TIMP-1比值在KD组急性期与对照组差异无统计学意义,治疗后较无热对照组降低,与发热对照组差异无统计学意义。结论MMP-9作为一种损害因素参与了川崎病的病理生理过程,而TIMP-1可抑制其作用;MMP-9的水平可反映KD的严重程度。     

Water retention in the acute phase of Kawasaki disease: relationship between oedema and the development of coronary arterial lesions

Despite intravenous immunoglobulin therapy, a certain percentage of patients with Kawasaki disease (KD) still develop coronary arterial lesions (CAL). In an effort to find new combined therapies to reduce the incidence of CAL, we focused on the oedema which can be an important sign of the increased vascular permeability in KD. A total of 127 patients with KD were included in the retrospective study. Serial weekly changes in serum sodium and albumin levels from the 1st to the 4th week of illness were examined. In addition, the maximum rate of increase in body weight from admission to the 14th day of illness was evaluated. Serum sodium levels (mEq/l) in only the 2nd week of illness were significantly lower in patients with CAL than in those without CAL (mean ± SD, 135.5±4.5 versus 138.0±2.4, P <0.05). Serum albumin levels in all 4 weeks were significantly lower in patients with CAL than in those without CAL ( P <0.001). The maximum rate (%) of increase in body weight from admission to the 14th day of illness was significantly higher in patients with CAL than in those without CAL (ranges and median values, 0–12.3 (7.0) versus 0–10.3 (3.2), P <0.001). Conclusion:these results suggest that water retention in the acute phase of Kawasaki disease may be a risk factor for CAL, and water intake of both infusion and oral intake should be kept to a minimum in order to avoid progressive oedema.Abbreviations ASA acetylsalicylic acid - CAL coronary arterial lesions - HGF hepatocyte growth factor - IVIG intravenous immunoglobulin - KD Kawasaki disease - MBW maximum rate of increase in body weight - VEGF vascular endothelial growth factor     

Neutrophils and mononuclear cells express vascular endothelial growth factor in acute Kawasaki disease: its possible role in progression of coronary artery lesions

Kawasaki disease (KD) is a syndrome of systemic vasculitis of unknown etiology that is complicated by coronary artery lesions (CAL), leading occasionally to cardiac ischemic sequelae. To examine whether vascular endothelial growth factor (VEGF) is responsible for CAL in KD, we determined serum VEGF levels by ELISA and peripheral blood mononuclear cell (PBMC) and neutrophil VEGF expression by immunoblot analysis. Significantly increased levels of VEGF were demonstrated in acute KD as well as in other vasculitis syndromes (p < 0.0001). In the 10 KD patients with CAL, serum VEGF levels were maximal approximately 2 wk post-onset when CAL generally develops and were significantly higher than in 20 patients without CAL (mean, 474 and 241 pg/mL, respectively; p = 0.00015). During the same period, immunoblot analysis revealed maximal VEGF expression in PBMC, corresponding to serum VEGF levels in most patients and being particularly marked in patients with CAL (p < 0.01). Neutrophils expressed VEGF only in the early stage of acute KD and declined rapidly in the majority of KD patients regardless of the presence of CAL, showing a strikingly different expression pattern than that for PBMC. Predominant VEGF expression by PBMC was also demonstrated in patients with other vasculitis syndromes and only faintly in normal controls. The results suggest that VEGF is generated dynamically in KD, presumably reflecting its disease activity. Neutrophil-derived VEGF may play a role in regulating early vascular responses, whereas PBMC-derived VEGF may contribute to later vascular injury and remodeling.     

Enhanced iNOS expression in leukocytes and circulating endothelial cells is associated with the progression of coronary artery lesions in acute Kawasaki disease

Nitric oxide (NO) serves many vasoprotective roles, but the massive release of NO causes arterial wall degeneration. We investigated whether enhanced nitric oxide synthase (iNOS) expression in peripheral blood leukocytes and circulating endothelial cells mirrors the progression of coronary arterial lesions in 55 children with acute Kawasaki disease (KD), including 24 with and 31 without coronary artery lesions (CAL). Patients were treated with i.v. gamma-globulin at the time of diagnosis and blood samples were collected before and after treatment. The cellular origin of NO synthesis was determined by flow cytometric analysis of iNOS expression in peripheral blood, and by immunohistochemical analysis of circulating endothelial cells and coronary arteries. iNOS expression in neutrophils peaked at the time of diagnosis, but did not peak in monocytes until 2 wk post onset of disease. Levels were significantly higher in both cell types in patients with CAL (p = 0.001 and p = 0.035, respectively). In addition, the number of circulating endothelial cells and levels of iNOS expression were higher in patients with CAL (p = 0.011 and p = 0.012, respectively). Immunohistochemical analysis of the coronary arteries from three patients with acute KD revealed iNOS immunoreactivity in endothelial cells, as well as infiltrating monocytes/macrophages in the aneurysms. We conclude that the expression of iNOS in peripheral blood leukocytes, as well as circulating endothelial cells, correlates with the severity of coronary arterial wall injury and the progression of CAL in patients with acute KD.