Kawasaki disease: infection, immunity and genetics

Correlation of HAMP gene polymorphisms and expression with the susceptibility and length of hospital stays in Taiwanese children with Kawasaki disease

Kawasaki disease (KD) is a form of systemic vasculitis. Regarding its pathogenesis, HAMP gene encoding hepcidin, which is significant for iron metabolism, has a vital function. In this study, we recruited a total of 381 KD patients for genotyping. Data from 997 subjects (500 subjects from cohort 1; 497 subjects from cohort 2) were used for analysis. Using TaqMan allelic discrimination, we determined five tag SNPs (rs916145, rs10421768, rs3817623, rs7251432, and rs2293689). Treatment outcome data related to such clinical phenotypes as coronary artery lesions (CAL), coronary artery aneurysms (CAA), and intravenous immunoglobulin (IVIG) effects were also collected. Furthermore, we measured plasma hepcidin levels with an enzyme-linked immunosorbent assay. We found that HAMP gene polymorphism (rs7251432, and rs2293689) was significantly correlated with KD risk and that plasma hepcidin levels both before and after IVIG treatment had a significantly positive correlation with length of hospital stays (R = 0.217, p = 0.046 and R = 0.381, p < 0.0001, respectively). In contrast, plasma hepcidin levels has a negative correlation with KD patients' albumin levels (R = -0.27, p < 0.001) prior to IVIG treatment. This study's findings indicate that HAMP might have a role in the disease susceptibility, as well as its expressions correlated length of hospital stays, and albumin levels in Taiwanese children with KD.

Identifying genetic hypomethylation and upregulation of Toll-like receptors in Kawasaki disease

Kawasaki disease (KD) is an acute febrile systemic vasculitis that occurs in children and is characterized by elevated levels of proinflammatory cytokines. Toll-like receptors (TLRs) serve as the sensor arm of the innate immune system and induce proinflammatory cytokine expressions.

We recruited a total of 18 paired KD patients, before intravenous immunoglobulin (IVIG) and at least 3 weeks after IVIG treatment, 18 healthy controls, and 18 febrile controls. For TLR genes and their cytosine-phosphate-guanine (CpG) markers, we used Affymetrix GeneChip^® Human Transcriptome Array 2.0 and Illumina HumanMethylation450 BeadChip to evaluate gene expression levels and methylation patterns, respectively.

KD patients demonstrated a significantly differential expression of TLR mRNA levels compared to both the healthy and febrile controls, with only TLR 3 and 7 not differing between the KD patients and the controls. After patients underwent IVIG treatment, the TLR mRNA levels, except for TLR3, decreased significantly in KD patients. In contrast, the methylation status of the CpG sites of TLR1, 2, 4, 6, 8, and 9 demonstrated an opposite tendency between the two stages of both the KD samples and the controls.

TLRs, particularly TLR1, 2, 4, 6, 8, and 9, may stimulate the immunopathogenesis of KD. These results are among the first to use TLRs to prove that a bacterial inflammatory response may trigger KD.

Preventing coronary artery lesions in Kawasaki disease

A form of systemic vasculitis that affects mostly small and medium-sized vessels, Kawasaki disease (KD) is most commonly found in children under the age of 5 years old. Though its etiology is unknown, KD has been the most frequent acquired heart disease in developing countries. Its incidence has increased over recent decades in many centuries, including Japan, Korea, and China. The most severe complications of KD are coronary artery lesions (CAL), including dilation, fistula, aneurysm, arterial remodeling, stenosis, and occlusion. Aneurysm formation has been observed in 20–25% of KD patients that do not receive intravenous immunoglobulin (IVIG) treatment, and in 3–5% that do receive it. Coronary artery dilation has been found in about 30% of KD patients in the acute stage, although mostly in the transient form. Diminishing the occurrence and regression of CAL is a vital part of treating KD. In this review article, I demonstrate the clinical method to prevent CAL formation used at the Kawasaki Disease Center in Taiwan.

Anemia in Kawasaki Disease: Hepcidin as a Potential Biomarker

Kawasaki disease (KD) is an autoimmune-like disease and acute childhood vasculitis syndrome that affects various systems but has unknown etiology. In addition to the standard diagnostic criteria, anemia is among the most common clinical features of KD patients and is thought to have a more prolonged duration of active inflammation. In 2001, the discovery of a liver-derived peptide hormone known as hepcidin began revolutionizing our understanding of anemia’s relation to a number of inflammatory diseases, including KD. This review focuses on hepcidin-induced iron deficiency’s relation to transient hyposideremia, anemia, and disease outcomes in KD patients, and goes on to suggest possible routes of further study.

Vascular function long term after Kawasaki disease: another piece of the puzzle?

BACKGROUND

Kawasaki disease is an acute systemic vasculitis. Cardiac complications are frequent and include endothelial dysfunction in patients with coronary anomalies. Thus far, endothelial dysfunction in patients with no coronary lesions is poorly understood. Our aim was to access the vascular function in adolescents and young adults long term after Kawasaki disease, but without coronary aneurysms or any other cardiac risk factors.

METHODS

We carried out a single-centre prospective study in a Portuguese population. We evaluated two groups of subjects: (1) Kawasaki disease patients over 11 years of age, diagnosed >5 years ago, with no coronary lesions or any other risk factors for cardiovascular disease; (2) control group of individuals without cardiovascular risk factors. Patients and controls were clinically assessed. Endo-PAT and carotid intima-media thickness assessment were performed to determine vascular function.

RESULTS

In total, 43 Kawasaki disease patients were assessed and compared with 43 controls. Kawasaki disease patients presented a decreased reactive hyperaemia index compared with controls (1.59±0.45 versus 1.98±0.41; p<0.001). Augmentation index was similar in both groups (-4.5±7 versus -5±9%; p 0.6). The mean carotid intima-media thickness was not significantly increased in the Kawasaki disease group. There were no statistically significant changes with regard to laboratory data.

CONCLUSIONS

Children with Kawasaki disease may have long-term sequelae, even when there is no discernible coronary artery involvement in the acute stage of the disease. Further research is needed to assess whether known strategies to improve endothelial function would bring potential benefits to Kawasaki disease patients.

Association of Attention deficit hyperactivity disorder and Kawasaki disease: a nationwide population-based cohort study

AIMS

The association between Kawasaki disease (KD) and Attention deficit hyperactivity disorder (ADHD) has rarely been studied. In this study, we investigated the hypothesis that KD may increase the risk of ADHD using a nationwide Taiwanese population-based claims database.

METHODS

Our study cohort consisted of patients who were diagnosed with KD between January 1997 and December 2005 (N = 651). For a comparison cohort, five age- and gender-matched control patients for every patient in the study cohort were selected using random sampling (N = 3255). The cumulative incidence of ADHD was 3.89/1000 (from 0.05 to 0.85) in this study. All subjects were tracked for 5 years from the date of cohort entry to identify whether or not they had developed ADHD. Cox proportional hazard regression analysis was performed to evaluate 5-year ADHD-free survival rates.

RESULTS

Of all patients, 83 (2.1%) developed ADHD during the 5-year follow-up period, of whom 21 (3.2%) had KD and 62 (1.9%) were in the comparison cohort. The patients with KD seemed to be at an increased risk of developing ADHD (crude hazard ratio (HR): 1.71; 95% confidence interval (CI) = 1.04-2.80; p < 0.05). However, after adjusting for gender, age, asthma, allergic rhinitis, atopic dermatitis and meningitis, the adjusted hazard ratios (AHR) of the ADHD in patients with KD showed no association with the controls (AHR: 1.59; 95% CI = 0.96-2.62; p = 0.07). We also investigated whether or not KD was a gender-dependent risk factor for ADHD, and found that male patients with KD did not have an increased risk of ADHD (AHR: 1.62; 95% CI = 0.96-2.74; p = 0.07) compared with the female patients.

CONCLUSIONS

The findings of this population-based study suggest that patients with KD may not have an increased risk of ADHD and whether or not there is an association between KD and ADHD remains uncertain.

Kawasaki disease: etiopathogenesis and novel treatment strategies

INTRODUCTION

Kawasaki disease is an acute febrile systemic vasculitis that predominantly occurs in children below five years of age. Its etiopathogenesis is still not clear, but it is thought to be a complex interplay of genetic factors, infections and immunity. Areas covered: This review article discusses in detail Kawasaki disease, with particular emphasis on the recent updates on its pathogenesis and upcoming alternate treatment options. Though self-limiting in many cases, it can lead to severe complications like coronary artery aneurysms and thrombo-embolic occlusions, and hence requires early diagnosis and urgent attention to avoid them. Intravenous immunoglobulin (IVIG) with or without aspirin has remained the sole treatment option for these cases, but 10-15% cases develop resistance to this treatment. Expert commentary: There is a need to develop additional treatment strategies for children with Kawasaki disease. Targeting different steps of pathogenesis could provide us with alternate therapeutic options.

Identification of Differentially Expressed Genes in Kawasaki Disease Patients as Potential Biomarkers for IVIG Sensitivity by Bioinformatics Analysis

Kawasaki disease (KD) is a leading cause of acquired heart disease predominantly affecting infants and young children. Intravenous immunoglobulin (IVIG) is applied as the most favorable treatment against KD, but IVIG resistant remains exist. Although several clinical scoring systems have been developed to identify children at highest risk of IVIG resistance, there is a need to identify sufficiently sensitive biomarkers for IVIG treatment. Some differentially expressed genes (DEGs) could be the promising potential biomarkers for IVIG-related sensitivity diagnosis. We employed a systematic and integrative bioinformatics framework to identify such kind of genes. The performance of the candidate genes was evaluated by hierarchical clustering, ROC analysis and literature mining. By analyzing three datasets of KD patients, 34 DEGs of the three groups have been found to be associated with IVIG-related sensitivity. A module of 12 genes could predict resistant group patients with high accuracy, and a module of ten genes could predict responsive group patients effectively with accuracy of 96 %. And three of them are most likely to serve as drug targets or diagnostic biomarkers in the future. Compared with unsupervised hierarchical clustering analysis, our modules could distinct IVIG-resistant patients efficiently. Two groups of DEGs could predict IVIG-related sensitivity with high accuracy, which are potential biomarkers for the clinical diagnosis and prediction of IVIG treatment response in KD patients, improving the prognosis of patients.

Hepcidin-Induced Iron Deficiency Is Related to Transient Anemia and Hypoferremia in Kawasaki Disease Patients

Kawasaki disease (KD) is a type of systemic vasculitis that primarily affects children under the age of five years old. For sufferers of KD, intravenous immunoglobulin (IVIG) has been found to successfully diminish the occurrence of coronary artery lesions. Anemia is commonly found in KD patients, and we have shown that in appropriately elevated hepcidin levels are related to decreased hemoglobin levels in these patients. In this study, we investigated the time period of anemia and iron metabolism during different stages of KD. A total of 100 patients with KD and 20 control subjects were enrolled in this study for red blood cell and hemoglobin analysis. Furthermore, plasma, urine hepcidin, and plasma IL-6 levels were evaluated using enzyme-linked immunosorbent assay in 20 KD patients and controls. Changes in hemoglobin, plasma iron levels, and total iron binding capacity (TIBC) were also measured in patients with KD. Hemoglobin, iron levels, and TIBC were lower (p < 0.001, p = 0.009, and p < 0.001, respectively) while plasma IL-6 and hepcidin levels (both p < 0.001) were higher in patients with KD than in the controls prior to IVIG administration. Moreover, plasma hepcidin levels were positively and significantly correlated with urine hepcidin levels (p < 0.001) prior to IVIG administration. After IVIG treatment, plasma hepcidin and hemoglobin levels significantly decreased (both p < 0.001). Of particular note was a subsequent gradual increase in hemoglobin levels during the three weeks after IVIG treatment; nevertheless, the hemoglobin levels stayed lower in KD patients than in the controls (p = 0.045). These findings provide a longitudinal study of hemoglobin changes and among the first evidence that hepcidin induces transient anemia and hypoferremia during KD's acute inflammatory phase.

[Coronary artery aneurysms probably due to Kawasaki's disease]

We report the case of a young adult admitted to the Abidjan Heart Institute for coronary angiography to explore unstable angina. Coronary angiography showed multiple aneurysms which suggested sequelae of misdiagnosed Kawasaki disease.

Interferon-gamma Genetic Polymorphism and Expression in Kawasaki Disease

Kawasaki disease (KD) is a systemic vasculitis of unknown etiology. IFNG gene encoding interferon (IFN)-γ, produced by natural killer cells and T cells, has been suggested to play an important role in the immunopathogenesis of Kawasaki disease. The aim of this study was to examin the correlation of gene polymorphisms of the IFNG gene and plasma levels of IFN-γ in KD patients and their outcomes.A total of 950 subjects (381 KD and 569 controls) were recruited. Three tagging single-nucleotide polymorphisms (rs2069718, rs1861493, rs2069705) were selected for TaqMan allelic discrimination assay. Clinical phenotypes, coronary artery lesions (CAL), coronary artery aneurysms (CAA) and intravenous immunoglobulin (IVIG) treatment outcomes were collected for analysis. Plasma IFN-γ levels were also measured with an enzyme-linked immunosorbent assay.Polymorphisms of the IFNG gene were significantly different between the normal controls and KD patients. The G allele of rs1861493 conferred a better response to IVIG treatment in KD patients. AA allele frequencies of rs1861493 were also associated with a significantly higher risk of CAA in KD patients. Furthermore, the plasma IFN-γ level was lower in the AA allele than in the GG allele of rs1861493 both before and after IVIG treatment in KD patients.This study provides the first evidence supporting an association between IFNG gene polymorphisms, susceptibility of KD, IVIG responsiveness, and plasma IFN-γ levels in KD patients.

Bull's eye dermatoscopy pattern at bacillus Calmette-Guérin inoculation site correlates with systemic involvements in patients with Kawasaki disease

For the past decades, although the rash at the bacillus Calmette-Guérin (BCG) inoculation site has been recognized as a diagnostic clue in Kawasaki disease, the present study is the first known one attempting to characterize BCG inoculation by dermatoscopy in Kawasaki disease and correlate the grade of BCG reaction with systemic involvement. Thirty-four patients diagnosed with Kawasaki disease by pediatric specialists were enrolled. We performed detailed history taking, laboratory examination, physical examination and dermatoscopy examinations. Based on the BCG reaction pattern by dermatoscopy, we were able to characterize three patterns: (A) Bull's eye pattern in 18 patients; (B) faint homogenous erythema in nine; and (C) central white patch in seven. Patients from group A exhibited the highest elevation of blood aspartate aminotransferase levels (P < 0.05). Notably, three patients from group A had a significantly dilated coronary artery despite i.v. immunoglobulin injection. We concluded that the bull's eye dermatoscopy sign is not only a useful diagnostic clue but also a severity biomarker in patients with Kawasaki disease.

Comparison between Kawasaki disease with lymph-node-first presentation and Kawasaki disease without cervical lymphadenopathy

Purpose

We evaluated the characteristics of patients with Kawasaki disease (KD) who presented with only fever and cervical lymphadenopathy on admission, and compared them with the characteristics of those who presented with typical features but no cervical lymphadenopathy.

Methods

We enrolled 98 patients diagnosed with KD. Thirteen patients had only fever and cervical lymphadenopathy on the day of admission (group 1), 31 had typical features with cervical lymphadenopathy (group 2), and 54 had typical features without cervical lymphadenopathy (group 3).

Results

The mean age (4.3±2.1 years) and duration of fever (7.5±3.6 days) before the first intravenous immunoglobulin (IVIG) administration were highest in group 1 (P=0.001). Moreover, this group showed higher white blood cell and neutrophil counts, and lower lymphocyte counts after the first IVIG administration as compared to the other groups (P=0.001, P=0.001, and P=0.003, respectively). Group 1 also had a longer duration of hospitalization and higher frequency of second-line treatment as compared to groups 2 and 3 (group 1 vs. group 2, P=0.000 and P=0.024; group 1 vs. group 3, P=0.000 and P=0.007). A coronary artery z score of >2.5 was frequently observed in group 1 than in group 3 (P=0.008).

Conclusion

KD should be suspected in children who are unresponsive to antibiotics and have prolonged fever and cervical lymphadenopathy, which indicates that KD is associated with the likelihood of requiring second-line treatment and risk of developing coronary artery dilatation.

Incidence Rate and Epidemiological and Clinical Aspects of Kawasaki Disease in Children of Maghrebi Origin in the Province of Quebec, Canada, Compared to the Country of Origin

The incidence of Kawasaki disease in Maghreb countries is apparently low, unlike those living in the province of Quebec, Canada. This retrospective study compared Maghrebi children living in Quebec to the countries of origin, Morocco, Algeria, and Tunisia. The annualized incidence rate in Quebec (18.49/year/100 000 children under 5 years of age) was 4 to 12 times higher than in Tunisia, Morocco, and Algeria (0.95, 4.52, and 3.15, respectively). The prevalence of incomplete diagnostic criteria was higher in Quebec at 39%, Morocco 43%, and Tunisia 39% compared to Algeria at 8%, with minimal delayed diagnosis (7%) only in Quebec compared to 30%, 35%, and 62%, respectively (P < .001). The rate of coronary aneurysms was comparable however (11% in Quebec vs 4%, 10%, and 25%, in Tunisia, Morocco, and Algeria, respectively; P = .31). The higher incidence of Kawasaki disease in the Maghreb community in Quebec versus the countries of origin seems due to underdiagnosis, which represents a public health concern in those countries.

High-Dose Aspirin is Associated with Anemia and Does Not Confer Benefit to Disease Outcomes in Kawasaki Disease

Background

Kawasaki disease (KD) is also known as multiple mucocutaneous lymph node syndrome of systemic vasculitis and is a leading cause of coronary artery lesions (CAL) in childhood. Intravenous immunoglobulin (IVIG) has been proven to effectively reduce the incidence of CAL, but the role and effect dose of aspirin in KD is still unclear. Moreover, overt bleeding and anemia are associated with the use of aspirin, and anemia is common in patients with KD. Thus, the aim of this study was conducted to compare the treatment efficacy, degree of anemia and inflammation, and changes in serum hepcidin in children who received a combination of high-dose aspirin and IVIG in the acute stage of KD, and those who received IVIG alone.

Materials and Methods

KD patients from two medical centers were retrospectively analyzed from 1999–2009. All patients were initially treated with a single dose of IVIG (2 g/kg) as the standard care of treatment. In group 1, high-dose aspirin was prescribed (> 30 mg/kg/day) until the fever subsided, and then low-dose aspirin (3–5 mg/kg/day) was prescribed until all the inflammation signs had resolved. In group 2, low-dose aspirin was prescribed without high-dose aspirin. Laboratory data were collected for analysis in both groups.

Results

A total of 851 KD patients (group 1, N = 305, group 2, N = 546) were enrolled in this study. There were no significant differences between group 1 and group 2 in terms of gender (p = 0.51), IVIG resistance rate (31/305 vs. 38/546, p = 0.07), CAL formation (52/305 vs. 84/546, p = 0.67), and duration of hospitalization (6.3 ± 0.2 vs. 6.7 ± 0.2 days, p = 0.13). There were also initially no significant differences in total white blood cell count, hemoglobin level, platelet count, and CRP before IVIG treatment between groups (all p>0.1). After IVIG treatment, group 1 had significantly lower levels of hemoglobin (p = 0.006) and higher CRP (p<0.001) as well as a smaller decrease in CRP level (p = 0.012). Furthermore, there was also a higher serum level of hepcidin and a delayed decrease in hepcidin level after receiving IVIG in group 1 (p = 0.04 and 0.02, respectively).

Conclusions

These results provide evidence demonstrating that high-dose aspirin in the acute phase of KD does not confer any benefit with regards to inflammation and it does not appear to improve treatment outcomes. Therefore, high-dose aspirin is unnecessary in acute phase KD.

Gene-Gene Associations with the Susceptibility of Kawasaki Disease and Coronary Artery Lesions

Kawasaki disease (KD) is a systemic vasculitis primarily affecting children < 5 years old. Genes significantly associated with KD mostly involve cardiovascular, immune, and inflammatory responses. Recent studies have observed stronger associations for KD risk with multiple genes compared to individual genes. Therefore, we investigated whether gene combinations influenced KD susceptibility or coronary artery lesion (CAL) formation. We examined 384 single-nucleotide polymorphisms (SNPs) for 159 immune-related candidate genes in DNA samples from KD patients with CAL (n = 73), KD patients without CAL (n = 153), and cohort controls (n = 575). Individual SNPs were first assessed by univariate analysis (UVA) and multivariate analysis (MVA). We used multifactor dimensionality reduction (MDR) to examine individual SNPs in one-, two-, and three-locus best fit models. UVA identified 53 individual SNPs that were significantly associated with KD risk or CAL formation (p < 0.10), while 35 individual SNPs were significantly associated using MVA (p ≤ 0.05). Significant associations in MDR analysis were only observed for the two-locus models after permutation testing (p ≤ 0.05). In logistic regression, combined possession of PDE2A (rs341058) and CYFIP2 (rs767007) significantly increased KD susceptibility (OR = 3.54; p = 4.14 x 10⁻⁷), while combinations of LOC100133214 (rs2517892) and IL2RA (rs3118470) significantly increased the risk of CAL in KD patients (OR = 5.35; p = 7.46 x 10⁻⁵). Our results suggest varying gene-gene associations respectively predispose individuals to KD risk or its complications of CAL.

Characterization of the gut microbiota of Kawasaki disease patients by metagenomic analysis

Kawasaki disease (KD) is an acute febrile illness of early childhood. Previous reports have suggested that genetic disease susceptibility factors, together with a triggering infectious agent, could be involved in KD pathogenesis; however, the precise etiology of this disease remains unknown. Additionally, previous culture-based studies have suggested a possible role of intestinal microbiota in KD pathogenesis. In this study, we performed metagenomic analysis to comprehensively assess the longitudinal variation in the intestinal microbiota of 28 KD patients. Several notable bacterial genera were commonly extracted during the acute phase, whereas a relative increase in the number of Ruminococcus bacteria was observed during the non-acute phase of KD. The metagenomic analysis results based on bacterial species classification suggested that the number of sequencing reads with similarity to five Streptococcus spp. (S. pneumonia, pseudopneumoniae, oralis, gordonii, and sanguinis), in addition to patient-derived Streptococcus isolates, markedly increased during the acute phase in most patients. Streptococci include a variety of pathogenic bacteria and probiotic bacteria that promote human health; therefore, this further species discrimination could comprehensively illuminate the KD-associated microbiota. The findings of this study suggest that KD-related Streptococci might be involved in the pathogenesis of this disease.

Assessment of coronary ischaemia by myocardial perfusion dipyridamole stress technetium-99 m tetrofosmin, single-photon emission computed tomography, and coronary angiography in children with Kawasaki disease: pre- and post-coronary bypass grafting

BACKGROUND

Coronary artery lesions in Kawasaki disease invasively assessed by coronary angiography. Evaluation of myocardial perfusion by single-photon emission computed tomography may identify the haemodynamic significance of coronary lesions.

OBJECTIVE

To evaluate diagnostic accuracy of dipyridamole stress technetium-99 m tetrofosmin, single-photon emission computed tomography as a possible alternative to invasive coronary angiography for detection and follow-up of myocardial ischaemia in patients with Kawasaki disease, and pre- and post-coronary bypass grafting.

PATIENTS AND METHODS

Coronary angiography and single-photon emission computed tomography were performed on 21 patients who were classified into three groups - group I (stenosis), group II (giant aneurysms), and group III (small aneurysms). Of the 21 patients, 16 (groups I and II) patients with myocardial perfusion defects, who underwent coronary bypass grafting, were followed up with single-photon emission computed tomography.

RESULT

In group I, all patients had significant coronary stenosis and 100% of them had perfusion defects in the anterior and septal walls. In group II, all patients had giant aneurysms and 83% of them had inferior and inferolateral perfusion defects. In group III, all patients had small aneurysms and 100% of them had normal perfusion. Pre-coronary bypass grafting myocardial ischaemic defects disappeared in all patients after surgery. Sensitivity, specificity, and accuracy of single-photon emission computed tomography were 94, 100, and 95%, respectively.

CONCLUSION

Technetium-99 m tetrofosmin single-photon emission computed tomography can be applied as an accurate non-invasive diagnostic technique for detecting myocardial perfusion defects with coronary artery lesions, and to show improved or even normalised perfusion of the myocardium in patients after surgical revascularisation.

Identification of an association between genomic hypomethylation of FCGR2A and susceptibility to Kawasaki disease and intravenous immunoglobulin resistance by DNA methylation array

OBJECTIVE

Kawasaki disease (KD) is characterized by systemic vasculitis, and it is the most common acquired heart disease in children. However, the etiology and immunopathogenesis of KD are still unclear. A genome-wide association study (GWAS) identified polymorphisms in CD40, BLK, and FCGR2A as the susceptibility genes for KD. No epigenetic array studies of KD have previously been published. This study was undertaken to investigate differences in DNA methylation in patients with KD as compared to controls.

METHODS

The HumanMethylation27 BeadChip (Illumina) was used to survey the differences in DNA methylation between KD patients and controls. DNA methylation array validation was performed in a separate cohort by pyrosequencing assay and reporter gene assays. Messenger RNA (mRNA) expression was determined, and the association of methylation with response to intravenous immunoglobulin (IVIG) treatment was analyzed.

RESULTS

HumanMethylation27 BeadChip assay showed a 15% difference in methylation of 10 genes between KD patients and controls. The FCGR2A cg24422489 group, which was recently reported to be associated with KD susceptibility in a GWAS, had significant hypomethylation of 15.54% less in the KD group than in the control group. Validation of FCGR2A methylation in another cohort also showed significant hypomethylation in the KD group (5 of 5 CpG sites [P < 0.01]; n = 43 in the KD group and n = 55 in the control group). KD patients with IVIG resistance showed hypomethylation of 5 CpG sites (P < 0.05). FCGR2A mRNA expression was significantly increased in patients in the acute stage of KD compared to controls. Reporter gene assays indicated that the CpG sites of the FCGR2A promoter region were sufficient to modulate gene expression.

CONCLUSION

This is the first study to examine the DNA methylation array in KD and identify a role of hypomethylation of FCGR2A in susceptibility to KD and IVIG resistance.

High-density genotyping of immune loci in Kawasaki disease and IVIG treatment response in European-American case-parent trio study

Kawasaki disease (KD) is a diffuse and acute small-vessel vasculitis observed in children, and has genetic and autoimmune components. We genotyped 112 case-parent trios of European decent (confirmed by ancestry informative markers) using the immunoChip array, and performed association analyses with susceptibility to KD and intravenous immunoglobulin (IVIG) non-response. KD susceptibility was assessed using the transmission disequilibrium test, whereas IVIG non-response was evaluated using multivariable logistic regression analysis. We replicated single-nucleotide polymorphisms (SNPs) in three gene regions (FCGR, CD40/CDH22 and HLA-DQB2/HLA-DOB) that have been previously associated with KD and provide support to other findings of several novel SNPs in genes with a potential pathway in KD pathogenesis. SNP rs838143 in the 3'-untranslated region of the FUT1 gene (2.7 × 10(-5)) and rs9847915 in the intergenic region of LOC730109 | BRD7P2 (6.81 × 10(-7)) were the top hits for KD susceptibility in additive and dominant models, respectively. The top hits for IVIG responsiveness were rs1200332 in the intergenic region of BAZ1A | C14orf19 (1.4 × 10(-4)) and rs4889606 in the intron of the STX1B gene (6.95 × 10(-5)) in additive and dominant models, respectively. Our study suggests that genes and biological pathways involved in autoimmune diseases have an important role in the pathogenesis of KD and IVIG response mechanism.

Intravenous immunoglobulin, pharmacogenomics, and Kawasaki disease

Kawasaki disease (KD) is a systemic vasculitis of unknown etiology and it is therefore worth examining the multifactorial interaction of genes and environmental factors. Targeted genetic association and genome-wide association studies have helped to provide a better understanding of KD from infection to the immune-related response. Findings in the past decade have contributed to a major breakthrough in the genetics of KD, with the identification of several genomic regions linked to the pathogenesis of KD, including ITPKC, CD40, BLK, and FCGR2A. This review focuses on the factors associated with the genetic polymorphisms of KD and the pharmacogenomics of the response to treatment in patients with intravenous immunoglobulin resistance.

Markers of a recent bocavirus infection in children with Kawasaki disease: "a year prospective study"

BACKGROUND

Retrospective studies and case-reports have suggested the possible role of various viruses in the pathogenesis of the Kawasaki disease.

OBJECTIVES

To determine prospectively the incidence of Kawasaki diseases associated with a recent bocavirus infection in the course of a year.

STUDY DESIGN

Thirty-two children with Kawasaki disease were enrolled in a 13 months prospective study to assess the frequency of human bocavirus type 1 infections. Seasonal shedding of virus, markers of recent infection such as viraemia, viral load, and serum interferon alpha were analyzed.

RESULTS

Three of 32 (9%) children had HBoV-DNA in the serum suggesting a recent infection. HBoV-DNA was detected in naso-pharyngeal aspiration of 7/32 (21.8%) children with Kawasaki Disease and six of them (18%) had an increased viral load. No common respiratory viruses were isolated from the 32 patients with the exception of one adenovirus. The seven bocaviruses were identified during the winter-spring season. In addition, 4 of 7 of Kawasaki disease patients shedding bocavirus had detectable interferon alpha in the blood, indicating a possible active or recent viral infection.

CONCLUSIONS

This study shows that a recent bocavirus infection is concomitant with the onset of some cases of Kawasaki disease. Bocavirus may be a cofactor in the pathogenesis of this disease as previously reported for other infectious agents.

Genetic variants of CD209 associated with Kawasaki disease susceptibility

BACKGROUND

Kawasaki disease (KD) is a systemic vasculitis with unknown etiology mainly affecting children in Asian countries. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN, CD209) in humans was showed to trigger an anti-inflammatory cascade and associated with KD susceptibility. This study was conducted to investigate the association between genetic polymorphisms of CD209 and the risk KD.

METHODS

A total of 948 subjects (381 KD and 567 controls) were recruited. Nine tagging SNPs (rs8112310, rs4804800, rs11465421, rs1544766, rs4804801, rs2287886, rs735239, rs735240, rs4804804) were selected for TaqMan allelic discrimination assay. Clinical phenotypes, coronary artery lesions (CAL) and intravenous immunoglobulin (IVIG) treatment outcomes were collected for analysis.

RESULTS

Significant associations were found between CD209 polymorphisms (rs4804800, rs2287886, rs735240) and the risk of KD. Haplotype analysis for CD209 polymorphisms showed that A/A/G haplotype (P = 0.0002, OR = 1.61) and G/A/G haplotype (P = 0.0365, OR = 1.52) had higher risk of KD as compared with G/G/A haplotype in rs2287886/rs735239/rs735240 pairwise allele analysis. There were no significant association in KD with regards to CAL formation and IVIG treatment responses.

CONCLUSION

CD209 polymorphisms were responsible for the susceptibility of KD, but not CAL formation and IVIG treatment responsiveness.

Common carotid artery intima-media thickness is useful for diagnosis of the acute stage of Kawasaki disease

Background

This study aimed to investigate intima-media thickness (IMT) of the common carotid arteries in children with acute Kawasaki disease (KD).

Methods

Between 2009 and 2011, patients fulfilling the criteria for KD, including a fever lasting >5 days, were prospectively enrolled in this study. Laboratory data, echocardiography, and IMT were measured and compared with matched controls.

Results

A total of 70 common carotid IMTs were measured in 35 children. We studied 21 patients aged 3–60 months old with acute KD and 14 febrile patients aged 3–194 months old with acute infection and similar characteristics to those of KD patients. Children with KD had a significantly higher IMT compared with the controls (0.550 ± 0.081 mm vs. 0.483 ± 0.046 mm, P = 0.01).

Conclusions

IMT during the acute stage of KD is increased, suggesting that IMT could be a useful diagnostic tool in the early diagnosis of KD.

Association between Kawasaki disease and autism: a population-based study in Taiwan

Objective: The association between Kawasaki disease and autism has rarely been studied in Asian populations. By using a nationwide Taiwanese population-based claims database, we tested the hypothesis that Kawasaki disease may increase the risk of autism in Taiwan. Materials and Methods: Our study cohort consisted of patients who had received the diagnosis of Kawasaki disease (ICD-9-CM: 446.1) between 1997 and 2005 (N = 563). For a comparison cohort, five age- and gender-matched control patients for every patient in the study cohort were selected using random sampling (N = 2,815). All subjects were tracked for 5 years from the date of cohort entry to identify whether they had developed autism (ICD-9-CM code 299.0) or not. Cox proportional hazard regressions were then performed to evaluate 5-year autism-free survival rates. Results: The main finding of this study was that patients with Kawasaki disease seem to not be at increased risk of developing autism. Of the total patients, four patients developed autism during the 5-year follow-up period, among whom two were Kawasaki disease patients and two were in the comparison cohort. Further, the adjusted hazard ratios (AHR) (AHR: 4.81; 95% confidence interval: 0.68–34.35; P = 0.117) did not show any statistical significance between the Kawasaki disease group and the control group during the 5-year follow-up. Conclusion: Our study indicated that patients with Kawasaki disease are not at increased risk of autism.

Genetic polymorphism of SMAD5 is associated with Kawasaki disease

Mothers against decapentaplegic homolog (SMAD) proteins are intracellular mediators of members of the transforming growth factor-β (TGF-β) superfamily, which are activated by bone morphogenetic proteins (BMPs). On activation, SMAD5 forms heterometric SMAD complexes, which are translated to the nucleus where they regulate gene transcription. TGF-β induces T cell activation and cardiovascular disease, two important features of Kawasaki disease (KD), whereas BMP is associated with coronary artery disease. In this study, we hypothesized that single nucleotide polymorphisms (SNPs) of SMAD5 may be associated with KD and coronary arterial lesions (CALs). Genotyping for 15 SNPs of the SMAD5 gene (rs3764941, rs10085013, rs6596284, rs7356756, rs13179769, rs13166063, rs1109158, rs4585442, rs4146185, rs12719481, rs6865297, rs3206634, rs6871224, rs1057898, and rs7031) was performed by direct sequencing of 105 KD patients and 303 healthy adult controls. We also compared the allele frequencies between a CAL group (n = 31) and a normal coronary group (n = 74). Results showed that among the 15 SNPs, rs3206634 was significantly associated with KD in a recessive model (odds ratio = 2.31, p = 0.019), whereas there was no association between any of the 15 SNPs and CALs. These findings may be used as a risk factors development of KD or for future generations of therapeutic treatments for KD.

Monitoring of the serum proteome in Kawasaki disease patients before and after immunoglobulin therapy

Kawasaki disease (KD) is a systemic vasculitis that mainly affects children younger than 5 years. The causal pathogen is unknown, therefore specific diagnostic biomarkers and therapy are unavailable. High-dose intravenous immunoglobulin (IVIG) is considered as the most effective therapy to reduce the prevalence of coronary artery lesion (CAL) in KD; however, it has side effects. This study aimed to (1) determine whether IVIG therapy is effective at the molecular level; (2) provide the first serum proteomic profile of KD under IVIG therapy; and (3) screen for monitoring biomarker candidates. We extracted serum proteins from samples of healthy individuals and from KD patients before and after IVIG therapy, and employed two-dimensional electrophoresis and MALDI-TOF/TOF mass spectrometry to identify differentially expressed proteins. The identifications were validated by Western blotting. We identified 29 differentially expressed proteins in KD patients and found that IVIG therapy restored most of these proteins to near-normal levels. Tracing the protein levels of single patients before and after IVIG therapy showed that the proteins, especially Transthyretin (TTR), are potential markers for therapeutic monitoring. Functional analyses of these proteins by PANTHER and String suggested that the key influence of KD lay in the immune system, which was targeted by IVIG.

Single-nucleotide polymorphism rs7251246 in ITPKC is associated with susceptibility and coronary artery lesions in Kawasaki disease

Kawasaki disease (KD) is a multi-systemic vasculitis that preferentially affects children. A single nucleotide polymorphism (SNP) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) has been identified to be an important polymorphism in the risk of KD. This study was conducted to comprehensively investigate the associations between all tagging SNPs of ITPKC in the risk of KD in a Taiwanese population. A total of 950 subjects (381 KD patients and 569 controls) were recruited. Seven tagging SNPs (rs11673492, rs7257602, rs7251246, rs890934, rs10420685, rs2607420, rs2290692) were selected for TaqMan allelic discrimination assay. Clinical data of coronary artery lesions (CAL) and aneurysms were collected for analysis. A significant association was found between rs7251246 in ITPKC and CAL formation. Haplotype analysis for ITPKC polymorphisms also confirmed this association in the patients with CAL and aneurysm formation. This is the first study to identify that SNP rs7251246 in ITPKC is associated with the severity of KD.

Clinical characteristics of hemophagocytic lymphohistiocytosis following Kawasaki disease: differentiation from recurrent Kawasaki disease

BACKGROUND

Our aim was to investigate the clinical pattern of hemophagocytic lymphohistiocytosis following Kawasaki disease (HLH-KD), to enable differentiation of HLH from recurrent or refractory KD and facilitate early diagnosis.

METHODS

We performed a nationwide retrospective survey and reviewed the clinical characteristics of patients with HLH-KD, including the interval between KD and HLH, clinical and laboratory findings, treatment responses, and outcomes, and compared them with historical data for both diseases.

RESULTS

Twelve patients with HLH-KD, including 5 previously reported cases, were recruited. The median age was 6.5 years (range, 9 months-14.7 years). Eight patients were male and 4 were female. The median interval between the first episode of KD and the second visit with recurrent fever was 12 days (3-22 days). Of the 12 children, 2 were initially treated with intravenous IgG (IVIG) for recurrent KD when they presented at the hospital with recurrent fever. Eventually, 10 children received chemotherapy under an HLH protocol and 2 received supportive treatment. Two patients died of combined infections during chemotherapy, 1 was lost to follow up, and 9 remain alive. The overall survival rate at 4 years was 81.1% with a median follow up of 45.1 months.

CONCLUSION

A diagnosis of HLH-KD should be considered when symptoms similar to recurrent KD develop within 1 month of the first episode of KD. Our findings will help physicians differentiate between HLH and the recurrent form of KD.

TARC/CCL17 gene polymorphisms and expression associated with susceptibility and coronary artery aneurysm formation in Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is a systemic vasculitis of unknown etiology. Thymus and activation-regulated chemokine/chemokine ligand 17 (TARC/CCL17) is one of the Th2 chemokines and has been suggested as a candidate gene for conferring susceptibility to Th2 associated with allergy diseases. This study examined the correlation between gene polymorphisms and plasma levels of TARC/CCL17 in patients with KD and the outcomes of KD.

METHODS

A total of 381 KD patients and 564 controls were subjected to determination of five tagging single-nucleotide polymorphisms of TARC/CCL17. In addition, plasma TARC/CCL17 levels were measured by enzyme-linked immunosorbent assay.

RESULTS

Polymorphisms of TARC/CCL17 were significantly different between normal children and patients with KD. A allele of rs4784805 has better intravenous immunoglobulin (IVIG) treatment response to KD. Furthermore, plasma TARC/CCL17 levels were higher in KD patients than that in controls before IVIG treatment. After IVIG treatment, plasma TARC/CCL17 levels decreased significantly.

CONCLUSION

This study provides the first evidence supporting the association between TARC/CCL17 polymorphisms, susceptibility of KD, and IVIG responses in KD patients.

FcγR gene copy number in Kawasaki disease and intravenous immunoglobulin treatment response

OBJECTIVE

Kawasaki disease (KD), response to intravenous immunoglobulin (IVIG) therapy, and associated coronary artery disease progression have been associated with genetic polymorphisms in Fc gamma receptor (FcγR) genes. However, it is not known whether the existing gene copy number (GCN) variability relates to KD treatment response, susceptibility, or associated sequelae.

METHODS

The copy number of individuals with KD (n=510) and their family members (n=808) for three variable FcγRs was assessed using pyrosequencing. We performed the transmission disequilibrium test to examine the association of GCN for FcγRs (FcγR2C, FcγR3A, and FcγR3B) with susceptibility and used logistic regression models to determine its association with IVIG treatment outcomes.

RESULTS

FcγR2C and FcγR3B GCN were significantly associated with KD susceptibility. IVIG response was associated with GCN variations of FcγR3B in Whites and FcγR2C in Hispanics, and gene risk score based on single nucleotide polymorphism and GCN in FcγRs were significantly different between IVIG responders and nonresponders among Whites. We found no significant associations between coronary artery disease and any of the FcγR copy numbers.

CONCLUSION

GCN of FcγR2C and FcγR3B influences IVIG treatment response and predisposes individuals to KD, providing potential insights into understanding the mechanism of the FcγR gene family in the IVIG pathway.

Increased risk of atopic dermatitis in preschool children with kawasaki disease: a population-based study in taiwan

Kawasaki disease (KD) is an acute febrile systemic vasculitis and has been reported to be associated with allergic disease. The risk of atopic dermatitis (AD) in preschool children with KD has not been investigated. The study was to determine the longitudinal risk of the development of AD in preschool children with KD. A nationwide 5-year population-based study was performed using data from the National Health Insurance Database in Taiwan between 1999 and 2003. The risk factors for AD were compared between the 2 study groups during the follow-up period using the Cox proportional hazards model. In addition, plasma interleukin (IL)-5 levels were analyzed in normal subjects and KD patients. Among the 1440 subjects included, 21.6% developed AD during the 5-year follow-up period, of which 30.3% and 18.7% belonged to the study cohort and the comparison group, respectively. Children with KD were 1.25 times more likely to have AD than those in controls (P = 0.04). Levels of IL-5 and IgE were significantly higher in KD patients. Children with KD had a higher risk of developing AD during the 5-year follow-up period than the control group. Increased IL-5 and IgE levels may be key factors contributing to the risk of AD.

Clinical manifestations of Kawasaki disease shock syndrome: a case-control study

BACKGROUND

Kawasaki disease shock syndrome (KDSS) is a severe condition related to Kawasaki disease (KD), and sometimes it is difficult to diagnose. This is a case-control study to ascertain the clinical presentations, risk factors, and clinical outcomes of children who had KDSS.

MATERIALS AND METHODS

Children who were hospitalized during 2001-2011 with the diagnosis of KD combined with hypotension, sepsis, or shock were retrospectively reviewed and were defined as case patients. For each case patient, three season-matched patients diagnosed as having KD with normal blood pressure were identified to serve as control patients. Demographic characteristics, clinical presentations, laboratory features, therapies, and outcomes were analyzed.

RESULTS

Nine KDSS patients and 27 control patients were identified. The average age of patients with KDSS was 3.2 ± 3.2 years. Compared with controls, KDSS patients were less likely to have a diagnosis of KD at admission (22.2% vs. 66.7%) and had a higher risk of coronary artery dilatation (77.8% vs. 11.1%). Risk factors for KDSS included higher neutrophil counts and proportions of bands, higher C-reactive protein (CRP), and lower platelet counts. All case patients received aspirin therapy; eight patients received intravenous immunoglobulin therapy, with two receiving more than one course. Seven KDSS patients required fluid resuscitation, and eight patients required vasoactive infusions.

CONCLUSION

Patients with KDSS may have uneven clinical course and may be misdiagnosed in the beginning. They may have more prominent inflammatory markers in the early phase and higher risk of coronary artery dilatation.

Long-term evaluation of endothelial function in Kawasaki disease patients

BACKGROUND

Kawasaki disease is an acute systemic vasculitis. Cardiac complications are frequent and include endothelial dysfunction in patients with coronary anomalies. So far, the presence of endothelial dysfunction in patients with no coronary lesions has not been demonstrated. Peripheral arterial tonometry (Endo-PAT) measures the microvascular function in response to local ischaemia and has been validated in adult population, but its use in children is scarce. Aim To evaluate endothelial dysfunction in children as a long-term complication after Kawasaki disease using Endo-PAT.

METHODS

We evaluated two groups of subjects: (1) Kawasaki disease patients over 11 years of age, diagnosed for >5 years, with no coronary lesions, or any other risk factors for cardiovascular disease; (2) control group of individuals without cardiovascular risk factors. Patients and controls were clinically accessed. Endo-PAT was performed to determine reactive hyperaemia index and augmentation index.

RESULTS

A total of 35 individuals (21 males, age 21 ± 6 years) were evaluated (group 1: 19; controls: 16). Kawasaki disease patients presented significant lower reactive hyperaemia index (1.68 ± 0.49 versus 2.31 ± 0.53; p = 0.001). Augmentation index was similar in both groups (-10 ± 7 versus -11 ± 5; p > 0.005). Most patients with Kawasaki disease disclosed endothelial dysfunction (68%) compared with only 12% in controls.

CONCLUSIONS

Endo-PAT is feasible and reproducible in the child population. Endothelial dysfunction is a frequent long-term complication in patients after Kawasaki disease with normal appearing coronary arteries. However, these results need validation in a larger population.

A replication study for association of ITPKC and CASP3 two-locus analysis in IVIG unresponsiveness and coronary artery lesion in Kawasaki disease

Single-nucleotide polymorphisms (SNPs) in inositol 1,4,5-trisphosphate 3-kinase C (ITPKC, rs28493229) and caspase-3 (CASP3, rs113420705) are associated with susceptibility to KD in Japanese and Taiwanese populations. This study was conducted to investigate the involvement of these 2 SNPs in the risk for intravenous immunoglobulin (IVIG) resistance and coronary artery lesion (CAL) in Taiwanese population. A total of 340 KD patients were subjected to assess by the identification of 2-locus genes model. A combinatorial association between ITPKC (rs28493229) and CASP3 (rs113420705) was found in CAL formation (P = 0.0227, OR: 3.06). KD patients with high-risk genotype had a trend of overrepresentation in IVIG resistance compared with individual SNPs. Our findings suggest the existence of genetic factors affecting patients’ risk for CAL formation and IVIG responsiveness in a Taiwanese population.

Population-based study of the association between urbanization and Kawasaki disease in Taiwan

Background. It is unclear if the prevalence of Kawasaki disease (KD) correlates with the degree of urbanization. We hypothesized that the prevalence of KD is more pronounced in urban versus rural environments. Methods. The National Health Insurance (NHI) program was implemented in Taiwan in 1995 and covers most of the population (>99%). We used the NHI database to investigate the epidemiological features of KD. A total of 115 diagnosed patients with KD from 1997 to 2010 were included, together with 1,150 matched controls without KD. Chi-square analyses were performed to investigate the difference between modern city and rural environments. Results. Of the 1265 sampled subjects (claims data from 1,000,000 random subjects), the mean age of the KD study group and control group was 2.08 ± 1.66 and 2.08 ± 1.64 years, respectively. After matching for age, sex, and same index date, no statistically significant differences in urbanization level and geographical location of the patients' residence were observed. Conclusion. Urbanization did not appear to be an important effect modifier of Kawasaki disease in Taiwan.

Management of acute and refractory Kawasaki disease

Acute Kawasaki disease (KD) is treated with high-dose intravenous immunoglobulin (IVIG), which is proven to decrease the incidence of coronary artery aneurysms from 25% to less than 5%. Aspirin is also given, although the evidence base is less secure. There is increasing evidence for steroid therapy as adjunctive primary therapy with IVIG, especially in Asian children. Approximately 10-30% of patients fail to respond to the initial IVIG and are at increased risk of coronary artery aneurysms. The optimal treatment for IVIG-nonresponsive KD remains controversial. Management options include further dose(s) of IVIG, corticosteroids, TNF-α blockade, cyclosporin A, anti-IL-1 and anti-CD20 therapy. In this article, the authors review the current evidence for treatment of acute KD and discuss options for IVIG nonresponders.

Kawasaki disease and subsequent risk of allergic diseases: a population-based matched cohort study

Background

The risk of allergic diseases among Kawasaki disease (KD) patients relative to the general population is not known. The aim of this study was to perform a population-based cohort study to investigate the risk of allergic diseases among children after KD in Taiwan- a country with the third highest incidence of KD in the world.

Methods

Data were obtained from the Taiwan National Health Insurance Research Database. In total, 253 patients who were 5 years of age or younger and had a first-time hospitalization with a diagnosis of KD between 1997 and 2005 were included as the study cohort and 1,012 non-KD patients matched for age and sex were included as comparison cohort. Multivariate Cox proportional hazard regression model was used to adjust for confounding and to compare the 6-year allergic-free survival rate between these two cohorts.

Results

The incidence rate of allergic diseases (184.66 per 1000 person-year) was significantly higher in the KD cohort than in the control cohort (124.99 per 1000 person-years). After adjusting for potential confounders, the adjusted hazard ratios of asthma and allergic rhinitis were 1.51 (95% confidence interval = 1.17-1.95) and 1.30 (95% confidence interval = 1.04-1.62), respectively.

Conclusion

We conclude that KD patients were at an increased risk for allergic diseases compared with the comparison cohort.

Reaction at the bacillus Calmette--Guérin inoculation site in patients with Kawasaki disease

BACKGROUND

The bacillus Calmette-Guérin (BCG) reaction is not included in the classical clinical criteria for Kawasaki disease (KD). However, a reaction at the BCG inoculation site has been mentioned among the "other clinical findings" that are present in about 30-50% of KD patients. The objective of this study was to investigate the clinical characteristics of KD patients with reactions at the BCG inoculation site.

METHODS

A retrospective study of all patients diagnosed with KD between September 2000 and August 2010 was performed. The clinical presentations, laboratory results, treatment outcomes, and coronary artery abnormalities in the BCG-reactive [BCG(+)] and BCG-nonreactive [BCG(-)] groups were analyzed and compared.

RESULTS

In total, 145 patients with KD diagnosed at our institution were included; 46 (31.7%) had a reaction at the BCG inoculation site. The BCG(+) group was younger than the BCG(-) group. Laboratory results showed higher white blood cell counts, platelet counts, and serum potassium levels, and lower low-density lipoprotein levels in the BCG(+) group. The BCG(+) group had a shorter fever duration before intravenous immunoglobulin treatment and a shorter total fever duration than the BCG(-) group. Multivariable logistic regression analysis showed that the age at diagnosis was the only factor significantly associated with a reaction at the BCG inoculation site in KD patients.

CONCLUSIONS

In countries with a national BCG vaccination program, a reaction at the BCG inoculation site could be a useful and early diagnostic sign of KD among younger patients, especially those younger than 6 months.

Tricuspid regurgitation in acute phase of Kawasaki disease associated with intensive care unit admission

Kawasaki disease (KD) is a systemic vasculitis and primarily affects children <5 years of age. Intensive care unit (ICU) admission is unusual, but there can be associated severe complications in KD patients. This study was conducted to identify risk factors for ICU admission. Retrospectively, we reviewed charts of all children who had a discharge diagnosis of KD from 2001 through 2009. Clinical presentation, laboratory data, and outcome were collected for analysis of the association with ICU admission in KD patients. Multifactor dimensionality reduction (MDR) was used to identify factor interactions. There were 334 KD patients, including 24 patients in ICU admission, included in the analysis. Coronary artery lesions (CALs) and failure of intravenous immunoglobulin (IVIG) treatment were more frequently found in the ICU group (P < 0.0001). Total counts of white blood cells, hemoglobin levels, C-reactive protein, and albumin levels showed significant association with ICU admission (P < 0.05). Moderate tricuspid regurgitation (TR) was found only in the ICU admission group. MDR analyses of factor interactions identified that TR interacted with CAL with a prediction accuracy of 77.78 %. (P = 0.001). Patients with KD who are IVIG resistant and/or who are found to have CALs are at increased risk for ICU admission. Most importantly, moderate TR was significantly found in KD patients only in the ICU group. This may highlight the great value of moderate TR in predicting ICU admission for patients with KD.

Variations in the number of CCL3L1 gene copies and Kawasaki disease in Korean children

High-dose intravenous immunoglobulin (IVIG) therapy is the highly effective and standard treatment for Kawasaki disease (KD). However, ~20 % of KD patients have persistent fever or recurrence of fever after the initial IVIG treatment, which increases the risk for coronary artery lesions (CALs). Furthermore, the mechanism of IVIG resistance in KD patients still is unknown. The number of CC chemokine ligand 3-like 1 (CCL3L1) gene copies is reported to be associated with KD and IVIG resistance in Japanese patients. In addition, the authors observed significant upregulation of the CCL3L1 gene expression after in vitro immunoglobulin treatment in B cell lines derived from KD patients. Therefore, this study of 459 KD patients and 496 healthy control subjects tested whether the number of CCL3L1 gene copies is associated with a risk of KD, CALs, and/or IVIG resistance in Korean KD patients. However, the number of CCL3L1 gene copies was not associated with KD (P = 0.18), CAL formation (P = 0.062), or the IVIG resistance (P = 0.90). Therefore, the results indicate that the number of CCL3L1 gene copies does not have a role in susceptibility to KD or CALs nor with IVIG resistance in Korean KD patients.

Important role of CCR2 in a murine model of coronary vasculitis

Background

Chemokines and their receptors play a role in the innate immune response as well as in the disruption of the balance between pro-inflammatory Th17 cells and regulatory T cells (Treg), underlying the pathogenesis of coronary vasculitis in Kawasaki disease (KD).

Results

Here we show that genetic inactivation of chemokine receptor (CCR)-2 is protective against the induction of aortic and coronary vasculitis following injection of Candida albicans water-soluble cell wall extracts (CAWS). Mechanistically, both T and B cells were required for the induction of vasculitis, a role that was directly modulated by CCR2. CAWS administration promoted mobilization of CCR2-dependent inflammatory monocytes (iMo) from the bone marrow (BM) to the periphery as well as production of IL-6. IL-6 was likely to contribute to the depletion of Treg and expansion of Th17 cells in CAWS-injected Ccr2^+/+ mice, processes that were ameliorated following the genetic inactivation of CCR2.

Conclusion

Collectively, our findings provide novel insights into the role of CCR2 in the pathogenesis of vasculitis as seen in KD and highlight novel therapeutic targets, specifically for individuals resistant to first-line treatments.

Single-nucleotide polymorphism rs2290692 in the 3'UTR of ITPKC associated with susceptibility to Kawasaki disease in a Han Chinese population

Kawasaki disease (KD) is characterized by acute systemic vasculitis and frequently is complicated by coronary artery lesions (CALs). The inositol 1,4,5-trisphosphate 3-kinase C (ITPKC) gene rs28493229 was recently found to be associated with the risk for KD in the Japanese population, suggesting that the ITPKC gene may contribute to KD susceptibility. This study investigated the association of ITPKC polymorphisms with KD in a Han Chinese population. Five ITPKC Single-nucleotide polymorphisms, including rs28493229, were genotyped in 223 unrelated patients who had KD and 318 non-KD control subjects. The allele, genotype, and haplotype frequencies were compared between the patients and the control subjects, between the patients with and those without CALs, and between patients resistant to intravenous immunoglobulin treatment and those responsive to such treatment. Multiple alleles were observed for rs28493229 and rs2290692. No significant differences in the frequencies of the C allele, the CC genotype, or the C carriers of rs28493229 were observed in the comparisons. Interestingly, significantly higher frequencies of the C allele (p < 0.001), the CC genotype (p = 0.001), and the C carriers (p = 0.003) were observed for rs2290692 among the patients than among the control subjects, and similar differences were observed between the patients with and those without CALs. The GC haplotype for rs28493229 and rs2290692 was more common among the patients than among the control subjects. The results indicate that the C allele of the ITPKC gene rs2290692 is linked to a significantly higher risk for KD in the studied population, which provides new evidence to support the importance of the ITPKC gene in the occurrence of KD. More notably, this finding suggests that there may be an unidentified ITPKC polymorphism in strong linkage disequilibrium to rs2290692, significantly affecting susceptibility to KD in the Han population.

DC-SIGN (CD209) promoter -336 A/G (rs4804803) polymorphism associated with susceptibility of Kawasaki disease

Kawasaki disease (KD) is characterized by systemic vasculitis of unknown etiology. High-dose intravenous immunoglobulin (IVIG) is the most effective therapy for KD to reduce the prevalence of coronary artery lesion (CAL) formation. Recently, the α2, 6 sialylated IgG was reported to interact with a lectin receptor, specific intracellular adhesion molecule-3 grabbing nonintegrin homolog-related 1 (SIGN-R1) in mice and dendritic cell-specific intercellular adhesion molecule-3 grabbing nonintegrin (DC-SIGN) in human, and to trigger an anti-inflammatory cascade. This study was conducted to investigate whether the polymorphism of DC-SIGN (CD209) promoter −336 A/G (rs4804803) is responsible for susceptibility and CAL formation in KD patients using Custom TaqMan SNP Genotyping Assays. A total of 521 subjects (278 KD patients and 243 controls) were investigated to identify an SNP of rs4804803, and they were studied and showed a significant association between the genotypes and allele frequency of rs4804803 in control subjects and KD patients (P = 0.004 under the dominant model). However, the promoter variant of DC-SIGN gene was not associated with the occurrence of IVIG resistance, CAL formation in KD. The G allele of DC-SIGN promoter −336 (rs4804803) is a risk allele in the development of KD.