Tendency toward atopy in Kawasaki disease

Six-year trend of subsequent allergic diseases following Kawasaki disease and its clinical implications: A population-based matched cohort study of 34,712 patients

BACKGROUND

It has been suggested that allergic diseases may increase after Kawasaki disease (KD). We aimed to analyze the temporal patterns of allergic disease incidence after KD.

METHODS

A nationwide population-based matched cohort study was conducted using data from the Korean National Health Insurance claims database. Patients aged <5 years diagnosed with KD and their 1:3 propensity score-matched controls were included. Three cohorts were established: Cohort A, patients with allergies; Cohort B, patients without allergies; and Cohort C, patients without allergies, but excluding patients with birth history and underlying medical conditions. Cumulative incidence rates (%) and associated hospital visits for allergic rhinitis, atopic dermatitis, urticaria, and asthma were compared between the cases and controls during the 6-year follow-up period.

RESULTS

The study population comprised 8678 patients diagnosed with KD and 26,034 controls. In Cohort A, although initially, there were intergroup differences in the number of hospital visits for certain allergic diseases, these differences were inconsistent and varied depending on the type of allergic disease. Over time, the differences narrowed, and by the sixth year, the gap had decreased significantly. In Cohorts B and C, the initial incidence rates of the four allergic diseases and associated hospital visits were lower in patients with KD as compared to controls. However, with a faster rate of increase, the incidence rates and number of hospital visits eventually surpassed those of the controls.

CONCLUSIONS

The pattern of delayed increase in cumulative incidence rates and hospital visits for allergic diseases after KD suggests the possibility of a shared genetic or immunologic susceptibility between KD and allergic diseases, which becomes evident over time, rather than a direct influence of KD resulting in allergic diseases.

Association of Kawasaki disease with urbanization level and family characteristics in Taiwan: A nested case-control study using national-level data

Kawasaki disease (KD) is an inflammatory vasculitis disorder of unknown etiology. It is a rare but fatal disease and the leading cause of acquired coronary heart disease in children under the age of 5 years. We examined the association of KD with the demographics of family members, parents' characteristics, and perinatal factors in Taiwanese children. This nested case-control study used data from Taiwan's Health and Welfare Data Science Center and initially included children born in Taiwan between January 1, 2006, and December 31, 2015 (n = 1,939,449); the children were observed for KD development before the age of 5 years (n = 7870). The control group consisted of children without KD who were matched with each KD case by sex and birth date at a ratio of 8:1. The odds ratio (ORs) of the aforementioned associations were estimated using conditional logistic regression. The risk of KD decreased in children with younger parents [<25 years; younger maternal age, OR = 0.72, 95% confidence interval (CI), 0.66-0.79; younger paternal age, OR = 0.68, 95% CI, 0.59-0.78], lower socioeconomic status, more than 2 siblings (OR = 0.80, 95% CI, 0.73-0.89), and siblings with a history of KD (OR = 4.39, 95% CI, 3.29-5.86). Children living in suburban (OR = 0.95, 95% CI, 0.90-1.00) and rural (OR = 0.81, 95%CI, 0.74-0.90) areas exhibited a lower risk of KD than children living in urban areas. In conclusion, a higher incidence rate of KD was observed in children aged <5 years who had an urban lifestyle, had siblings with KD, were born to older mothers, and belonged to high-income and smaller families. Parental allergic or autoimmune diseases were not associated with the risk of KD.

Comparison of Previous Infectious and Allergic Diseases Between Patients with Kawasaki Disease and Propensity Score-matched Controls: A Nationwide Cohort Study

OBJECTIVE

To determine whether previous infectious and allergic diseases are associated with the development of Kawasaki disease in children.

STUDY DESIGN

This nationwide, population-based, case-control study used data from the Korean National Health Insurance claims database. The entire cohort consisted of patients younger than 5 years of age diagnosed with Kawasaki disease and 1:5 propensity score-matched controls from 2013 to 2019. The epidemiologic features and previous infectious or allergic diseases between the 2 groups were compared, and potential factors that could influence the association were identified.

RESULTS

In total, 32 964 patients diagnosed with Kawasaki disease and 164 820 controls were included. Patients with Kawasaki disease had more frequent diagnoses of previous sepsis or bacteremia (OR 1.41), acute pyelonephritis (OR 1.10), and otitis media (OR 1.24). In addition, Kawasaki disease was associated with previous diagnoses of atopic dermatitis (OR 1.05), urticaria (OR 1.08), and asthma (OR 1.05). The association between previous infectious or allergic diagnoses and Kawasaki disease was more prominent in younger patients (<2 years). However, intravenous immunoglobulin resistance, sex, and region of residence were not significant factors that consistently influenced the association between previous infectious or allergic diseases and Kawasaki disease.

CONCLUSIONS

Despite the increased rates of previous infectious and allergic diseases in patients with Kawasaki disease compared with controls, the association between allergic diseases and Kawasaki disease was weaker in our cohort than in previous studies.

Increased Risk of Asthma and Allergic Rhinitis in Patients With a Past History of Kawasaki Disease: A Systematic Review and Meta-Analyses

Background: Allergic diseases are frequently observed in children with Kawasaki disease (KD). However, the evidence supporting the association between KD and allergies has been conflicting. The objective of the current study is to examine the association between KD and allergic diseases. Methods: We conducted an electronic search using PubMed, Embase, and the Cochrane through 24 July 2021. The inclusion criteria consisted of studies that examined the prevalence of allergic diseases in children with a previous diagnosis of KD and in a comparison group. We pooled studies by using a random effects model. The effects of KD on the subsequent risk of allergic diseases were expressed as odds ratio (OR) with 95% confidence intervals (CI). Results: We included a total of four studies that assessed the effect of KD on asthma, allergic rhinitis, and atopic dermatitis vs. non-KD children (KD individuals for asthma, four studies, n = 8,474; allergic rhinitis, four studies, n = 8,474; atopic dermatitis, three studies, n = 8,330). The overall prevalence of asthma, allergic rhinitis, and atopic dermatitis was 9.12, 27.63, and 6.55% among patients with previous KD. The meta-analysis showed a significantly increased risk of asthma (OR:1.437, CI: 1.067-1.937) and allergic rhinitis (OR: 1.726, CI: 1.291-2.307) in patients with KD, compared with the control groups. However, patients with KD did not have a significantly different level of risk of atopic dermatitis (OR: 1.243, 95% CI: 0.857-1.802). Conclusion: This meta-analysis supports that individuals with KD are more likely to have asthma and allergic rhinitis compared to controls.

Hygiene Hypothesis as the Etiology of Kawasaki Disease: Dysregulation of Early B Cell Development

Kawasaki disease (KD) is an acute systemic vasculitis that occurs predominantly in children under 5 years of age. Despite much study, the etiology of KD remains unknown. However, epidemiological and immunological data support the hygiene hypothesis as a possible etiology. It is thought that more sterile or clean modern living environments due to increased use of sanitizing agents, antibiotics, and formula feeding result in a lack of immunological challenges, leading to defective or dysregulated B cell development, accompanied by low IgG and high IgE levels. A lack of B cell immunity may increase sensitivity to unknown environmental triggers that are nonpathogenic in healthy individuals. Genetic studies of KD show that all of the KD susceptibility genes identified by genome-wide association studies are involved in B cell development and function, particularly in early B cell development (from the pro-B to pre-B cell stage). The fact that intravenous immunoglobulin is an effective therapy for KD supports this hypothesis. In this review, I discuss clinical, epidemiological, immunological, and genetic studies showing that the etiopathogenesis of KD in infants and toddlers can be explained by the hygiene hypothesis, and particularly by defects or dysregulation during early B cell development.

Is there any association between asthma and Kawasaki disease? A systematic review and meta-analysis

OBJECTIVE

Shared immune factors are involved in the pathogenesis of asthma and Kawasaki disease (KD). Consequently, several observational studies have explored an association between KD and asthma. This systematic review and meta-analysis aimed to explore the association between KD and asthma.

METHODS

PubMed and Embase databases were searched for cross-sectional, case-control and cohort studies that investigated the association between KD and asthma. The first author, publication year, study type, sample size, and participant demographics were retrieved. The association between KD and asthma was expressed by the odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Eleven studies were eligible in the systematic review. The crude ORs (cORs) were extracted from 11 studies, and seven of them also provided adjusted ORs (aORs). The cORs between KD and asthma was 1.53 (95% CI, 1.29-1.81). After adjustment for some confounding factors (age, sex, region), asthma also had an association with KD (aOR, 1.08; 95% CI, 1.00-1.17). The subgroup analyses showed the study design and study location to influence between-study heterogeneity. Analyses of aOR values revealed that asthma onset before KD onset does not appear to increase KD prevalence, whereas people suffering from KD could increase the prevalence of developing asthma.

CONCLUSION

Our meta-analysis suggested a possible association between preceding KD and asthma onset, but care must be taken when interpreting this result. Prospective cohort studies are needed to assess a causal relationship between these two diseases.

Kawasaki Disease and Allergic Diseases

Background: Kawasaki disease (KD) is an inflammatory disorder with an unknown etiology. It is the leading cause of acquired heart disease, which leads to coronary vasculitis among children. Studies of frequent manifestation of allergic diseases in children with KD have been the subject of mounting clinical interest. However, evidence supporting the association between KD and allergies has yet to be systematically reviewed. Methods: In this article, we reviewed current literature regarding the association between KD and allergic diseases. References for this review were identified through searches of PubMed, Cochrane, and Embase through the end of August 2020. Results: The results of the analyses of immune repertoire, clinical, and epidemiological studies have indicated some of the characteristics of infectious disease for KD. Although some allergic disorders, such as asthma, may be exacerbated by viral infections, allergies are typically caused by an allergen that triggers an immune response, with the potential involvement of type 2 inflammation and immune disturbances leading to tissue remodeling in genetically susceptible hosts. The effect of intravenous immunoglobulin is multi-faceted and results in a decrease in activating Fc gamma receptor IIA and an increase in anti-inflammatory eosinophils. The findings from this review demonstrate that children who have suffered from KD are more likely to have allergic rhinitis than the general population and their siblings, a condition that lasts until the age of 17. When followed up as teenagers and adults, children with KD are more likely to develop urticaria. Conclusions: This review supports that allergic diseases, such as allergic rhinitis, have been demonstrated to increase following KD. Therefore, the importance of allergic diseases in patients with KD should be emphasized in long-term care. Interventions that include strategies for managing allergies in children with KD would be beneficial.

Lower CMV and EBV Exposure in Children With Kawasaki Disease Suggests an Under-Challenged Immune System

Background: Kawasaki Disease (KD) is a pediatric vasculitis of which the pathogenesis is unclear. The hypothesis is that genetically pre-disposed children develop KD when they encounter a pathogen which remains most often unidentified or pathogen derived factors. Since age is a dominant factor, prior immune status in children could influence their reactivity and hence the acquisition of KD. We hypothesized that systemic immune responses early in life could protect against developing KD. With this study we tested whether the incidence of previous systemic cytomegalovirus (CMV) or Epstein-Barr virus (EBV) infection is lower in children with KD compared to healthy age-matched controls. Methods and Results: We compared 86 KD patients with an age-matched control group regarding CMV and EBV VCA IgG measurements (taken before or 9 months after IVIG treatment). We found that both CMV and EBV had an almost 2-fold lower seroprevalence in the KD population than in the control group. Conclusions: We suggest that an under-challenged immune system causes an altered immune reactivity which may affect the response to a pathological trigger causing KD in susceptible children.

A low-frequency IL4R locus variant in Japanese patients with intravenous immunoglobulin therapy-unresponsive Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is a systemic vasculitis which may be associated with coronary artery aneurysms. A notable risk factor for the development of coronary artery aneurysms is resistance to intravenous immunoglobulin (IVIG) therapy, which comprises standard treatment for the acute phase of KD. The cause of IVIG resistance in KD is largely unknown; however, the contribution of genetic factors, especially variants in immune-related genes, has been suspected.

METHODS

To explore genetic variants related to IVIG-unresponsiveness, we designated KD patients who did not respond to both first and second courses of IVIG therapy as IVIG-unresponsive patients. Using genomic DNA from 30 IVIG-unresponsive KD patients, we performed pooled genome sequencing targeting 39 immune-related cytokine receptor genes.

RESULTS

The single nucleotide variant (SNV), rs563535954 (located in the IL4R locus), was concentrated in IVIG-unresponsive KD patients. Individual genotyping showed that the minor allele of rs563535954 was present in 4/33 patients with IVIG-unresponsive KD, compared with 20/1063 individuals in the Japanese genome variation database (odds ratio = 7.19, 95% confidence interval 2.43-21.47). Furthermore, the minor allele of rs563535954 was absent in 42 KD patients who responded to IVIG treatment (P = 0.0337), indicating that a low-frequency variant, rs563535954, is associated with IVIG-unresponsiveness in KD patients. Although rs563535954 is located in the 3'-untranslated region of IL4R, there was no alternation in IL4R expression associated with the mior allele of rs563535954. However, IVIG-unresponsive patients that exhibited the minor allele of rs563535954 tended to be classified into the low-risk group (based on previously reported risk scores) for prediction of IVIG-resistance. Therefore, IVIG-unresponsiveness associated with the minor allele of rs563535954 might differ from IVIG-unresponsiveness associated with previous risk factors used to evaluate IVIG-unresponsiveness in KD.

CONCLUSION

These findings suggest that the SNV rs563535954 could serve as a predictive indicator of IVIG-unresponsiveness, thereby improving the sensitivity of risk scoring systems, and may aid in prevention of coronary artery lesions in KD patients.

Suppressive influence of seasonal influenza epidemic on Kawasaki disease onset

  Kawasaki disease (KD) is an acute systemic vasculitis presenting as an infantile febrile disease. In Japan, the widespread cedar plantation commenced in 1945 has been correlated with the increased incidences of both KD and allergic rhinitis (pollinosis) since the early 1960s. We previously showed that KD was a pollen-induced, delayed-type hypersensitivity that displays biphasic peaks in both summer and winter. KD incidences decrease suddenly around February, particularly after influenza epidemics. Here we investigated the reason for a drastic decrease in KD onsets directly before spring pollen release following rapid increase after autumn pollen release leading to the biphasic pattern. We separately analyzed weekly incidences of KD and influenza in Tokyo (1987-2010) and Kanagawa (1991-2002). Repeated measures for the analysis of variance followed by Bonferroni's multiple comparison tests were performed to compare KD incidence over 3 consecutive weeks, including the weeks when the mean KD prevalence showed the steepest decrease. Next, the week with peak influenza incidence was reset for each year. KD incidence over 3 consecutive weeks, including the new origin week (adjusted week 0), was similarly analyzed. In Tokyo and Kanagawa, KD incidence significantly decreased only after resetting the influenza peak time. These findings suggested that influenza epidemics suppressed KD onset.

Atopic Predilection among Kawasaki Disease Patients: A Cross-Sectional Study of 1,187,757 Teenagers

BACKGROUND

Kawasaki disease (KD) is an acute, systemic vasculitis in children, with an etiology that is not completely understood. It is assumed that the development of KD is mediated by an immunologic response. Several reports from East Asia have found a higher prevalence of atopic diseases among patients with KD, but a large-scale study of a non-Asian population regarding this correlation is still lacking. The purpose of this article was to achieve this goal.

METHODS

We conducted a cross-sectional, large-scale study to estimate the correlation of KD with allergic diseases. The medical history of 1,187,757 Israeli teenagers (aged 16-20 years during the years 1998-2013) was retrieved. The study population was divided into 3 groups according to a past history of noncomplicated and complicated KD and a control group. The prevalence of allergic diseases among these groups was further investigated.

RESULTS

The prevalence of atopic diseases in the 3 study groups was presented (asthma in 11.4, 8.1 and 3.5%, respectively; angioedema/urticaria in 7.1, 0 and 0.46%, respectively; allergic rhinitis in 20, 12.1 and 6.7%, respectively). In noncomplicated KD, a statistically significant link to asthma [odds ratio (OR) 2.4; p = 0.048] and a borderline significant link to allergic rhinitis (OR 1.9; p = 0.06) were found. In KD complicated with cardiac disease, statistically significant links were found for all the allergic conditions, asthma (OR 3.5; p = 0.003), allergic rhinitis (OR 3.5; p < 0.001) and angioedema/urticaria (OR 16.48; p < 0.001).

CONCLUSION

KD is associated with allergic diseases. This association increases with the severity of the disease.

T-Helper Cytokine Profiles in Patients with Kawasaki Disease

Background and Objectives

Kawasaki disease is an acute systemic vasculitis of which pathogenesis suspected is caused by immune dysregulation. The goal of this study is to evaluate the activation pattern of T helper cell type 1 (Th1) and T helper cell type 2 (Th2) in patients with Kawasaki disease.

Subjects and Methods

Prospective study of 60 patients (male 36, female 24) with diagnosis of Kawasaki disease were enrolled. One hundred and eighty blood samples from these patients were collected according to the different clinical stages {before initial intravenous immunoglobulin (IVIG), 5 days after initial IVIG, 2 months after initial IVIG}. The plasma level of Th1 cytokines; interferon-gamma (IFN-γ) & interleukin (IL)-2 and Th2 cytokines; IL-4 & IL-10 were measured by enzyme-liked immunosorbent assay.

Results

In all patients, the plasma level of Th1 cytokines (IFN-γ, IL-2) and Th2 cytokines (IL-4 and IL-10) were markedly elevated during the acute stage of Kawasaki disease. Since then, the plasma level of all these cytokines decreased significantly along with the process of clinical stages. Regardless of the existence of coronary artery lesion or no response to initial IVIG treatment, there were no significant differences between them.

Conclusion

These data suggest that both Th1 and Th2 cells may be activated simultaneously during the acute stage of Kawasaki disease. Further studies are therefore required to establish the difference of activation pattern of T helper cells between Kawasaki disease and other inflammatory diseases.

IL-31 associated with coronary artery lesion formation in Kawasaki disease

BACKGROUND

Kawasaki disease (KD) is known to be associated with T help (Th) 2 reaction and subsequently allergic diseases. Interleukin-31 (IL-31) has also been reported to be involved in Th2 mediated diseases such as allergic diseases. However, the role of IL-31 in KD has not been previously reported. The aim of this study is to investigate whether IL-31 is associated with KD and its clinical outcome.

MATERIAL

A total of 78 KD patients who met the criteria of KD were enrolled in this study as well as 20 age-matched controls. Plasma samples were conducted to measure IL-31 before intravenous immunoglobulin (IVIG) treatment (KD1), within 3 days after IVIG treatment (KD2) and at least 3 weeks after IVIG treatment (KD3) by utilizing enzyme-linked immunosorbent assay (ELISA).

RESULT

Our findings showed that IL-31 expression was higher in KD patients after IVIG treatment significantly (KD2>KD1: 1265.0±199.3 vs. 840.2±152.5 pg/ml, p<0.0001). Further analysis revealed that IL-31 level was significantly higher in KD patients with coronary artery lesion (CAL) (656.6±139.5 vs. 1373.0±422.0 pg/ml, p = 0.04) before IVIG treatment (KD1). There were no significant differences between the IVIG resistance and IVIG responsiveness groups.

CONCLUSION

IL-31 was increased after IVIG treatment in patients with KD and was significantly associated with CAL formation. The results from this study may help to identify a novel risk factor for predicting KD and CAL formation.

A combination of cross correlation and trend analyses reveals that Kawasaki disease is a pollen-induced delayed-type hyper-sensitivity disease

Based on ecological analyses we proposed in 2003 the relation of Kawasaki Disease (KD) onset causing acute febrile systemic vasculitis, and pollen exposure. This study was aimed at investigating the correlation between pollen release and the change in the numbers of KD patients from 1991 to 2002 in Kanagawa, Japan. Short-term changes in the number of KD patients and medium- to long-term trends were analyzed separately. Short-term changes in the number of KD patients showed a significant positive cross correlation (CC) with 9- to 10-month delay following pollen releases, and a smaller but significant CC with 3- to 4-month delay. Further, a temporal relationship revealed by positive CC distribution showed that pollen release preceded KD development, suggesting that pollen release leads to KD development. A trend in patient numbers was fitted by an exponential curve with the time constant of 0.005494. We hypothesized that the trend was caused by the cumulative effects of pollen exposure for elapsed months on patients who may develop KD. By comparing the time constants of fitted exponential curve for each pollen accumulation period with 0.005494, the exposure period was estimated to be 21.4 months, which explains why approximately 50% of patients developed KD within 24 months from birth.

Increased risk of Kawasaki disease in children with common allergic diseases

PURPOSE

Growing evidence reveals a link between Kawasaki disease (KD) and allergic diseases. This population-based case-control study is to investigate the onset of allergic diseases in children and the associated risks of KD.

METHODS

From 1996 to 2008, 2748 children with KD and 10,656 randomly selected controls were enrolled. Odds ratios of KD were calculated for the association with pre-existing allergic diseases.

RESULTS

The children with a single allergic disease had an increased risk of KD, with adjusted odds ratios of having KD of 1.82 for urticaria (95% confidence interval [CI], 1.54-2.14), 1.44 for allergic rhinitis (95% CI, 1.23-1.70), and 1.22 for atopic dermatitis (95% CI, 1.06-1.39). The adjusted odds ratios increased with the number of concurrent allergic diseases, from 1.61 (95% CI, 1.43-1.82) for those with only one allergic disease to 1.71 (95% CI, 1.48-1.98) for those with at least two allergic diseases. The children who made two or more medical visits for associated allergic diseases per year had an increased risk of KD.

CONCLUSIONS

Children with onset of allergic diseases were at increased risk for KD, and the increased risk was associated with the cumulative effect of concurrent allergic diseases and frequency of seeking medical care.

Atopic diathesis in patients with Kawasaki disease

OBJECTIVE

To determine the association between Kawasaki disease (KD) and atopic diathesis (atopic dermatitis [AD], allergic rhinitis, and asthma) in children younger than 5 years of age.

STUDY DESIGN

In this nationwide study, we aimed to analyze the association and temporal relationship between KD and atopic diathesis. Data were obtained from the National Health Insurance Research Database of Taiwan from 1997 to 2010. In total, 200 patients with KD younger than 5 years of age and 800 age- and sex-matched control subjects were enrolled.

RESULTS

In the whole study population, an increased risk of any concomitant atopic diseases was observed in patients with KD (OR 1.61, 95% CI 1.15-2.26). The risk of AD was increased in male patients between 1 and 5 years of age (OR 3.02, 95% CI 1.22-7.50). More than 60% of the patients developed atopic diseases after the diagnosis of KD.

CONCLUSION

There appears to be an association between KD and risk of AD. Most of the atopic diseases occurred after the episode of KD.

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.

Echocardiographic alterations in a child with cow's milk allergy: a case report

Introduction

Cow’s milk allergy is the most frequent food allergy in Europe and western countries and shows a wide spectrum of clinical features, including atopic dermatitis and gastrointestinal disease. To the best of our knowledge, this report is the first to describe Kawasaki disease-like clinical features and echocardiographic alterations which resolved after a cow’s milk-free diet.

Case presentation

We report a case of a 9-month-old Caucasian girl with atopic dermatitis who developed clinical features commonly present in Kawasaki disease (erythematous skin rash, non-exudative conjunctivitis, fissured lips and neck lymph nodes), together with mild echocardiographic alterations (perivascular brightness, pericardial effusion) in the absence of fever. These features resolved within 2 weeks after the beginning of a cow’s milk-free diet.

Conclusion

Kawasaki disease has recently been considered a possible risk factor for subsequent allergic disease secondary to immune dysfunction. This case report suggests that the immune-related alterations which are commonly present in allergic patients could be similar to the antigen-related immune response in Kawasaki disease and thus could lead to similar clinical features.

Hospitalisation with infection, asthma and allergy in Kawasaki disease patients and their families: genealogical analysis using linked population data

BACKGROUND

Kawasaki disease results from an abnormal immunological response to one or more infectious triggers. We hypothesised that heritable differences in immune responses in Kawasaki disease-affected children and their families would result in different epidemiological patterns of other immune-related conditions. We investigated whether hospitalisation for infection and asthma/allergy were different in Kawasaki disease-affected children and their relatives.

METHODS/MAJOR FINDINGS

We used Western Australian population-linked health data from live births (1970-2006) to compare patterns of hospital admissions in Kawasaki disease cases, age- and sex-matched controls, and their relatives. There were 295 Kawasaki disease cases and 598 age- and sex-matched controls, with 1,636 and 3,780 relatives, respectively. Compared to controls, cases were more likely to have been admitted at least once with an infection (cases, 150 admissions (50.8%) vs controls, 210 admissions (35.1%); odds ratio (OR) = 1.9, 95% confidence interval (CI) 1.4-2.6, P = 7.2×10⁻⁶), and with asthma/allergy (cases, 49 admissions (16.6%) vs controls, 42 admissions (7.0%); OR = 2.6, 95% CI 1.7-4.2, P = 1.3×10⁻⁵). Cases also had more admissions per person with infection (cases, median 2 admissions, 95% CI 1-5, vs controls, median 1 admission, 95% CI 1-4, P = 1.09×10⁻⁵). The risk of admission with infection was higher in the first degree relatives of Kawasaki disease cases compared to those of controls, but the differences were not significant.

CONCLUSION

Differences in the immune phenotype of children who develop Kawasaki disease may influence the severity of other immune-related conditions, with some similar patterns observed in relatives. These data suggest the influence of shared heritable factors in these families.

The effect of Kawasaki disease on childhood allergies - a sibling control study

OBJECTIVE

Kawasaki disease (KD) is a multisystem inflammatory vasculitis of childhood, with widespread T-helper cell type 1 immune activation. We hypothesize that children who suffered from KD will have a lower risk of developing allergic diseases.

STUDY DESIGN

This was a cross-sectional study, recruiting children with a history of KD, together with well sibling controls. All children underwent the standardized core ISAAC questionnaire for allergy, physical examination and skin prick test evaluation. McNemar's test was employed to evaluate the effect of Kawasaki disease on allergy. Multivariable analysis based on mixed-effects logistic regression model was used to adjust for potential confounding effect of age and gender.

RESULTS

One hundred and eighty-six children (93 KD sibling pairs) completed the above evaluation. Allergic rhinitis was more common in patients with KD (crude OR 2.40; 95% CI 1.11-5.62, p=0.024) when compared with controls. The effect was further intensified after accounting for the potential confounding effect of age and gender (adjusted OR=2.90; 95% CI 1.27-6.60). Children in whom KD occurred beyond the age of 12 months had more allergic rhinitis (crude OR 4.00, 95% CI 1.29-16.44, p=0.012), 'any' allergies (crude OR 3.75, 95% CI 1.19-15.52, p=0.019) and Blomia tropicalis sensitization (crude OR 2.57, 95% CI 1.02-7.28, p=0.043) when compared with their sibling controls. Interestingly, children in whom KD course resulted in no coronary artery abnormalities have more allergic rhinitis (crude OR 8.50, 95% CI 2.02-75.85, p=0.003) and 'any' allergies (crude OR 5.00, 95% CI 1.41-26.94, p=0.011), when compared with their sibling controls.

CONCLUSION

Kawasaki disease may be a risk factor for subsequent allergic diseases. We postulate that KD occurs more frequently in children at risk of immune disequilibrium, with an abnormal inflammatory response initially, and subsequently more allergic manifestations.

Recurrent fever syndromes in patients after recovery from Kawasaki syndrome

The recurrence of fever in a child with a history of Kawasaki syndrome (KS) poses a dilemma for clinicians who must consider the possibility of recurrent KS. In this report we present the cases of 4 patients who presented with classical symptoms of KS, were successfully treated with intravenous immunoglobulin, and later experienced a reappearance of inflammatory symptoms in a pattern consistent with a recurrent fever syndrome. The association of these syndromes within the same patient suggests that some patients may have a genetic propensity toward altered immune responses and autoinflammatory syndromes. We propose that these 2 syndromes exist within a family of febrile disorders related to innate immune dysregulation.

Vascular endothelial growth factor gene haplotypes in Kawasaki disease

OBJECTIVE

To investigate whether common genetic variants in the vascular endothelial growth factor (VEGF) gene are associated with Kawasaki disease (KD) and the subsequent development of coronary artery lesions.

METHODS

Common genetic variants in the VEGF gene were analyzed in an association study in a Dutch cohort of 170 KD patients and 300 healthy Dutch Caucasian controls. Genotyping was done with 5'-nuclease TaqMan assays and 3'-hybridization-triggered fluorescence minor groove binder Eclipse assays.

RESULTS

An association with susceptibility to KD was observed with 2 of the 6 single-nucleotide polymorphisms analyzed in VEGF: -2594 A>C (rs699947) and the 236 bp 3' of STP C>T (rs3025039). Also for an 18-bp deletion in the promoter of VEGF a significant difference in the genotype and allele frequencies was observed between the KD patients and the controls. The haplotype CGCC (based on rs699947, rs2010963, rs25648, and rs3025039) was significantly associated with the development of KD (hap score 3.8; P = 0.0002). VEGF plasma levels were significantly higher in patients with the early phase of KD than in the healthy controls, and there was a trend toward higher VEGF plasma levels in KD patients with the -2594 CC and 236 bp 3' of STP CC genotypes.

CONCLUSION

Our results suggest that polymorphisms of the VEGF gene may play a role in the pathogenesis of KD.

Family-based association analysis implicates IL-4 in susceptibility to Kawasaki disease

Several compelling lines of evidence suggest an important influence of genetic variation in susceptibility to Kawasaki disease (KD), an acute vasculitis that causes coronary artery aneurysms in children. We performed a family-based genotyping study to test for association between KD and 58 genes involved in cardiovascular disease and inflammation. By analysis of a cohort of 209 KD trios using the transmission disequilibrium test, we documented the asymmetric transmission of five alleles including the interleukin-4 (IL-4) C(-589)T allele (P=0.03). Asymmetric transmission of the IL-4 C(-589)T was replicated in a second, independent cohort of 60 trios (P=0.05, combined P=0.002). Haplotypes of alleles in IL-4, colony-stimulating factor 2 (CSF2), IL-13, and transcription factor 7 (TCF7), all located in the interleukin gene cluster on 5q31, were also asymmetrically transmitted. The reported associations of KD with atopic dermatitis and allergy, elevated serum IgE levels, eosinophilia, and increased circulating numbers of monocyte/macrophages expressing the low-affinity IgE receptor (FCepsilonR2) may be related to effects of IL-4. Thus, the largest family-based genotyping study of KD patients to date suggests that genetic variation in the IL-4 gene, or regions linked to IL-4, plays an important role in KD pathogenesis and disease susceptibility.

Kawasaki disease: infection, immunity and genetics

Kawasaki disease is an acute multisystem vasculitic syndrome of unknown etiology occurring mostly in infants and children younger than 5 years of age. In developed countries, Kawasaki disease is currently the leading cause of acquired heart diseases in children. However, it is still a mysterious disease. In this article, we reviewed and summarized from the aspects based on infection agents, host immune dysregulation and genetic background intended to establish a feasible infection-immunogenetic pathogenesis for this mysterious disease and also provided the rational strategy to explore optimal treatment of this disease.

The diagnosis and management of Kawasaki disease

Kawasaki disease (KD) is a systemic vasculitis of childhood with a predilection for the coronary arteries. It is the predominant cause of paediatric acquired heart disease in developed countries. The aetiology of KD remains unknown and consequently there is no diagnostic test. The diagnosis is made using a constellation of clinical criteria that in isolation have poor sensitivity and specificity. Early treatment prevents overt coronary artery damage in the majority of children. The long-term effects of childhood KD on later cardiovascular health remain unknown. A recent study showed that treatment of KD in Australia is suboptimal, with late diagnosis occurring in approximately half of the cases and an unacceptably high incidence of acute cardiac involvement. These guidelines highlight the difficulties in the diagnosis of KD and offer some clues that may assist early recognition of this important paediatric disease. They also detail current treatment recommendations and the evidence on which they are based. Increased awareness of the epidemiology and spectrum of the clinical presentation of KD is essential for early recognition and optimal management.

Bacterial superantigens and inflammatory skin diseases

Bacteria seem to play an important role in the induction and maintenance of inflammatory skin diseases such as psoriasis and atopic dermatitis. Toxins from bacteria including Streptococcus and Staphylococcus aureus, have been shown to function as a new type of allergen termed 'superantigen'. Superantigens bypass the normal control of T-cell activation and activate all T-cell clones bearing certain types of variable chain on the T-cell receptor: this leads to vigorous T-cell activation and cytokine release. These bacterial superantigens may be involved in induction and aggravation of inflammatory skin diseases. Guttate psoriasis is often preceded by a streptococcal throat infection and T cells specific for streptococcal superantigens have been identified in the skin of patients. The skin of patients with atopic dermatitis is often colonized with superantigen-releasing Staph. aureus, and application of a staphylococcal superantigen to human skin induces an eczematoid reaction.