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

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.

General Anesthesia in Early Childhood Significantly Reduces Asthma Incidence and Clinical Visits: A Nationwide Population-Based Cohort Study

Few studies have focused on the consequence of exposure to general anesthesia (GA) in children’s early life with the risk of asthma and disease outcomes. The present study examines the correlation between exposure to GA under three years old and the subsequent course of asthma in a nationwide population-based cohort study. Our cases were acquired from Taiwan’s National Health Insurance Research Database (NHIRD). Children under three years old with either GA exposure or not during in-patient treatment from 1997 to 2008 were included. The study group was age- and sex-matched with a ratio of 1:2 to create the control group for comparison. The cohort included 2261 cases with GA and 4522 cases without GA as a control group. The incidence of asthma onset was significantly reduced in patients with GA exposure under 3 three years old (hazard ratio 0.64 (95% confidence interval 0.57~0.72), p < 0.001). In addition, regardless of whether the asthmatic clinical visits were before or after GA exposure, asthma onset patients before GA exposure have significantly fewer clinical visits than those without GA exposure (both p < 0.001, respectively). Using the Kaplan–Meier method, we also demonstrated that GA exposure was associated with favorable clinical visits in patients with asthma, whether their asthma was onset before GA (p = 0.0102) or after GA exposure (p = 0.0418) compared to non-GA-exposed controls. In the present study, we demonstrated that children with early GA exposure under three years old were at a reduced risk of developing asthma compared to the general population. Furthermore, we first reported that GA exposure significantly reduced clinical visits in patients with asthma regardless of whether their asthma onset was before or after GA exposure. It is indicated that GA exposure at a younger age could have potential clinical benefits for asthma than non-GA-exposed controls.

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.

Expression of Eosinophilic Subtype Markers in Patients with Kawasaki Disease

PURPOSE

Eosinophils may rise to a higher level in the acute phase of Kawasaki disease (KD) both before and after intravenous immunoglobulin (IVIG) therapy. A substantial body of research was carried out on the association between KD and allergic diseases. Eosinophils play an important role in type 2 inflammation. Recent studies have shown that there are two distinct subtypes of eosinophils. In addition to their role in inflammation, lung-resident eosinophils (rEOS) also regulate homeostasis. Inflammatory eosinophils (iEOS) reflect type 2 inflammation in tissues. iEOS were considered the primary eosinophils in non-severe allergic asthma, while rEOS were thought to be the primary eosinophils in severe non-allergic eosinophilic asthma. This case-control study aimed to investigate the marker expression of eosinophilic subtypes in KD patients.

MATERIALS AND METHODS

The marker expressions of eosinophilic subtypes in the leukocytes of patients with KD were evaluated by the recently established KDmarkers online tool, a web server including gene expression data. Finally, the results were validated with a quantitative reverse transcriptase polymerase chain reaction (RT-PCR). We analyzed the mRNA expression levels of SELL and IL10RA in leukocytes from KD patients and febrile children.

RESULTS

Included in our screening tools were transcriptome arrays, which provided clues showing the importance of rEOS, whose role was identified by three genes (lower IL10RA, higher SELL, and SERPINB1 than controls). In contrast, the iEOS representative gene CD101 was not elevated in KD. It was found that the gene IL10RA, a marker of inflammatory eosinophilic leukocytes, was more highly expressed in the leukocytes of KD patients (n = 43) than febrile controls (n = 32), especially those without coronary artery lesions (CAL) (n = 26). Before treatment, SELL expression was higher in leukocytes of CAL patients (CAL, 1.33 ± 0.18, n = 39; non-CAL, 0.87 ± 0.12, n = 55; p = 0.012). SELL was significantly higher after half a year compared to febrile controls.

CONCLUSIONS

To our knowledge, this is the first study to demonstrate that KD patients have increased SELL than febrile controls after 6 months of treatment. We present evidence here that dynamically different eosinophilic involvement exists between KD patients with and without CAL. The role of eosinophilic subtypes in KD patients warrants further investigation.

Long-term health outcomes in young adults after Kawasaki disease

Background

We compared the long-term health of adults with prior Kawasaki disease (KD) to controls and determined whether outcomes varied by coronary artery (CA) status.

Methods

We conducted a prospective cohort study of 258 KD subjects (mean 19 ± 9 years since KD) and 148 age-similar controls who completed extensive health questionnaires. KD subjects were divided into 2 groups, Cohort 1: 109 subjects followed since KD diagnosis at our institution; Cohort 2: 149 KD subjects diagnosed elsewhere.

Results

KD subjects and controls were of similar age at the time of questionnaire completion (p = 0.50). Overall, 128 subjects (including 60 in Cohort 1) reported normal CAs during and after KD. Compared to controls, KD subjects with normal CAs reported several medical conditions with increased prevalence including migraine headaches, shortness of breath, and leg pain with walking, among others. When limited to Cohort 1, KD subjects were significantly more likely to report chest pain (47% vs 16%, p < 0.001) or palpitations (23% vs 10%, p = 0.01) compared to controls. Prevalence of depression was similar (7% vs 5%, p = 0.73).

Conclusions

Despite always having normal CAs in the acute and subacute phases of KD, young adults with a history of KD with normal coronaries were more likely than controls to experience cardiovascular symptoms. These differences could be influenced by anxiety or depression, but report of depression was similar between groups. Whether these health differences reflect a heightened awareness of symptoms among KD subjects, or underlying vascular pathology (i.e. vasospasm, microvascular dysfunction, other) merits further study.

The Long-term Cardiac and Noncardiac Prognosis of Kawasaki Disease: A Systematic Review

CONTEXT

It is uncertain if children with Kawasaki Disease (KD) are at risk for non-cardiac diseases and if children with KD but without coronary artery aneurysms (CAA) are at risk for long-term cardiac complications.

OBJECTIVE

To determine the long-term mortality and prognosis of children after KD.

DATA SOURCES

Medline, Embase, and the Cochrane Central Register.

STUDY SELECTION

Controlled trials and observational studies were included if they included children with KD and reported mortality, major adverse cardiovascular events (MACE), chronic cardiac or other disease over an average follow-up of ≥1 year.

DATA EXTRACTION

Data extracted included sample size, age at diagnosis, the proportion with coronary artery aneurysms (CAA), follow-up duration, and outcome(s).

RESULTS

Seventy-four studies were included. Thirty-six studies reported mortality, 55 reported a cardiac outcome, and 12 reported a noncardiac outcome. Survival ranged from 92% to 99% at 10 years, 85% to 99% at 20 years, and 88% to 94% at 30 years. MACE-free survival, mostly studied in those with CAA, varied from 66% to 91% at 10 years, 29% to 74% at 20 years, and 36% to 96% at 30 years. Seven of 10 studies reported an increased risk in early atherosclerosis. All 6 included studies demonstrated an increased risk in allergic diseases.

LIMITATIONS

Our study may have missed associated chronic comorbidities because short-term studies were excluded. The majority of outcomes were evaluated in East-Asian patients, which may limit generalizability. Studies frequently excluded patients without CAA and did not compare outcomes to a comparison group.

CONCLUSIONS

Studies demonstrate >90% survival up to 30 years follow-up. MACE is observed in children with CAA, but is not well studied in those without CAA.

High Serum Total IgE at Admission Is Associated with Coronary Artery Lesions in Children with Kawasaki Disease

Kawasaki disease (KD) is associated with allergy. As immunoglobulin E (IgE), a key element of allergic reactions, is related with coronary heart disease, we evaluated the serum total IgE levels, and investigated its clinical relevance in 339 children with KD. These patients were classified as high IgE group and normal IgE group according to the reference value of IgE. Serum IgE levels in the high group (279.76 ± 202.54 IU/mL) significantly increased compared with the normal group (5.51 ± 15.79 IU/mL) (p < 0.001). There were also no significant differences in the frequency of major clinical manifestation between the two groups. The number of patients who developed coronary artery lesions (CALs) was significantly higher in the high group (p = 0.004), and the serum levels of IgE were also markedly higher in the KD patients with CALs than in patients without CALs (p = 0.002). High total serum IgE was an independent prognostic for CALs in the multivariate analysis. In conclusion, serum IgE levels may be associated with CALs in children with KD.

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.

A National Population Cohort Study Showed That Exposure to General Anesthesia in Early Childhood Is Associated with an Increase in the Risk of Developmental Delay

This study investigated the relationship between exposure to general anesthesia (GA) and the risk of cognitive and mental disorders. This study has thus investigated the relationships between exposure to GA before the age of 3 and subsequent cognitive and mental disorders in a national-wide research sample. We obtained our subjects from the National Health Insurance Research Database (NHIRD) of Taiwan, which was based on the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Children in the hospital aged less than 3 years old were included if there was GA exposure or not during the period of year 1997 to 2008. Cox proportional hazard regression models adjusted for potential confounding factors were used to estimate the relative magnitude of the risk associated with GA exposure. The cohort contained 2261 subjects with GA and 4522 children without GA as a comparison group. GA exposure group had a higher rate of developmental delay than in the without GA group (hazard ratio 1.46, p < 0.0001). There was no significant difference in the overall incidence of ADHD, autism and intellectual disability between the GA-exposed group and the comparison cohort. In conclusion, this study reported that children exposed to GA early before the age of three had a small association with increased risk of development delay thereafter.

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.

Long-Term Hypermethylation of FcγR2B in Leukocytes of Patients with Kawasaki Disease

The Fc gamma receptor family contains several activating receptors and the only inhibitory receptor, FcγR2B. In this study, we investigated the dynamic methylation change of FcγR2B in different stages of Kawasaki disease (KD). We enrolled a total of 116 participants, which included patients with febrile diseases as controls and KD patients. Whole blood cells of KD patients were collected prior to intravenous immunoglobulin (IVIG) treatment (KD1), three to seven days after IVIG (KD2), three weeks after IVIG treatment (KD3), six months after IVIG (KD4), and one year after IVIG treatment (KD5). In total, 76 KD patients provided samples in every stage. Leukocytes of controls were also recruited. We performed DNA extraction and pyrosequencing. FcγR2B methylation levels were higher in KD3 compared to both the controls and KD1. A significantly higher methylation of FcγR2B was found in KD5 when compared with KD1. FcγR2B methylation levels in the IVIG-resistant group were lower than those in the IVIG-responsive group at KD1-3 (p = 0.004, 0.004, 0.005 respectively). This study is the first to report the dynamic change of FcγR2B methylation and to demonstrate long-term hypermethylation one year after disease onset. Hypomethylation of FcγR2B is associated with IVIG resistance.

Chemical and Biochemical Aspects of Molecular Hydrogen in Treating Kawasaki Disease and COVID-19

Kawasaki disease (KD) is a systemic vasculitis and is the most commonly acquired heart disease among children in many countries, which was first reported 50 years ago in Japan. The 2019 coronavirus disease (COVID-19, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)) has been a pandemic in most of the world since 2020, and since late 2019 in China. Kawasaki-like disease caused by COVID-19 shares some symptoms with KD, referred to as multisystem inflammatory syndrome in children, and has been reported in the United States, Italy, France, England, and other areas of Europe, with an almost 6-10 times or more increase compared with previous years of KD prevalence. Hydrogen gas is a stable and efficient antioxidant, which has a positive effect on oxidative damage, inflammation, cell apoptosis, and abnormal blood vessel inflammation. This review reports the chemical and biochemical aspects of hydrogen gas inhalation in treating KD and COVID-19.

Kawasaki Disease in the Australian Population: An Australian Tertiary Hospital Experience

AIM

To describe the contemporary experience of Kawasaki Disease (KD) in a tertiary paediatric hospital.

METHODS

This was a retrospective analysis of admissions with suspected/confirmed KD to John Hunter Children's Hospital from 1 January 2015 to 31 December 2016, with follow-up. Patients were stratified into classical, incomplete, unlikely and uncertain KD cohorts based on the 2004 American Heart Association (AHA) guidelines.

RESULTS

Forty (40) patients had 45 admissions with suspected KD. Twenty-four (24) patients (60%) had complete and incomplete KD. Twenty-nine per cent (29%) (7/24) were not diagnosed at presentation. Thirty per cent (30%) (12/40) were incompletely assessed according to the AHA pathway. Seventy-one per cent (71%) of KD patients (17/24) were treated with aspirin and intravenous immunoglobulin. The incidence was 22-26 per 100,000 in children less than 5 years during the study period, higher compared to prior data.

CONCLUSION

The diagnosis of KD remains challenging, with some children not diagnosed at the time of initial presentation. The increase in KD incidence is hypothesis generating and requires further investigation.

IgA Levels Are Associated with Coronary Artery Lesions in Kawasaki Disease

Background and Objectives

Kawasaki disease (KD) is an acute systemic vasculitis that affects the coronary arteries. Abnormal immune reactions are thought to contribute to disease pathogenesis. The effect of immunoglobulin (Ig) isotype (IgG, IgA, IgM, and IgE) on inflammatory data and clinical outcomes of patients with KD was examined.

Methods

Ig levels in 241 patients with KD were measured during the acute, subacute, convalescent, and normal phases of the disease.

Results

Compared with reference Ig values, IgG, IgA, and IgM levels were significantly higher in the subacute phase, while IgE levels were elevated in 73.9% (178/241) of patients with KD in all clinical phases. However, high IgE levels were not associated with clinical outcomes, including intravenous immunoglobulin unresponsiveness and coronary artery lesions (CALs). Significantly more CALs were observed in the high IgA group than in the normal IgA group (44.7% vs. 20.8%, respectively; p<0.01). In addition, IgA levels in the acute phase (p=0.038) were 2.2-fold higher, and those in the subacute phase were 1.7-fold higher (p <0.001), in the CAL group than in the non-CAL group. IgA concentrations increased along with the size of the coronary artery aneurysm (p <0.001). Furthermore, there was a strong correlation between IgA levels and CAL size (r=0.435, p<0.001), with a high odds ratio of 2.58 (p=0.022).

Conclusions

High IgA levels in patients with KD are prognostic for the risk of CALs.

Increased Risk of Kawasaki Disease in Infants Born of Mothers With Immune Disorders

Introduction: Genetic susceptibility and immune dysregulation play important roles in the pathogenesis of Kawasaki disease (KD). However, it is still unclear whether KD causes immune disorder later in life or whether inherited susceptibility to immune disorders causes KD. The aim of this study was to elucidate whether inherited immune disease properties from mothers increase the risk of KD from a population-based perspective. Method: Taiwan's National Health Insurance Research Database was the main data source in this study. Parents and children were linked using the Taiwan Maternal and Child Health Database. Patients diagnosed with KD and younger than 18 years from 2004 to 2015 were enrolled as the study population. The control group was randomly selected from individuals without the diagnosis of KD matched by age, index year, sex, and urbanization level at a ratio of 1 to 10. The prevalence of maternal autoimmune and allergic diseases was compared between groups. Results: In total, 7,178 children were found to have been diagnosed with Kawasaki disease. Then 71,780 children matched by index year, gender, and urbanization were randomly selected to serve as the control group. Children born from mothers with asthma and allergic rhinitis had a higher risk of developing KD. Children of mothers with an autoimmune disorder had a significantly increased tendency to develop KD. Maternal numbers of autoimmune disorders showed a dose-dependent relationship with KD incidence. Conclusion: This is the first population-based study to investigate maternal immune diseases and the risk of KD in their children. Children of mothers with immune disorders tend to have a higher risk of KD.

Molecular mechanisms and epidemiology of COVID-19 from an allergist's perspective

The global pandemic caused by the newly described severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused worldwide suffering and death of unimaginable magnitude from coronavirus disease 2019 (COVID-19). The virus is transmitted through aerosol droplets, and causes severe acute respiratory syndrome. SARS-CoV-2 uses the receptor-binding domain of its spike protein S1 to attach to the host angiotensin-converting enzyme 2 receptor in lung and airway cells. Binding requires the help of another host protein, transmembrane protease serine S1 member 2. Several factors likely contribute to the efficient transmission of SARS-CoV-2. The receptor-binding domain of SARS-CoV-2 has a 10- to 20-fold higher receptor-binding capacity compared with previous pandemic coronaviruses. In addition, because asymptomatic persons infected with SARS-CoV-2 have high viral loads in their nasal secretions, they can silently and efficiently spread the disease. PCR-based tests have emerged as the criterion standard for the diagnosis of infection. Caution must be exercised in interpreting antibody-based tests because they have not yet been validated, and may give a false sense of security of being "immune" to SARS-CoV-2. We discuss how the development of some symptoms in allergic rhinitis can serve as clues for new-onset COVID-19. There are mixed reports that asthma is a risk factor for severe COVID-19, possibly due to differences in asthma endotypes. The rapid spread of COVID-19 has focused the efforts of scientists on repurposing existing Food and Drug Administration-approved drugs that inhibit viral entry, endocytosis, genome assembly, translation, and replication. Numerous clinical trials have been launched to identify effective treatments for COVID-19. Initial data from a placebo-controlled study suggest faster time to recovery in patients on remdesivir; it is now being evaluated in additional controlled studies. As discussed in this review, till effective vaccines and treatments emerge, it is important to understand the scientific rationale of pandemic-mitigation strategies such as wearing facemasks and social distancing, and implement them.

Adenovirus infection and subsequent risk of Kawasaki disease: A population-based cohort study

BACKGROUND

The relationship between adenovirus infection and Kawasaki disease (KD) is unclear. The purpose of this study was to determine the relationship between adenovirus infection and KD using a cohort study in Taiwan.

METHODS

We used Taiwan National Health Insurance data (from 2000 to 2008) to conduct a population-based cohort study, analyzing children that was under 18 years of age. In total, 5280 children had adenovirus infection, and 5280 children without adenovirus infection were matched and followed up. Subsequent KD was the major outcome event. The Cox proportional hazards model was used to estimate the hazard ratio (HR) with 95% confidence intervals (CIs) of developing KD associated with adenovirus infection.

RESULTS

There was a significantly higher cumulative incidence of KD in the adenovirus-infected cohort than that in the control cohort (log-rank test, p < 0.001). In the adenovirus-infected cohort, overall incidence of KD was 5.29 times higher than that of the control cohort (adjusted HR 5.29, 95% CI: 2.48-11.3). Increased KD risk was associated with previous adenovirus infection in children aged 3-5 years, in female patients, in those with a low urbanization level, and in those with allergies.

CONCLUSION

An association between previous adenovirus infection and KD was identified in Taiwanese children, but other potential risk factors were not fully analyzed. The relationship between infection and KD requires further study.

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.

Prescribing patterns of coronary artery aneurysm in Taiwan

Background

Coronary artery aneurysm (CAA) is a rare disease, and there are limited data on prescribing patterns for CAA. The aim of our study was to investigate prescribing patterns for CAA in Taiwan via the National Health Insurance Research Database (NHIRD).

Methods

We included all CAA patients in Taiwan from 2005 to 2011. Data from 1 year before and after the CAA diagnosis were used to analyze examinations, comorbidities and prescribing patterns.

Results

A total of 1397 patients diagnosed with CAA were enrolled in our study. Most pediatric patients with CAA were diagnosed with Kawasaki disease (95.7%). In pediatric CAA patients, the utilization rates of aspirin and gamma globulins were 82.9 and 53.6%, respectively, after CAA diagnosis. Among the antithrombotic agents, aspirin was used most commonly, followed by dipyridamole (16.9%), heparin (5.8%) and warfarin (4.6%). In adult CAA patients, common comorbidities included hypertension (63.4%), hyperlipidemia (39.6%), and diabetes mellitus (26.1%). Coronary atherosclerosis was identified in 72.5% of adult patients after CAA diagnosis. Antithrombotic agents, particularly aspirin, clopidogrel and heparin, were prescribed more frequently after CAA diagnosis. Among the prescribed medications, aspirin (75.8%), β-blockers (48.3%), statins (47.6%), metformin (14.4%), sulfonylureas (14.4%) and isosorbide mononitrate (32.9%) were frequently observed in each category.

Conclusions

Kawasaki disease was the main cause of CAA in pediatric patients, and coronary artery disease was the most common comorbidity in adult CAA patients. The most commonly used antithrombic agent after CAA diagnosis was aspirin in both adult and pediatric patients.

Association between maternal age and outcomes in Kawasaki disease patients

BACKGROUND

The etiology of Kawasaki disease (KD) is still unknown; perinatal factors may have role with few studies. This study was aim to survey the perinatal factors and clinical outcome of KD, including coronary artery lesion (CAL) formation and intravenous immunoglobulin (IVIG) treatment response.

METHODS

We enrolled a total of 185 KD patient-caregiver dyads in this study using questionnaires. The questionnaire included two categories: children's characteristics, which consisted of age at disease onset, gender, gestational age at delivery, birth body weight, delivery methods, and breastfeeding status, and caregivers' characteristics, which consisted of parents or not, education levels, maternal age at giving birth, total number of offspring, and family income. We analyzed the association of these factors with CAL formation and IVIG treatment response of KD.

RESULTS

KD patients with CAL formation had a higher maternal age than non-CAL patients (32.49 ± 3.42 vs. 31.01 ± 3.92 years, p = 0.016). We also found that maternal age ≥ 32 years group had a higher rate of having KD patients with CAL (39/81 vs. 24/74, odds ratio 1.935, 95% confidence interval [1.007, 3.718], p = 0.047). The maternal age ≥ 35 years group had a higher rate of having KD patients with IVIG resistance (6/31 vs. 6/116, odds ratio 4.400, 95% confidence interval [1.309, 14.786], p = 0.01). There was no significant difference in either CAL formation or IVIG resistance in KD with regard to patient's age at disease onset, gestational age, birth body weight, delivery methods, breastfeeding, caregiver type, caregivers' education level, total number of offspring, or family income (p > 0.05).

CONCLUSIONS

This study is the first to report that maternal age is significantly associated with CAL formation and IVIG resistance in KD. We hypothesize that a maternal age less than 32 years would benefit KD offspring.

Increased Incidence of Kawasaki Disease in Taiwan in Recent Years: A 15 Years Nationwide Population-Based Cohort Study

Background: Kawasaki disease (KD) is diagnosed in children suffering from fever for more than five days and five clinical characteristic symptoms. The aim of this article was to research the clinical characteristics among KD children in Taiwan in recent years through a population-based cohort study. Materials and Methods: We carried out a nationwide retrospective cohort study by analyzing the data of KD patients (ICD-9-CM code 4461) from Taiwan's National Health Insurance Research Database (NHIRD) during the period of 1996-2011. Results: Among all the insured children in the NHIRD, insurance claims data were reported for 13,260 patients diagnosed with KD, with 8394 (63.30%) subjects being administered IVIG for treatment. Of the patients diagnosed with KD, 94% were under the age of 5 years old, and the majority of cases occurred in May. Furthermore, the incidence of KD more than doubled (28.58-60.08 per 100,000) during this period in Taiwan. Conclusion: We developed a five-based mnemonic device for parents and first-line clinicians to easily use in order to diagnose KD. We also observed an increased incidence of KD in Taiwan during the study period. In addition, we develop a five-based mnemonic device for parents and first-line clinicians in clinical diagnosis of KD can easily remember: Fever> 5 days, 5 clinical criteria, predominantly in children <5 years of age, and peak seasonal clustering in the 5th month, May (April-June) in Taiwan.

Enterovirus Infection and Subsequent Risk of Kawasaki Disease: A Population-based Cohort Study

BACKGROUND

The relationship of enterovirus (EV) infection and Kawasaki disease (KD) is still unclear. The purpose of this study was to conduct a population-based cohort study to determine the relationship between KD and EV infection in Taiwan.

METHODS

A population-based cohort study was conducted to analyze the children file (age < 18 years) of the Taiwan National Health Insurance program between 2000 and 2008. In total, 285,636 children with EV infection and 285,636 children without EV infection were included and followed up. The subsequent KD was the major outcome event.

RESULTS

The cumulative incidence of KD was significantly higher in the EV-infected cohort than in the non-EV-infected cohort (log-rank test, P < 0.001). The overall incidence of KD was 56% higher in the EV-infected cohort than in the non-EV-infected cohort, with an adjusted hazard ratio of 1.56 (95% confidence interval: 1.44-1.69). Stratified analysis showed higher KD risk associated with previous EV infection in children 3-5 years old, in girls, in children living in less urbanization levels, in children with parental low-income occupation, and in children with allergic diseases.

CONCLUSIONS

There is a higher association between KD and previous EV infection in Taiwanese children, especially in those 3-5 years old, with female sex, with less urbanization level, with low-income parental occupation, and with allergy.

The effect of FcγRIIA and FcγRIIB on coronary artery lesion formation and intravenous immunoglobulin treatment responses in children with Kawasaki disease

Previous research has found patients with the FcγRIIIB NA1 variant having increased risk of intravenous immunoglobulin (IVIG) resistance in Kawasaki disease (KD). Our previous studies revealed that elevated FcγRIIA expression correlated with the susceptibility of KD patients. We conducted this research to determine whether and how Fcγ receptors affect the susceptibility, IVIG treatment response, and coronary artery lesions (CAL) of KD patients. The activating FcγRIIA and inhibitory FcγRIIB methylation levels of seven patients with KD and four control subjects were examined using HumanMethylation27 BeadChip. We enrolled a total of 44 KD patients and 10 control subjects with fevers. We performed real-time RT-PCR to determine the FcγRIIA and FcγRIIB expression levels, as well as a luciferase assay of FcγRIIA. We found a considerable increase in methylation of both FcγRIIA and FcγRIIB in KD patients undergoing IVIG treatment. Promoter methylation of FcγRIIA inhibited reporter activity in K562 cells using luciferase assay. The FcγRIIB mRNA expression levels were not found to increase susceptibility, CAL formation, or IVIG resistance. FcγRIIA mRNA expression levels were significantly higher in IVIG-resistant patients than in those that responded to IVIG during the pre-treatment period. Furthermore, the FcγRIIA/IIB mRNA expression ratio was considerably higher in KD patients with CAL than in those without CAL. FcγRIIA and FcγRIIB both demonstrated increased methylation levels in KD patients that underwent IVIG treatment. FcγRIIA expression influenced the IVIG treatment response of KD patients. The FcγRIIA/IIB mRNA expression ratio was greater in KD patients with CAL formation.

Inhaled corticosteroids have a protective effect against lung cancer in female patients with chronic obstructive pulmonary disease: a nationwide population-based cohort study

Whether the use of inhaled corticosteroids (ICS) protects patients with chronic obstructive pulmonary disease (COPD) from lung cancer remains undetermined. In this retrospective nationwide population-based cohort study, we extracted data of 13,686 female COPD patients (ICS users, n = 1,290, ICS non-users, n = 12,396) diagnosed between 1997 and 2009 from the Taiwan's National Health Insurance database. These patients were followed-up until 2011, and lung cancer incidence was determined. Cox regression analysis was used to estimate hazard ratios (HRs) for lung cancer incidence. The time to lung cancer diagnosis was significantly different between ICS users and non-users (10.75 vs. 9.68 years, P < 0.001). Per 100,000 person-years, the lung cancer incidence rate was 235.92 for non-users and 158.67 for users [HR = 0.70 (95% confidence interval {CI}: 0.46-1.09)]. After adjusting for patients' age, income, and comorbidities, a cumulative ICS dose > 39.48 mg was significantly associated with a lower risk of lung cancer [ICS users > 39.48 mg, HR = 0.45 (95% CI: 0.21-0.96)]. Age ≥ 60 years, pneumonia, diabetes mellitus, and hypertension decreased lung cancer risk, whereas pulmonary tuberculosis increased the risk. Our results suggest that ICS have a potential role in lung cancer prevention among female COPD patients.

Correlation of symptomatic enterovirus infection and later risk of allergic diseases via a population-based cohort study

Infants who are exposed to the rhinovirus or respiratory syncytial virus are at a higher risk of subsequently developing wheezing or asthma. This study aims to determine whether preschoolers with a history of symptomatic enterovirus infection are at an increased risk of developing allergic diseases or not.We used data from the Taiwan National Health Insurance Research Database from 1999 to 2006 for this nationwide population-based cohort study. The subsequent risks for allergic diseases, which included asthma (International Classification of Diseases [ICD]-9: 493.X), allergic rhinitis (AR; ICD-9 CM code 477.X), and atopic dermatitis (AD; ICD-9-CM code 691.X), were compared between herpangina (ICD-9: 074.0) and hand, foot, and mouth disease (HFMD; ICD-9: 074.3) throughout the follow-up period using the Cox proportional hazards model.In this database, 12,016 neonates were born between January 1999 and December 1999. Among them, we further evaluated 8337 subjects; 3267 children infected with either herpangina or HFMD served as the study cohort, and the other 5070 children made up the comparison cohort. Children in the herpangina group had a higher risk of developing AR and AD, with adjusted hazard ratios of 1.15 (1.02-1.30, 95% CI) and 1.38 (1.17-1.63. 95% CI), respectively, while children suffered from HFMD had decreased risks of asthma, with an adjusted hazard ratio of 0.76 (0.63-0.93, 95% CI).Children who previously suffered from herpangina experienced an increased risk of subsequently developing AD and AR. Meanwhile, children who had suffered from HFMD experienced a decrease in the subsequent occurrence of asthma compared to the general population.

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.

[Changes in peripheral blood T helper 9 cells and interleukin-9 in children in the acute stage of Kawasaki disease]

OBJECTIVE

To investigate the changes in the expression levels of peripheral blood T helper 9 (Th9) cells and cytokine interleukin-9 (IL-9) in children in the acute stage of Kawasaki disease (KD) and their clinical significance.

METHODS

A total of 45 children in the acute stage of KD who were treated from April 2014 to July 2015 were enrolled, and the children were followed up in the recovery stage. Another 45 healthy children who underwent physical examination were enrolled as the control group. Flow cytometry was used to measure the percentage of peripheral blood Th9 cells, and ELISA was used to measure the serum level of IL-9.

RESULTS

The children in the acute stage of KD showed a significantly higher percentage of Th9 cells and a significantly higher serum level of IL-9 compared with those in the recovery stage and the control group (P<0.05). The percentage of Th9 cells and serum level of IL-9 showed no significant differences between the children in the recovery stage and those in the control group (P>0.05). In the acute stage, the percentage of Th9 cells was positively correlated with the levels of IL-9, C-reactive protein (CRP), procalcitonin (PCT), erythrocyte sedimentation rate (ESR), platelet count (PLT), and globulin (r=0.624, 0.324, 0.402, 0.382, 0.467, and 0.386 respectively, all P<0.05), but negatively correlated with serum albumin (r=-0.306, P<0.05). The serum level of IL-9 was positively correlated with the levels of CRP, PCT, ESR, PLT, and globulin (r=0.365, 0.456, 0.403, 0.423, and 0.453 respectively, all P<0.05), but negatively correlated with serum albumin (r=-0.343, P<0.05).

CONCLUSIONS

The children in the acute stage of KD show significant increases in the percentage of peripheral Th9 cells and serum cytokine IL-9 level, which return to normal in the recovery stage. In the acute stage of KD, the expression levels of Th9 and IL-9 are closely correlated with laboratory markers. The results suggest that Th9 cells and IL-9 play important roles in the pathogenesis and outcome of KD.

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.

Inhaled corticosteroids can reduce osteoporosis in female patients with COPD

Background

Whether the use of inhaled corticosteroids (ICSs) in patients with COPD can protect from osteoporosis remains undetermined. The aim of this study is to assess the incidence of osteoporosis in patients with COPD with ICS use and without.

Patients and methods

This is a retrospective cohort and population-based study in which we extracted newly diagnosed female patients with COPD between 1997 and 2009 from Taiwan’s National Health Insurance (TNHI) database between 1996 and 2011 (International Classification of Diseases, Ninth Revision – Clinical Modification [ICD-9-CM] 491, 492, 496). The patients with COPD were defined by the presence of two or more diagnostic codes for COPD within 12 months on either inpatient or outpatient service claims submitted to TNHI. Patients were excluded if they were younger than 40 years or if osteoporosis had been diagnosed prior to the diagnosis of COPD and cases of asthma (ICD-9 CM code 493.X) before the index date. These enrolled patients were followed up till 2011, and the incidence of osteoporosis was determined. The Cox proportional hazards regression model was also used to estimate hazard ratios (HRs) for incidences of lung cancer.

Results

Totally, 10,723 patients with COPD, including ICS users (n=812) and nonusers (n=9,911), were enrolled. The incidence rate of osteoporosis per 100,000 person years is 4,395 in nonusers and 2,709 in ICS users (HR: 0.73, 95% confidence interval [CI]: 0.63–084). The higher ICS dose is associated with lower risk of osteoporosis (0 mg to ≤20 mg, HR: 0.84, 95% CI: 0.69–1.04; >20 mg to ≤60 mg, HR: 0.78, 95% CI: 0.59–1.04; and >60 mg, HR: 0.72, 95% CI: 0.55–0.96; P for trend =0.0023) after adjusting for age, income, and medications. The cumulative osteoporosis probability significantly decreased among the ICS users when compared with the nonusers (P<0.001).

Conclusion

Female patients with COPD using ICS have a dose–response protective effect for osteoporosis.

General anesthesia exposure in early life reduces the risk of allergic diseases: A nationwide population-based cohort study

General anesthesia (GA) has been used for second line treatment strategy for status asthmaticus in pediatric patients. The association between GA in children and risk of followed-up allergic diseases is unclear. This study aims to assess the risk of allergic diseases after GA in children.We did a nationwide retrospective cohort study by analyzing data from the National Health Insurance Research Database (NHIRD) in Taiwan. The subsequent risks for allergic diseases, including asthma (ICD-9: 493.X), allergic rhinitis (AR; ICD-9 CM code 477.X), and atopic dermatitis (AD; ICD-9-CM code 691.X), were compared between exposure to GA and none before 1 year of age throughout the follow-up period using the Cox proportional hazards model.Insurance claims data for 32,742 children younger than 1 year old from all insured children in the NHIRD. Of those, 2358 subjects were exposed to GA; 414 and 1944 children exposed to mask and intubation ventilation, respectively, served as the study cohort, whereas the remaining 30,384 children made up the comparison cohort. Children in the GA group were at a lower risk of developing asthma, AR and AD, with adjusted hazard ratios of 0.67 (0.62-0.72, 95%CI), 0.72 (0.68-0.77, 95%CI), 0.60 (0.56-0.64, 95%CI), respectively.Children who were exposed to GA in early life before 1 year of age had reduced risk of subsequently developing allergic diseases such as asthma, AD, and AR, when compared with general population.

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.

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.

Genetic variants in PLCB4/PLCB1 as susceptibility loci for coronary artery aneurysm formation in Kawasaki disease in Han Chinese in Taiwan

Kawasaki disease (KD) is an acute, inflammatory, and self-limited vasculitis affecting infants and young children. Coronary artery aneurysm (CAA) formation is the major complication of KD and the leading cause of acquired cardiovascular disease among children. To identify susceptible loci that might predispose patients with KD to CAA formation, a genome-wide association screen was performed in a Taiwanese KD cohort. Patients with both KD and CAA had longer fever duration and delayed intravenous immunoglobulin treatment time. After adjusting for these factors, 100 susceptibility loci were identified. Four genes were identified from a single cluster of 35 using the Ingenuity Pathway Analysis (IPA) Knowledge Base. Silencing KCNQ5, PLCB1, PLCB4, and PLCL1 inhibited the effect of lipopolysaccharide-induced endothelial cell inflammation with varying degrees of proinflammatory cytokine expression. PLCB1 showed the most significant inhibition. Endothelial cell inflammation was also inhibited by using a phospholipase C (PLC) inhibitor. The single nucleotide polymorphism rs6140791 was identified between PLCB4 and PLCB1. Plasma PLC levels were higher in patients with KD and CC+CG rs6140791genotypes, and these genotypes were more prevalent in patients with KD who also had CAA. Our results suggest that polymorphism of the PLCB4/B1 genes might be involved in the CAA pathogenesis of KD.

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.

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.

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.