Angiogenesis in fatal acute Kawasaki disease coronary artery and myocardium

Autoptic Findings in Cases of Sudden Death Due to Kawasaki Disease

Kawasaki disease (KD) is the second-most-common childhood vasculitis, and its etiology is still unknown today. Even though the acute illness is usually self-limiting, sometimes, it can generate complications, such as coronary artery aneurysms (CAA), acute myocardial infarction (AMI), heart failure, or arrhythmias, and can rarely cause sudden or unexpected deaths. We present a review of the literature, which collects autoptic and histopathological data relating to many of the cases of these deaths. On the basis of the titles and abstracts, we selected 54 scientific publications for a total of 117 cases. Among them, as expected, the majority of the deaths were due to AMI (41.03%), arrhythmia (8.55%), acute coronary syndrome (8.55%), and CAA rupture (11.97%), involving mostly 20-year-olds or younger individuls (69.23%). This is not surprising since the CAs are the most involved arteries. Gross autoptic and histopathological findings are reported in the paper. Our work revealed that, when compared with the incidence of KD, only a few cases suffered from sudden death, underwent an autoptic examination, and were then described in the literature. We suggest that researchers should perform autopsies to gain a better understanding of the molecular pathways involved in KD so as to propose further innovative therapeutic protocols or implement more appropriate prevention schemes.

Case Report: Structural Changes in the Coronary Vessel Wall in a Patient With Incomplete Kawasaki Disease

BACKGROUND

Kawasaki disease (KD) is an acute systemic vasculitis of infants and young children that affects medium-sized vessels. Conventional cardiac imaging techniques, such as cardiac catheterization, are useful for characterizing the coronary arterial lesion (CAL) size and luminal diameter of the diseased coronary artery segment in patients with KD, but there are limitations to the visualization of the detailed vascular anatomy. Optical coherence tomography (OCT) is a high-resolution intracoronary arterial imaging modality that can distinguish the three layers of the coronary arterial wall. Several studies have reported coronary artery wall abnormalities in KD patients with coronary arterial aneurysm or regressed aneurysm. However, there have been no reports on changes in the coronary artery wall in cases of incomplete KD without CAL.

CASE PRESENTATION

We herein report an 11-year-old girl with a history of incomplete KD without coronary arterial aneurysms. She had been diagnosed with perimembranous ventricular septal defect (VSD) after birth and had experienced incomplete KD at 1 year old. During her hospitalization for KD, she did not receive intravenous immunoglobulin (IVIG), because she did not meet the Harada score or criteria for treatment in patients with incomplete KD established by the American Heart Association. No dilatation or coronary artery aneurysm were observed on transthoracic echocardiography in the acute or follow-up period. At 11 years old, she received cardiac catheterization and coronary angiography (CAG) for the evaluation of a VSD and follow-up of KD. CAG demonstrated no aneurysm, dilatation, or significant stenosis of the coronary arteries. We performed an OCT study, which revealed the presence of intimal thickening, disruption of the media, and neovascularization in the left anterior descending artery.

CONCLUSION

OCT demonstrates the structural changes of CA even in the patient with incomplete KD who have not been treated with IVIG.

IL-1-dependent electrophysiological changes and cardiac neural remodeling in a mouse model of Kawasaki disease vasculitis

Kawasaki disease (KD) is the leading cause of acquired heart disease in children. In addition to coronary artery abnormalities, aneurysms and myocarditis, acute KD is also associated with echocardiogram (ECG) abnormalities in 40-80% of patients. Here, we show that these ECG changes are recapitulated in the Lactobacillus casei cell wall extract (LCWE)-induced KD vasculitis mouse model. LCWE-injected mice developed elevated heart rate and decreased R wave amplitude, with significant differences in prolonged ventricular repolarization. LCWE-injected mice developed cardiac ganglion inflammation, that may affect the impulse-conducting system in the myocardium. Furthermore, serum nerve growth factor (NGF) was significantly elevated in LCWE-injected mice, similar to children with KD vasculitis, associated with increased neural remodeling of the myocardium. ECG abnormalities were prevented by blocking interleukin (IL)-1 signaling with anakinra, and the increase in serum NGF and cardiac neural remodeling were similarly blocked in Il1r1-/- mice and in wild-type mice treated with anakinra. Thus, similar to clinical KD, the LCWE-induced KD vasculitis mouse model also exhibits electrophysiological abnormalities and cardiac neuronal remodeling, and these changes can be prevented by blocking IL-1 signaling. These data support the acceleration of anti-IL-1 therapy trials to benefit KD patients.

Difference Between Persistent Aneurysm, Regressed Aneurysm, and Coronary Dilation in Kawasaki Disease: An Optical Coherence Tomography Study

BACKGROUND

Coronary artery (CA) aneurysms are a serious complication of Kawasaki disease (KD). Conventional imaging techniques often described segments with regressed aneurysms as normal, whereas studies have shown significant endothelial dysfunction.

METHODS

KD patients with aneurysms scheduled for routine coronary angiography underwent optical coherence tomography (OCT) imaging between 2013 and 2016. Microstructural coronary changes were compared between normal CA segments and those with dilation, regressed aneurysms, and persistent aneurysms.

RESULTS

OCT was performed on 33 patients aged 12.0 ± 5.4 years, 8.5 ± 5.4 years after KD diagnosis. Of the 79 segments analyzed, 25 had persistent aneurysms, 22 regressed aneurysms, 11 CA dilation, and 21 no CA involvement. Intimal thickness was 489 ± 173 μm, 304 ± 158 μm, 102 ± 68 μm, and 63 ± 29 μm, respectively (P < 0.001). There was a linear correlation between the maximum aneurysm size and the intimal thickness, as well as coronary dimension at the time of OCT. Fibrosis (54 segments, 68%) and cellular infiltration (22 segments, 28%) were found more often in segments with CA involvement, but also those without (P = 0.01; P = 0.02). Destruction of the media (34 segments, 43%), calcifications (6 segments, 8%), neovascularization (18 segments, 23%), and white thrombi (8 segments, 10%) were found almost exclusively in segments with a history of aneurysms.

CONCLUSIONS

Intimal hyperplasia, fibrosis, and cellular infiltration were found in all categories of CA involvement, whereas calcification, destruction of the media, neovascularization, and white thrombi were found essentially only in segments with saccular or fusiform aneurysms. Prospective studies with outcome correlations are needed to see if this is associated with an increased risk of late adverse events.

Disruption of vascular homeostasis in patients with Kawasaki disease: involvement of vascular endothelial growth factor and angiopoietins

OBJECTIVE

In Kawasaki disease (KD), a pediatric vasculitis of medium-sized arteries, the coronary arteries are most commonly affected. Angiopoietins and vascular endothelial growth factor (VEGF) play an important role in maintaining vascular homeostasis. Recently, we identified ANGPT1 and VEGFA as susceptibility loci for KD. This study was undertaken to fine-map these associations and to gain further insight into their role in this vasculitis of unknown etiology to further the search for improved diagnostic and therapeutic options.

METHODS

A total of 292 single-nucleotide polymorphisms (SNPs) located in VEGF and ANGPT and their receptors were genotyped in 574 families, including 462 trios. For replication, 123 cases and 171 controls were genotyped.

RESULTS

A significant association with KD susceptibility was observed with 5 SNPs in the ANGPT1 gene (most significantly associated SNP +265037 C>T; Pcombined=2.3×10(-7) ) and 2 SNPs in VEGFA (most significantly associated SNP rs3025039; Pcombined=2.5×10(-4) ). Both ANGPT1 +265037 C>T and VEGFA rs3025039 are located in 3' regulatory regions at putative transcription factor binding sites. We observed significantly down-regulated transcript levels of angiopoietin 1 (Ang-1) in patients with acute KD compared to patients with convalescent KD. In patients with acute KD, high serum protein levels of VEGF and Ang-2 were observed compared to patients with convalescent KD and to both controls with and controls without fever. Immunohistochemistry demonstrated VEGF and angiopoietin expression in the coronary artery wall in autopsy tissue.

CONCLUSION

Our data support the hypothesis that dysregulation of VEGF and angiopoietins contributes to the disruption of vascular homeostasis in KD.

Pathogenesis and management of Kawasaki disease

Kawasaki disease (KD) is an acute systemic inflammatory illness of young children that can result in coronary artery aneurysms, myocardial infarction and sudden death in previously healthy children. Clinical and epidemiologic features support an infectious cause, but the etiology remains unknown four decades after KD was first identified by Tomisaku Kawasaki. Finding the cause of KD is a pediatric research priority. We review the unique immunopathology of KD and describe the current treatment. New research has led to identification of viral-like cytoplasmic inclusion bodies in acute KD tissues; this finding could lead to identification of the elusive etiologic agent and result in significant advances in KD diagnosis and treatment. Current management of acute KD is based upon prospective, multicenter treatment trials of intravenous immunoglobulin (IVIG) with high-dose aspirin. Optimal therapy is 2 g/kg IVIG with high-dose aspirin as soon as possible after diagnosis during the acute febrile phase of illness, followed by low-dose aspirin until follow-up echocardiograms indicate a lack of coronary abnormalities. The addition of one dose of intravenous pulse steroid has not been shown to be beneficial. For the 10-15% of patients with refractory KD, few controlled data are available. Options include repeat IVIG (our preference), a 3-day course of intravenous pulse methylprednisolone, or infliximab (Remicade). Patients with mild-to-moderate coronary abnormalities should receive an antiplatelet agent such as low-dose aspirin (3-5 mg/kg/day) or clopidogrel (1 mg/kg/day up to 75 mg), and those with giant (approximately 8 mm diameter) or multiple coronary aneurysms should receive an antiplatelet agent with an anticoagulant such as warfarin or low-molecular-weight heparin. Acute coronary obstruction requires acute thrombolytic therapy with a surgical or percutaneous interventional procedure.

Transcript abundance patterns in Kawasaki disease patients with intravenous immunoglobulin resistance

Intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD) patients comprise at least 20% of treated patients and are at high risk for coronary artery abnormalities. If identified early in the course of the disease, such patients may benefit from additional anti-inflammatory therapy. The aim of this study was to compare the transcript abundance between IVIG resistant and -responsive KD patients, to identify biomarkers that might differentiate between these two groups and to generate new targets for therapies in IVIG resistant KD patients. We compared the transcript abundance profiles of whole-blood RNA on Agilent arrays from acute and convalescent KD subjects and age-similar, healthy controls. KD subjects were stratified as IVIG resistant or -responsive based on response to initial IVIG therapy. Transcript abundance was higher for IL-1 pathway genes (IL-1 receptor, interleukin receptor associated kinase, p38 mitogen-activated protein kinase), and MMP-8. These findings point to candidate biomarkers that may predict IVIG resistance in acute KD patients. The results also underscore the importance of the IL-1 pathway as a mediator of inflammation in KD and suggest that IL-1 or its receptor may be reasonable targets for therapy, particularly for IVIG resistant patients.

Epidemiologic features of Kawasaki disease in Japan: results of the 2007-2008 nationwide survey

BACKGROUND

The most recent epidemiologic features of Kawasaki disease (KD) are unknown.

METHODS

The 20th nationwide survey of KD was conducted in 2009, and included patients treated for the disease in 2007 and 2008. Hospitals specializing in pediatrics, and hospitals with pediatric departments and 100 or more beds, were asked to report all patients with KD during the 2 survey years.

RESULTS

From a total of 1540 departments and hospitals, 23,337 patients (11 581 in 2007 and 11 756 in 2008) were reported: 13,523 boys and 9814 girls. The annual incidence rates were 215.3 and 218.6 per 100,000 children aged 0-4 years in 2007 and 2008, respectively. These were the highest annual KD incidence rates ever recorded in Japan. The monthly number of patients peaked during the winter months; smaller increases were noted in the summer months. The age-specific incidence rate showed a monomodal distribution with a peak at age 9-11 months. The prevalences of both cardiac lesions during the acute phase of the disease and cardiac sequelae were higher among infants and older age groups.

CONCLUSIONS

The incidence rate and number of patients with KD in Japan continue to increase.

Interleukin-18 gene 105A/C genetic polymorphism is associated with the susceptibility of Kawasaki disease

Interleukin-18 (IL-18)-656T/G, -607A/C, and -137C/G promoter polymorphisms had been reported associated with Kawasaki disease (KD). An IL-18 genetic A/C polymorphism at coding position 105 (rs549908) has been linked with asthma, rheumatoid, and systemic lupus erythematosus. We tested a hypothesis that the IL-18 105A/C genetic polymorphism confers KD susceptibility. Study participants were Taiwanese KD patients and a healthy control group. Our data indicated that the frequency of C allele was significantly higher in the patient group (13.9%) than in the control group (2.7%; P<0.0001, odds ratio [OR]=5.93; 95% confidence interval [CI]=2.57-13.73). Therefore, persons with the C allele may have higher risk of developing KD. In addition, compared with the haplotype frequencies between case and control groups, the KD patients with TACC haplotype appeared to be a significant "at-risk" haplotype compared with other haplotypes (OR: 4.62, 95% CI: 1.71-12.43; P=0.001). KD patient with the TAGA haplotype appeared to be a significant "protective" haplotype compared with other haplotypes (OR: 0.51, 95% CI:0.29-0.89; P=0.017). Our results suggest that 105A/C polymorphism and the haplotypes in IL-18 gene are associated with the risk of KD in Taiwanese population.

Vascular endothelial growth factor, left ventricular dysfunction and mortality in hemodialysis patients

OBJECTIVES

Vascular endothelial growth factor induces nitric oxide-dependent angiogenic effects and participates in the inflammatory response. This cytokine is over-expressed in the myocardium in experimental models of pressure overload and renal mass ablation, and vascular endothelial growth factor is increased in end-stage renal disease. We investigated the relationship between vascular endothelial growth factor, left ventricular function (by midwall fractional shortening) and mortality in a prospective cohort study in 228 hemodialysis patients.

RESULTS

Serum vascular endothelial growth factor concentration was associated directly with interleukin-6 and tumor necrosis factor-alpha (P < 0.01) and inversely with albumin (P = 0.007) but was independent of the endogenous inhibitor of nitric oxide synthesis, asymmetric dimethylarginine. Vascular endothelial growth factor was inversely related with midwall fractional shortening (P = 0.002) and predicted mortality (P = 0.02). In multivariate analyses testing the involvement of this angiogenic cytokine in left ventricular dysfunction and death, these links remained substantially unmodified after adjustment for Framingham risk factors, risk factors peculiar to end-stage renal disease (Hb, Ca, P) and previous cardiovascular complications. However, these links became weaker and not significant when biomarkers of inflammation and asymmetric dimethylarginine were sequentially introduced into the multivariate models. In crude and adjusted analyses, left ventricular function was lowest in patients who displayed both high vascular endothelial growth factor and high asymmetric dimethylarginine, intermediate in patients with either high vascular endothelial growth factor or high asymmetric dimethylarginine and highest in those with low asymmetric dimethylarginine and low vascular endothelial growth factor (P = 0.001).

CONCLUSION

Vascular endothelial growth factor is associated with left ventricular systolic dysfunction and mortality in hemodialysis patients. Vascular endothelial growth factor appears to be in the pathway whereby inflammation and nitric oxide inhibition lead to cardiomyopathy and death in hemodialysis patients.

Decreased expression of pigment epithelium derived factor (PEDF), an inhibitor of angiogenesis, in placentas of unexplained stillbirths

Normal placental vascular development depends upon the complex interactions between angiogenic inducers and inhibitors within the placenta. Alterations within the placental microenvironment can promote an imbalance in angiogenic mediators which may be associated with adverse perinatal outcomes. The purpose of this study was to investigate the placentas of infants with unexplained stillbirth as compared to live-born infants and to determine whether alterations in angiogenic inducer vascular endothelial growth factor (VEGF) or inhibitor pigment epithelium-derived factor (PEDF) are associated with altered angiogenesis, vascular remodeling and stillbirth. Placentas of 22 unexplained stillbirths and 44 age-matched live-born controls were scored for microvascular density (MVD), vasculopathy and microvascular permeability. A subset was scored for expression of angiogenic inducer VEGF and inhibitor pigment epithelium-derived factor. Stillborn placentas demonstrated higher MVD than controls (mean+SD: 116.6+/-46.3 v. 60.8+/-13.5, respectively, p<0.001). Vasculopathy was present in 10/22 (45%) stillbirths compared to 0/44 (0%) controls (p<0.001); increased vascular permeability was present in 15/22 (68%) cases and 5/44 (11%) controls (p<0.001). PEDF expression was significantly lower in stillborn placentas (1.7+/-0.3) than live-born controls (3.6+/-0.8, p<0.01) while VEGF expression was similar (3.3+/-0.7 v. 3.7+/-0.4, respectively, p>0.05). In conclusion, we found that unexplained stillbirth is associated with loss of angiogenic inhibitor PEDF, vasculopathy and heightened angiogenesis in the placenta.

Epidemiologic features of Kawasaki disease in Japan: results from the nationwide survey in 2005-2006

BACKGROUND

The most recent epidemiologic features of Kawasaki disease are unknown.

METHODS

The 19th nationwide survey of the disease was conducted in 2007, targeting patients who were affected by this disease in 2005 and 2006. All pediatric departments in hospitals with 100 or more beds and pediatric hospitals were asked to report all Kawasaki disease patients during the 2 survey years.

RESULTS

From 1543 departments and hospitals, a total of 20475 patients (10041 in 2005 and 10434 in 2006) were reported. There were 11892 male patients and 8583 female patients. The average annual incidence rate was 184.6 per 100000 children aged 0-4 years. The number of patients and the incidence rate have increased significantly during the past 12 years. The age-specific incidence rate was distributed monomodally with a peak at 6-8 months of age. The prevalence of cardiac lesions in the acute phase of the disease and of cardiac sequelae were higher among infants and old patients.

CONCLUSION

The number of patients with Kawasaki disease and its incidence rate in Japan are continuously increasing.

Searching for the cause of Kawasaki disease--cytoplasmic inclusion bodies provide new insight

Although Kawasaki disease (KD) is the most common cause of acquired heart disease in children in the developed world, its aetiology remains unknown. In this Opinion, Anne Rowley and colleagues discuss evidence, including recently identified cytoplasmic inclusion bodies, which suggests that KD is caused by an infectious agent.

Kawasaki disease (KD) has emerged as the most common cause of acquired heart disease in children in the developed world. The cause of KD remains unknown, although an as-yet unidentified infectious agent might be responsible. By determining the causative agent, we can improve diagnosis, therapy and prevention of KD. Recently, identification of an antigen-driven IgA response that was directed at cytoplasmic inclusion bodies in KD tissues has provided new insights that could unlock the mysteries of KD.

Topological determinants and consequences of adventitial responses to arterial wall injury

Arteries are composed of 3 concentric tissue layers which exhibit different structures and properties. Because arterial injury is generally initiated at the interface with circulating blood, most studies performed to unravel the mechanisms involved in injury-induced arterial responses have focused on the innermost layer (intima) rather than on the outermost adventitial layer. In the present review, we focus on the involvement of the adventitia in response to various types of arterial injury leading to vascular remodeling. Physiologically, soluble vascular mediators are centrifugally conveyed by mass transport toward the adventitia. Moreover, in pathological conditions, neomediators and antigens can be generated within the arterial wall, whose outward conveyance triggers different patterns of local adventitial response. Adventitial angiogenesis, immunoinflammation, and fibrosis sequentially interact and their net balance defines the participation of the adventitial response in arterial pathology. In the present review we discuss 4 pathological entities in which the adventitial response to arterial wall injury participates in arterial wall remodeling. Hence, the adventitial adaptive immune response predominates in chronic rejection. Inflammatory phagocytic cell recruitment and initiation of a shift from innate to adaptive immunity characterize the adventitial response to products of proteolysis in abdominal aortic aneurysm. Adventitial sprouting of neovessels, leading to intraplaque hemorrhages, predominates in atherothrombosis. Adventitial fibrosis characterizes the response to mechanical stress and is responsible for the constrictive remodeling of arterial segments and initiating interstitial fibrosis in perivascular tissues. These adventitial events, therefore, have an impact not only on the vessel wall biology but also on the surrounding tissue.

Epidemiology and etiology of Kawasaki disease

Kawasaki disease was first reported in Japan in 1967 by Dr. Tomisaku Kawasaki. It has since been recognized worldwide, and in at the United States and Japan is the most important cause of acquired heart disease in children, surpassing other more recognized conditions such as rheumatic fever, endocarditis and myocarditis. It is primarily a disease of children less than 5 years of age but has been reported in older children and adults. Risk factors for the illness include Asian ancestry, male gender and certain familial predispositions. Observations such as similarity to certain exanthematous infectious diseases, temporal-geographic clustering of cases and seasonality in incidence favors an infectious etiology. Pathology and pathogenesis of the disease indicate that it is a medium-sized artery vasculitis that results from a dramatic immune activation that in most cases reversed by immune modulating agents such as intravenous immunoglobulin. Unfortunately, the etiology of the illness remains obscure, although recent studies favor a possible viral etiology.