Histopathological Characteristics of Post-inflamed Coronary Arteries in Kawasaki Disease-like Vasculitis of Rabbits

Risk factors associated with progression and persistence of small- and medium-sized coronary artery aneurysms in Kawasaki disease: a prospective cohort study

To identify the risk factors of progression and persistence of small- and medium-sized coronary artery aneurysm (CAA) in a contemporary cohort of patients with Kawasaki disease (KD) and to determine the relationship between CAA progression and persistence. A total of 89 KD patients with small- and medium-sized CAA were prospectively enrolled. All patients were followed up at least for 2 years by serial echocardiography. Multivariate logistic regression analysis was conducted to evaluate independent risk factors for CAA progression and persistence. A total of 46 (51.7%) and 73 (82.0%) patients showed echocardiographic CAA regression by 1 month and 24 months of follow-up, respectively. CAA progression was documented in 12 (13.5%) patients during follow-up. The initial aneurysm size according to CAA classification (OR 0.089, 95% CI 0.013-0.634, P = 0.016) and CAA progression (OR 42.618, 95% CI 3.740-485.6, P = 0.003) were independently associated with CAA persistence. The number of involved coronary arteries (OR 0.223, 95% CI 0.065-0.767, P = 0.015) and lymphocyte proportion (OR 1.327, 95% CI 1.019-1.727, P = 0.040) were independently associated with CAA progression.Conclusion: Patients with KD and greater initial aneurysm size, CAA progression, more involved coronary arteries, and lower lymphocyte proportion may require intensive cardiac monitoring and adjuvant therapies.What is Known:• Long-term outcomes of patients with KD and CAA are primarily driven by the consequences of CAA regression and progression.• Regression and progression occurs more frequently in patients with small- and medium-sized CAAs, and less frequently for giant CAAs.What is New:• The CAA size at diagnosis, NCAI, and the proportion of lymphocytes are presumably associated with the small- and medium-sized CAA persistence or CAA progression.• The CAA progression was associated with CAA persistence.

A novel mouse model of coronary stenosis mimicking Kawasaki disease induced by Lactobacillus casei cell wall extract

Kawasaki disease (KD), a febrile systemic vasculitis in infants associated with coronary aneurysm, is a major cause of cardiac sequelae such as myocardial infarction (MI) and sudden death. These events are caused by coronary stenosis due to intimal proliferation or thrombotic formation; however, histological evaluation is limited to autopsy cases of human KD. We therefore investigated the histological features of coronary artery (CA) stenosis in mice induced by Lactobacillus casei cell wall extract (LCWE). LCWE-induced coronary inflammation gradually progressed in a time-dependent manner and expanded to all layers of the vessel wall over 28 days. In addition, frequent elastin degradation was observed and abundant α-smooth muscle actin (SMA)-positive vascular smooth muscle cells (VSMCs) infiltrated into the intima. Furthermore, most VSMCs were positive for proliferating cell nuclear antigen (PCNA) following staining, suggesting that VSMCs likely exhibited a proliferative phenotype. In conclusion, we show a novel mouse model of coronary stenosis induced by LCWE that is characterized by coronary stenosis with severe coronary vasculitis and elastin degradation. In addition, VSMC proliferation plays an important role in the formation of coronary stenosis. This model is an appropriate model of KD coronary stenosis.

Aetiological Significance of Infectious Stimuli in Kawasaki Disease

Kawasaki disease (KD) is a pediatric vasculitis syndrome that is often involves coronary artery lesions (e. g., coronary artery aneurysms). Although its causal factors and entire pathogenesis remain elusive, the available evidence indicates that the pathogenesis of KD is closely associated with dysregulation of immune responses to various viruses or microbes. In this short review, we address several essential aspects of the etiology of KD with respect to the immune response to infectious stimuli: 1) the role of viral infections, 2) the role of bacterial infections and the superantigen hypothesis, 3) involvement of innate immune response including pathogens/microbe-associated molecular patterns and complement pathways, and 4) the influence of genetic background on the response to infectious stimuli. Based on the clinical and experimental evidence, we discuss the possibility that a wide range of microbes and viruses could cause KD through common and distinct immune processes.

Perivascular Adventitial Fibroblast Specialization Accompanies T Cell Retention in the Inflamed Human Dermis

Perivascular accumulation of lymphocytes can be a prominent histopathologic feature of various human inflammatory skin diseases. Select examples include systemic sclerosis, spongiotic dermatitis, and cutaneous lupus. Although a large body of work has described various aspects of the endothelial and vascular smooth muscle layers in these diseases, the outer adventitial compartment is poorly explored. The goal of the current study was to characterize perivascular adventitial fibroblast states in inflammatory human skin diseases and relate these states to perivascular lymphocyte accumulation. In normal skin, adventitial fibroblasts are distinguished by CD90 expression, and dense perivascular lymphocytic infiltrates are uncommon. In systemic sclerosis, this compartment expands, but lymphocyte infiltrates remain sparse. In contrast, perivascular adventitial fibroblast expression of VCAM1 is upregulated in spongiotic dermatitis and lupus and is associated with a dense perivascular T cell infiltrate. VCAM1 expression marks transitioned fibroblasts that show some resemblance to the reticular stromal cells in secondary lymphoid organs. Expanded adventitial compartments with perivascular infiltrates similar to the human settings were not seen in the inflamed murine dermis. This species difference may hinder the dissection of aspects of perivascular adventitial pathology. The altered perivascular adventitial compartment and its associated reticular network form a niche for lymphocytes and appear to be fundamental in the development of an inflammatory pattern.