Intravenous Immunoglobulin in Kawasaki Disease-Evolution and Pathogenic Mechanisms

Treatment intensification in Kawasaki disease - current perspectives

INTRODUCTION

Intravenous immunoglobulin is the standard of care in Kawasaki disease. However, a subset of patients exhibits resistance to intravenous immunoglobulin treatment, even when Kawasaki disease is promptly diagnosed and managed. While intravenous immunoglobulin reduces the occurrence of coronary artery abnormalities from 15-25% to 3-5%, it does not entirely eliminate the risk. Besides, management guidelines for non-coronary complications of Kawasaki disease, for instance, myocarditis, remain speculative.

AREAS COVERED

Recent literature suggests that a subset of patients with Kawasaki disease may benefit from treatment intensification with drugs, such as corticosteroids, infliximab, anakinra, and/or ciclosporin. In this manuscript, we have reviewed recent advances in the management of Kawasaki disease, especially with regard to preemptive intensification of therapy in children at high risk of cardiac complications. A comprehensive search was made using Web of Science, Scopus, and PubMed databases to gather English articles published from 1967 to 2023 on the treatment of Kawasaki disease. We incorporated the following words in the search strategy: 'Kawasaki disease,' 'intravenous immunoglobulin/IVIg,' 'intravenous immunoglobulin/IVIg-resistant Kawasaki disease,' 'treatment intensification,' or 'primary intensification of treatment/therapy.'

EXPERT OPINION

The 'high-risk' group in Kawasaki disease needs to be identified with early intensification of primary therapy for better coronary and myocardial outcomes.

Platelets in Kawasaki disease: mediators of vascular inflammation

Kawasaki disease, a systemic vasculitis that affects young children and can result in coronary artery aneurysms, is the leading cause of acquired heart disease among children. A hallmark of Kawasaki disease is increased blood platelet counts and platelet activation, which is associated with an increased risk of developing resistance to intravenous immunoglobulin and coronary artery aneurysms. Platelets and their releasate, including granules, microparticles, microRNAs and transcription factors, can influence innate immunity, enhance inflammation and contribute to vascular remodelling. Growing evidence indicates that platelets also interact with immune and non-immune cells to regulate inflammation. Platelets boost NLRP3 inflammasome activation and IL-1β production by human immune cells by releasing soluble mediators. Activated platelets form aggregates with leukocytes, such as monocytes and neutrophils, enhancing numerous functions of these cells and promoting thrombosis and inflammation. Leukocyte-platelet aggregates are increased in children with Kawasaki disease during the acute phase of the disease and can be used as biomarkers for disease severity. Here we review the role of platelets in Kawasaki disease and discuss progress in understanding the immune-effector role of platelets in amplifying inflammation related to Kawasaki disease vasculitis and therapeutic strategies targeting platelets or platelet-derived molecules.

Emerging evidence of microbial infection in causing systematic immune vasculitis in Kawasaki disease

Kawasaki disease (KD) is a systematic vasculitis that is often complicated by coronary artery lesions and is a leading cause of acquired heart disease in developed countries. Previous studies have suggested that genetic susceptibility, together with an inducing infectious agent, could be involved in KD pathogenesis; however, the precise causative agent of this disease remains unknown. Moreover, there are still debates concerning whether KD is an infectious disease or an autoimmune disease, although many studies have begun to show that various pathogens functioning as critical inducers could activate different kinds of immune cells, consequently leading to the dysfunction of endothelial cells and systematic vasculitis. Here in this review, we attempt to summarize all the available evidence concerning pathogen infections associated with KD pathogenesis. We also discuss the related mechanisms, present a future perspective, and identify the open questions that remain to be investigated, thereby providing a comprehensive description of pathogen infections and their correlations with the host immune system in leading to KD.

[Evidence-based guidelines for the diagnosis and treatment of Kawasaki disease in children in China (2023)]

Kawasaki disease (KD) is an acute self-limiting vasculitis, and it is the most common cause of acquired heart disease in children under 5 years old. One of the improvement goals in pediatric quality control work for the year 2023, as announced by the National Health Commission, is to reduce the incidence of cardiac events and KD-related mortality in children with KD. In order to standardize the diagnosis, treatment, and long-term management practices of KD in China, and effectively prevent and reduce the incidence of coronary artery lesions and long-term adverse effects, the guideline working group followed the principles and methods outlined by the World Health Organization and referenced existing evidence and experiences to develop the "Evidence-based guidelines for the diagnosis and treatment of Kawasaki disease in children in China (2023)". The guidelines address the clinical questions regarding the classification and definition of KD, diagnosis of different types of KD, treatment during the acute phase of KD, application of echocardiography in identifying complications of KD, and management of KD combined with macrophage activation syndrome. Based on the best evidence and expert consensus, 20 recommendations were formulated, aiming to provide guidance and decision-making basis for healthcare professionals in the diagnosis and treatment of KD in children.