An update on understanding the pathophysiology in Kawasaki disease: Possible role of immune complexes in coronary artery lesion revisited

Kawasaki disease (KD) is an acute self-limiting systemic vasculitis of unknown etiology affecting predominantly the coronary arteries. The role of circulating immune complexes (ICs) in the pathogenesis of KD has been studied using the sera of patients with KD. It has been proposed that ICs are triggered by single or multiple unknown causative agents as well as vasculitis. The outbreak of severe acute respiratory syndrome coronavirus 2 infections caused similar pathophysiology in producing vasculitis, and the RNA virus may have triggered signs and symptoms similar to KD. For clinicians and researchers alike, detecting the causative agents of KD remains a challenge. According to studies in animal models, type III hypersensitivity reactions caused by serum sickness are a prototype for IC vasculitis. The signs and symptoms of coronary artery dilation in swine are similar to those of KD. These models may be used to evaluate new pharmacological agents for KD. The pathogenesis of KD is complex and remains inadequately understood at present. However, circulating ICs may play a key role in the pathophysiology of KD and coronary artery vasculitis. Various therapeutic agents are being explored in the management of KD and these agents act at various stages of the production of pro-inflammatory cytokines and chemokines. In this review, we discuss recent developments in the pathogenesis of KD and provide insights into the innate immune response and mechanisms behind coronary artery damage in KD. We specifically explore the potential role of ICs in the pathogenesis of KD.