Kawasaki disease shock syndrome: Case report and cytokine profiling

Acute Appendicitis as the Initial Presentation of Kawasaki Disease Shock Syndrome in Children

Kawasaki disease shock syndrome (KDSS) is a severe form of Kawasaki disease (KD). The hemodynamic instability and atypical manifestations of this syndrome delay its correct diagnosis and timely treatment. We report here an eight-year-old girl who presented with appendicitis. Her fever persisted after appendectomy, accompanied by hemodynamic instability. The girl was diagnosed with KDSS. Intravenous immunoglobulin (IVIG) and corticosteroids were administered. Her symptoms resolved. She had left coronary artery dilatation, which resolved three months later. We also reviewed two other possible cases identified as KDSS with appendicitis. These cases have a more atypical clinical course, prolonged treatment, and a higher rate of IVIG resistance. Better awareness of KDSS is needed for early diagnosis and treatment in children experiencing prolonged fever after appendectomy.

Kawasaki Disease Shock Syndrome in Japan and Comparison With Multisystem Inflammatory Syndrome in Children in European countries

Multisystem inflammatory syndrome in children (MIS-C) is a severe Kawasaki-like illness that was first linked to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in European countries in the spring of 2020 and has been suggested to have overlap with Kawasaki disease shock syndrome (KDSS). There are few reports of MIS-C from Asia. This observational study aimed to identify the clinical features in children presenting with KDSS in Japan over a 5-year period and to summarize similarities and differences between KDSS and MIS-C. We retrospectively collected data on patient characteristics, clinical signs and symptoms, treatment, and prognosis including coronary artery abnormalities (CAAs), which were compared with data of patients with KDSS worldwide and patients with MIS-C from a review. KDSS was identified in 6 (1.1%) of 552 patients with Kawasaki disease (KD) treated at a single institution in Japan between 2015 and 2020 (1 in 2020). In patients with KDSS in Japan or worldwide vs. patients with MIS-C, KDSS was more likely to have a diagnosis of complete KD (100, 70 vs. 6.3%), a higher incidence of CAAs (50, 65 vs. 11%), and a greater requirement for vasoactive agonists (67, 67 vs. 43%) because of circulatory shock (100, 50 vs. 26%). Both KDSS and MIS-C had good prognosis (mortality 0, 6.7 vs. 1.7%). Although KDSS in Japan and MIS-C show some overlap in clinical symptoms, they are unlikely to be the same disease entity. KDSS is more likely to have a cardiovascular phenotype with CAAs and requires treatment with cardiovascular agents.

Perspective of Immunopathogenesis and Immunotherapies for Kawasaki Disease

Kawasaki Disease (KD) is an acute inflammatory illness that mostly occurs in children below 5 years of age, with intractable fever, mucocutaneous lesions, lymphadenopathy, and lesions of the coronary artery (CAL). KD is sharing clinical symptoms with systemic inflammatory syndrome in children (MIS-C) which is related to COVID-19. Certain genes are identified to be associated with KD, but the findings usually differ between countries and races. Human Leukocyte Antigen (HLA) allele types and toll-like receptor (TLR) expression are also correlated to KD. The acute hyperinflammation in KD is mediated by an imbalance between augmented T helper 17 (Th17)/Th1 responses with high levels of interleukin (IL)-6, IL-10, IL-17A, IFN-γ, and IP-10, in contrast to reduced Th2/Treg responses with lower IL-4, IL-5, FoxP3, and TGF-β expression. KD has varying phenotypic variations regarding age, gender, intravenous immunoglobulin (IVIG) resistance, macrophage activation and shock syndrome. The signs of macrophage activation syndrome (MAS) can be interpreted as hyperferritinemia and thrombocytopenia contradictory to thrombocytosis in typical KD; the signs of KD with shock syndrome (KDSS) can be interpreted as overproduction of nitric oxide (NO) and coagulopathy. For over five decades, IVIG and aspirin are the standard treatment for KD. However, some KD patients are refractory to IVIG required additional medications against inflammation. Further studies are proposed to delineate the immunopathogenesis of IVIG-resistance and KDSS, to identify high risk patients with genetic susceptibility, and to develop an ideal treatment regimen, such as by providing idiotypic immunoglobulins to curb cytokine storms, NO overproduction, and the epigenetic induction of Treg function.