Background: Although an etiology of Kawasaki disease (KD) is unknown, an aberrant innate immune system in predisposed individuals has been proposed to play a key role in the development of KD vasculitis. Various etiological pathogens have been proposed as the trigger of KD and a scaled injury preceding symptom onset has been reported as one of them. Here, we report a 17-month-old Japanese female who was hospitalized due to high fever lasting for 4 days with infection ruled out as a cause. On admission, she displayed severe sunburn all over her body following a prolonged period of outdoor play 5 days ago. On the 5 day of illness, she developed complete KD. Serum levels of high mobility group box 1, a representative for damage-associated molecular patterns (DAMPs), were elevated during acute phase and continued to decrease during subacute phase. This unique course suggested the inflammatory process of KD involving innate immunity via DAMPs.

To establish the optimal inflammation control of Kawasaki disease (KD), we investigated the clinical and pathophysiological basis of pericardial effusion (PE) during the acute phase of KD. Clinical and laboratory features of Japanese KD children with PE (PE group: n = 9) and without PE (non-PE group: n = 89) were studied retrospectively by using the medical records. Serum levels of soluble tumour necrosis factor receptor 1 (sTNFR1), interleukin 6 (IL-6), and vascular endothelial growth factor (VEGF) were assessed by enzyme-linked immunosorbent assays (ELISAs). PE group patients had coronary artery lesions (CALs) more frequently than non-PE group patients during the acute phase of KD (33% vs. 5.6%, p = 0.024). PE patients also showed lower levels of haemoglobin (p < 0.01) and serum albumin (p < 0.01) and higher platelet counts (p = 0.013) than non-PE patients. The proportion of neurological symptoms, but not other manifestations, in the PE group was higher than in the non-PE group (p = 0.022). All patients survived free from coronary artery aneurisms. Serum levels of sTNFR1, but not the other cytokines, in the PE group were higher than those in the non-PE group (p < 0.001). The sTNFR1 levels correlated positively with C-reactive protein (CRP) (r = 0.30, p = 0.019) or total bilirubin (r = 0.40, p < 0.01) levels. Acute PE in KD patients indicated the severity of TNF-mediated vascular inflammation and concurrent CALs. According to the progression, these patients might need more targeted therapy of anti-inflammation for a better coronary outcome.

We present a 16-year-old male patient with hypoplastic left heart syndrome who developed protein-losing enteropathy (PLE) and plastic bronchitis (PB) after a Fontan operation. He received medical therapies, including albumin infusion, unfractionated heparin, and high-dose anti-aldosterone therapy but could not obtain clinical relief. Biphasic cuirass ventilation (BCV) led to expectoration of bronchial casts and prompt resolution of PB. Notably, clinical symptoms related to PLE were dramatically improved after starting BCV. A brief period of BCV increased stroke volume from 26±1.4 to 39±4.0 mL. This case suggests that BCV could be an effective treatment for PLE in patients with failing Fontan circulation.