Etiological role of phagocytes in Kawasaki disease

The numbers of immature neutrophils and monocytes in the peripheral blood are increased in the acute phase of Kawasaki disease. These phagocytes contain toxic granules and vacuoles in the cytoplasm. Phagocytes are primed and activated to release active oxygen species, lysosome enzymes and chemical mediators, which injure cultured endothelial cells and vascular smooth muscle cells. One of the possible factors causing cardio-vascular complications in Kawasaki disease is these activated phagocytes. Some microbial agents or their products such as toxins may activate neutrophils and monocytes, but the real cause remains unknown.