ESSENTIALS OF DIAGNOSIS
Fever, conjunctivitis, oral mucosal changes, rash, cervical lymphadenopathy, peripheral extremity changes.
Elevated ESR and CRP levels.
Risk for coronary arteritis and aneurysms.
Kawasaki disease is a worldwide multisystem disease. It is also known as the “mucocutaneous lymph node syndrome.” It occurs mainly in children between the ages of 3 months and 5 years but can occur occasionally in adults as well. Kawasaki disease occurs most often in Asians or native Pacific Islanders. Its incidence in Japan is twice that of the United States, and it occurs among siblings at twice the incidence of cases and at higher rates among parents of cases. These findings plus the known seasonality (higher incidence in winter and early spring) and occasional epidemic pattern of cases point to the inadequate current understanding of the etiology of this disease.
Kawasaki disease is an acute, self-limiting, mucocutaneous vasculitis characterized by the infiltration of vessel walls with mononuclear cells and later by IgA secreting plasma cells that can result in the destruction of the tunica media and aneurysm formation. The cause remains unknown. Epidemiologic studies show an increased risk with advanced maternal age, mother of foreign birth, maternal group B Streptococcus colonization, and early infancy hospitalization for a bacterial illness. Genetic factors are considered to play an important role in the pathogenesis of the disease. Ongoing analyses identify many gene polymorphisms, which significantly correlate with Kawasaki disease susceptibility (at least 23 to disease, and 10 to the presence of coronary aneurysms).
Reports from Bergano, Italy, the epicenter of the 2020 SARS-CoV-2 pandemic in Italy, describe a small cluster of 10 children with a Kawasaki-like disease, called multisystem inflammatory syndrome in children (MIS-C). Those reports come from the peak time of the SARS-CoV-2 pandemic in Bergano (mid-February 2020 to mid-April 2020). Two of 10 children’s nasal swabs tested positive for SARS-CoV-2 PCR and 80% had positive SARS-CoV-2 serology tests, albeit not contemporaneously with the clinical Kawasaki-like disease. Another small cluster of children with MIS-C was reported from England; the first 10 children in the English report tested positive for a SARS-CoV-2 antibody. Since these initial reports, there have been multiple reports of similar disease from the United States and other European countries. This new syndrome raises the question of whether MIS-C is an immune response to SARS-CoV-2.
A clinical diagnosis of classic or “complete” Kawasaki disease requires the presence of at least 5 days of fever, usually high-grade (over 39°C to 40°C) and four of the following five criteria: (1) bilateral nonexudative conjunctivitis (begins shortly after the onset of fever), (2) oral changes of erythema and cracking of lips, strawberry tongue, and erythema of oral and pharyngeal mucosa; (ulcers and pharyngeal exudates are not consistent with Kawasaki disease), (3) peripheral extremity changes (erythema and edema of the hands and feet in the ...