Kawasaki-like disease among Italian children in the COVID-19 era.

Verdoni L, Mazza A, Gervasoni A, Martelli L, Ruggeri M, Ciuffreda M, et al. An Outbreak of Severe Kawasaki-like Disease at the Italian Epicentre of the SARS-CoV-2 Epidemic: An Observational Cohort Study. Lancet 2020;395:1771-8.

Question

Among children with Kawasaki-like disease, what is the demographic and disease-related parameters in the COVID-19 era, compared with children diagnosed with Kawasaki disease in the pre-COVID-19 era?

Design

Retrospective, cohort study.

Setting

Bergamo, Italy.

Participants

Children with Kawasaki disease, diagnosed between January 1, 2015, and April 20, 2020.

Intervention

With and without COVID-19 infection.

Outcomes

Incidence. Kawasaki disease shock syndrome was defined by presence of circulatory dysfunction, and macrophage activation syndrome (MAS).

Main Results

The 19 pre-COVID-19 era patients, mean age 3.0 (SD 2.5) years, January 1, 2015 – February 17, 2020, were compared with 10 COVID-19 era patients (80% antibody positive), mean age 7.5 (SD 3.5) years, February 19 – April 20, 2020. Those diagnosed in the COVID-19 era demonstrated a higher incidence: 10 vs 0.3 per month, mean age: 7.5 vs 3.0 years, Kawasaki disease shock syndrome: 50% vs 0%, MAS: 50% vs 0%, and steroid requirement: 80% vs 15%, all P < .01.

Conclusions

Children with Kawasaki disease in the COVID-19 era, 80% of whom were antibody positive, were older and demonstrated more severe disease compared with those with Kawasaki disease prior to the COVID-19 era.

Commentary

A thirty-fold increased incidence of so-called Kawasaki-like disease was reported from Italy during the SARS-CoV-2 epidemic in 2020. Eight of the 10 patients with Kawasaki disease tested positive for COVID-19 with a high incidence (6/10) of cardiac involvement. News from New York, France, and England also showed an increased incidence and severity of Kawasaki disease. Prior to COVID-19, coronavirus had been previously isolated in 7.1% of patients with Kawasaki disease. The incidence of Kawasaki disease is not increasing in Japan, Taiwan, Korea, Hong-Kong, or China, suggesting the importance of genetic issues in the relationship between Kawasaki disease and COVID-19. In this study, the Kobayashi score, which identifies patients at high risk of IVIG resistance, revealed that of the 10 patients with Kawasaki disease, none were younger than 12 months and all had platelet counts less than 300 × 10⁹/L. Results from this study suggest that COVID-19 may be one of the triggers of Kawasaki disease. Kawasaki disease in older patients with COVID-19 is associated with an increased incidence of cardiac involvement, lower platelet counts, MAS, and Kawasaki disease shock syndrome. Early adjunctive steroid treatment to prevent coronary artery lesions should be considered in these patients with COVID-19 Kawasaki disease.