Spatiotemporal clustering of cases of Kawasaki disease and associated coronary artery aneurysms in Canada.

Detailed epidemiologic examination of the distribution of Kawasaki disease (KD) cases could help elucidate the etiology and pathogenesis of this puzzling condition. Location of residence at KD admission was obtained for patients diagnosed in Canada (excluding Quebec) between March 2004 and March 2015. We identified 4,839 patients, 164 of whom (3.4%) developed a coronary artery aneurysm (CAA). A spatiotemporal clustering analysis was performed to determine whether non-random clusters emerged in the distributions of KD and CAA cases. A high-incidence KD cluster occurred in Toronto, ON, between October 2004 and May 2005 (116 cases; relative risk (RR) = 3.43; p < 0.001). A cluster of increased CAA frequency emerged in Mississauga, ON, between April 2004 and September 2005 (17% of KD cases; RR = 4.86). High-incidence clusters also arose in British Columbia (November 2010 to March 2011) and Alberta (January 2010 to November 2012) for KD and CAA, respectively. In an exploratory comparison between the primary KD cluster and reference groups of varying spatial and temporal origin, the main cluster demonstrated higher frequencies of conjunctivitis, oral mucosa changes and treatment with antibiotics, suggesting a possible coincident infectious process. Further spatiotemporal evaluation of KD cases might help understand the probable multifactorial etiology.

Epidemiology of Kawasaki Disease in Canada 2004 to 2014: Comparison of Surveillance Using Administrative Data vs Periodic Medical Record Review.

BACKGROUND: We have previously documented an increase in the incidence of Kawasaki disease (KD) in Ontario followed by a stabilization from 1995 to 2006. We sought to validate the estimation of incidence of KD using administrative data and to describe the epidemiology of KD across Canada from 2004 to 2014. METHODS: We queried the Canadian Hospital Discharge Database for hospital admissions associated with a discharge diagnosis of KD. The data set was manually curated and estimates of incidence were compared with those obtained from the retrospective triennial surveillances of KD performed in 2007 and 2010. RESULTS: The average number of cases per year identified through administrative data was 245 ± 45 vs 229 ± 33 from retrospective surveillance. This overestimation, representing 7 ± 6%, is similar to the historical percentage of patients originally diagnosed with KD in whom the diagnosis is subsequently excluded. The annual incidence of KD in Canada was 19.6, 6.4, and 1.3 cases per 100,000 children younger than 5 years, 5-9 years, and 10-14 years old, respectively, with important regional and seasonal differences. The incidence remained stable over the study period in the youngest age group but increased in both older age categories. Coronary artery aneurysms affected 3.5% of all patients, and 0.8% experienced associated major cardiac complications. CONCLUSIONS: Reliance on administrative data to determine incidence of KD is feasible and accurate with manual curation of the data. The incidence of KD in Canada seems to have plateaued for younger children. Differences in annual incidence observed between provinces remain to be explained, and might reflect genetic or environmental differences.

Environmental epidemiology of Kawasaki disease: Linking disease etiology, pathogenesis and global distribution.

BACKGROUND: The pathogenesis of Kawasaki disease (KD) is commonly ascribed to an exaggerated immunologic response to an unidentified environmental or infectious trigger in susceptible children. A comprehensive framework linking epidemiological data and global distribution of KD has not yet been proposed. METHODS AND FINDINGS: Patients with KD (n = 81) were enrolled within 6 weeks of diagnosis along with control subjects (n = 87). All completed an extensive epidemiological questionnaire. Geographic localization software characterized the subjects' neighborhood. KD incidence was compared to atmospheric biological particles counts and winds patterns. These data were used to create a comprehensive risk framework for KD, which we tested against published data on the global distribution. Compared to controls, patients with KD were more likely to be of Asian ancestry and were more likely to live in an environment with low exposure to environmental allergens. Higher atmospheric counts of biological particles other than fungus/spores were associated with a temporal reduction in incidence of KD. Finally, westerly winds were associated with increased fungal particles in the atmosphere and increased incidence of KD over the Greater Toronto Area. Our proposed framework was able to explain approximately 80% of the variation in the global distribution of KD. The main limitations of the study are that the majority of data used in this study are limited to the Canadian context and our proposed disease framework is theoretical and circumstantial rather than the result of a single simulation. CONCLUSIONS: Our proposed etiologic framework incorporates the 1) proportion of population that are genetically susceptible; 2) modulation of risk, determined by habitual exposure to environmental allergens, seasonal variations of atmospheric biological particles and contact with infectious diseases; and 3) exposure to the putative trigger. Future modelling of individual risk and global distribution will be strengthened by taking into consideration all of these non-traditional elements.

Surgical repair of pulmonary artery sling in an adult.

Pulmonary artery sling is a rare congenital vascular anomaly that typically presents in the first month of life with severe respiratory symptoms. In this condition, the left pulmonary artery originates off the right pulmonary artery and courses between the trachea and esophagus, causing compression of both structures. Of those patients with pulmonary artery sling, a small subset survives to adulthood with few or no symptoms. In this article we present the surgical correction of pulmonary artery sling in an adult patient.