A Canadian children's hospital's experience with cystic echinococcosis over 30 years: A case series.

Background: Cystic echinococcosis (CE) or hydatid disease caused by the cestode Echinococcus granulosus sensu lato is an uncommon infection in Canada especially among children. There are limited reports describing the clinical presentation and management in Canadian children.

Methods: The medical records of all children diagnosed with CE at a quaternary paediatric centre in Ontario between January 1988 and August 2021 were retrospectively reviewed. The clinical course, management, and outcomes of each case were summarized.

Results: We report two paediatric cases of cystic echinococcosis (CE) in detail and review four additional cases seen at our institution over 33.5 years. The first case was a previously healthy 12-year-old boy with pulmonary CE resulting in unilateral lung collapse and mediastinal shift, who was presumedly infected while living in the Middle East. The second case was a previously healthy 3-year-old girl with pulmonary CE acquired locally in southern Ontario. Four other cases of CE with hepatic involvement (median age 12.5 years) were identified during the study period. Five out of six patients received both surgical and medical therapy.

Conclusion: CE is a rare but serious disease seen in southern Canada that has historically been associated with travel or migration. Due to changes in urban wildlife landscapes and increased global migration, CE may become more prevalent in Canadian children. We describe the first locally acquired case in rural southern Ontario diagnosed at our centre. Prompt recognition of this infection in children by health care providers is important to prevent morbidity and mortality.