Objective: To assess the clinical and genetic characteristics of symptomatic children with hereditary hemorrhagic telangiectasia (HHT).
Design: Cross-sectional study.
Setting: The HHT clinics in Toronto.
Participants: All children with symptomatic HHT treated from April 1, 1996, through December 31, 2002.
Interventions: Participants were screened for visceral arteriovenous malformations (AVMs). Molecular testing was performed in the children or their affected family members.
Main outcome measures: Prevalence of epistaxis, telangiectases, pulmonary and cerebral AVMs, and genetic characteristics.
Results: Fourteen children presented with manifestations of HHT. Seven had cardiorespiratory symptoms related to pulmonary AVMs. Three had neurological symptoms secondary to bleeding from spinal or cerebral AVMs. Two were referred because of skin telangiectases and 2, because of multiple episodes of epistaxis. Screening results revealed a cerebral AVM in 1 of 11 neurologically asymptomatic children. Of the children without respiratory symptoms, 1 was diagnosed as having definite and 1, suspected pulmonary AVMs. Four children with pulmonary AVMs carried an endoglin gene mutation (HHT type 1), and 1 carried an activin receptor-like kinase 1 gene mutation (HHT type 2). The 2 children with spinal AVMs belong to the same HHT type 2 family. No mutation was found in 1 child with pulmonary and 1 with cerebral AVMs.
Conclusions: Visceral AVMs and mucosal telangiectases are present in children with HHT and can lead to life-threatening events. Failure to identify a disease-associated mutation for each child suggests complex mutations or novel HHT genes.