Family Phenotypic Profile in Hereditary Hemorrhagic Telangiectasia: Genotype-Phenotype Correlation in the Pediatric Population

Hereditary Hemorrhagic Telangiectasia (HHT) is a rare, hereditary, autosomal dominant vascular disease, characterized by arteriovenous malformations (AVM), mucocutaneous telangiectasias and epistaxis. The management of pediatric patients is currently based on limited literature. The aim of our study is to evaluate whether the severity of HHT in affected children could be compared to their parents ‘phenotype, sharing the same genetic variants. We collected data about 11 pediatric patients and their parents with a confirmed diagnosis of HHT, from the medical records of Fondazione Policlinico Universitario A. Gemelli IRCCS (Rome, Italy). Starting from the analysis of the genotype-phenotype correlations among pediatric patients and their affected parents, we found that in three families (33,3%) the HHT presentation was similar between affected adults and affected siblings. In six families (67,7%) HHT phenotype was different between parents and children, being frequently more severe in parents rather than in children. Our results revealed a series of evidence confirming that HHT has variable phenotypic expressiveness.