Seven cases of hereditary haemorrhagic telangiectasia-like hepatic vascular abnormalities associated withEPHB4pathogenic variants

EPHB4 loss of function is associated with type 2 capillary malformation-arteriovenous malformation syndrome, an autosomal dominant vascular disorder. The phenotype partially overlaps with hereditary haemorrhagic telangiectasia (HHT) due to epistaxis, telangiectases and cerebral arteriovenous malformations, but a similar liver involvement has never been described. Members of the French HHT network reported their cases of EPHB4 mutation identified after an initial suspicion of HHT. Clinical, radiological and genetic characteristics were analysed. Among 21 patients with EPHB4, 15 had a liver imaging, including 7 with HHT-like abnormalities (2 female patients and 5 male patients, ages 43-69 years). Atypical epistaxis and telangiectases were noted in two cases each. They were significantly older than the eight patients with normal imaging (median: 51 vs 20 years, p<0.0006).The main hepatic artery was dilated in all the cases (diameter: 8-11 mm). Six patients had hepatic telangiectases. All kind of shunts were described (arteriosystemic: five patients, arterioportal: two patients, portosystemic: three patients). The overall liver appearance was considered as typical of HHT in six cases.Six EPHB4 variants were classified as pathogenic and one as likely pathogenic, with no specific hot spot. EPHB4 loss-of-function variants can be associated with HHT-like hepatic abnormalities and should be tested for atypical HHT presentations.