Summary of 21 symptomatic children with visceral arteriovenous malformations(AVMs)
| Female sex | 10 (48) |
| Positive family history | 17 (81) |
| Positive genetic testing | 12 (57) (5 ALK1; 6 ENG; 1 SMAD4) |
| Positive family genetics# | 4 (19) (3 ALK1; 1 ENG) |
| Telangiectasia | 8 (38) |
| Epistaxis | 14 (67) |
| AVMs | |
| Pulmonary | 9 (43) |
| Cerebral | 5 (24) |
| Pulmonary and cerebral | 2 (10) |
| Spinal | 2 (10) |
| Hepatic | 3 (14) |
| Diagnostic criteria | |
| Four | 4 (19) |
| Three | 10 (48) |
| Two | 7 (33)¶ |
Data are presented as n (%). ALK1: activin receptor-like kinase1 gene; ENG: endoglin gene; SMAD4: SMAD family member 4 gene. #: children untested; ¶: six children had a positive family history of hereditary haemorrhagic telangiectasia and one child had a positive test result for a disease-causing gene mutation.