[A young man with intestinal polyposis and epistaxis]. / Een jongeman met intestinale polyposis en epistaxis.

BACKGROUND: Germline mutations in the SMAD4 gene lead to both juvenile polyposis syndrome and hereditary haemorrhagic telangiectasia (HHT). CASE DESCRIPTION: A 23-year-old man underwent colectomy with ileo-anal pouch anastomosis at the age of 12 due to colorectal juvenile polyposis. At follow-up, recurrent juvenile polyps in the pouch were removed. No gastric polyps were found. The family history was negative for intestinal polyposis. In addition, the patient had recurrent epistaxis. DNA testing revealed a pathogenic SMAD4 mutation: c.1558G>T; p.(Glu520*). Further examination confirmed suspected HHT. CONCLUSION: DNA testing in patients with juvenile polyposis is important for subclassification of this syndrome with implications for the management of patients and family members.