Some patients with Juvenile Polyposis Syndrome (JPS) will also have Hereditary Hemorrhagic Telangiectasia (HHT).

Affected gene: SMAD4 (at 18q21.2)


Typically there is a family history with an autosomal dominant pattern of inheritance.


Clinical features of juvenile polyposis syndrome:

(1) upper GI polyps, especially stomach

(2) increased risk of gastric cancer

(3) presence of juvenile polyps elsewhere in the GI tract


Clinical features of hereditary hemorrhagic telangiectasia syndrome:

(1) epistaxis

(2) telangiectasia

(3) arteriovenous malformations (AVM), especially pulmonary

(4) digital clubbing

(5) anemia


Additional findings:

(1) exercise intolerance

(2) migraine headaches

To read more or access our algorithms and calculators, please log in or register.