NT5E mutation in sisters who underwent aortic valve replacements for aortic stenosis

Abstract Mutations of the NT5E gene encoding the cluster of differentiation 73 (CD73) protein have been found in patients with characteristic calcification of joints and arteries (CALJA). CD73 plays a protective role against aortic valve calcification; therefore, its deletion results in aortic valve calcification. However, to date, there are no reports of a patient with CALJA with aortic stenosis. In this study, we describe 2 extremely rare cases of sisters with identical NT5E gene mutation patterns, both of whom developed late-onset severe aortic stenosis and limb ischaemia. Both patients underwent aortic valve replacement and bilateral distal arterial bypass surgeries successfully. They were genetically diagnosed with CALJA based on the NT5E mutation. Our report suggests that NT5E mutations should be considered in patients requiring aortic valve replacement for a calcified aortic valve and bypass surgery for specific calcified and occluded arteries. In 2011, mutation of the NT5E gene that encodes a cluster of differentiation 73 (CD73) was found to result in specific calcifications in patients with aneurysmal dilatation of arteries as well as joint calcifications.