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

Background and Aims: 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 and its deletion results in aortic valve calcification. However, there have been no reports of a patient with CALJA with aortic stenosis. Methods: We describe two extremely rare cases of two sisters with identical NT5E gene mutation patterns, both of whom presented severe aortic stenosis and limb ischemia. Genetic examination for definitive diagnosis was also performed in both patients. Results: Both patients underwent aortic valve replacement and bilateral distal arterial bypass surgeries successfully. They were genetically diagnosed with CALJA based on the NT5E mutation. Conclusions: NT5E mutation should be considered in patients requiring aortic valve replacement for a calcified aortic valve and bypass surgery for specific calcified and occluded arteries.