Fig. 1: Clinical presentation of ENPP1 deficiency.

(a) Histopathology of the aorta of the first brother of patient 6 (deceased at 49 days), showing pronounced thickening of the tunica intima (indicated by white line, both in affected aorta and in the insert depicting a normal aorta) with consequent luminal narrowing, as well as internal elastic lamina distorted by dystrophic calcification (black arrows). (b) Histopathology of the heart of the second brother of patient 6 (deceased at 38 days), revealing deposition of calcium along the internal elastic lamina (disparate elastic fibers with severe degenerative changes separating the media from the intima), accompanied by fibrous thickening of the intima that results in luminal narrowing of the right coronary artery (hematoxylin and eosin [H&E]). (c) Coronal computed tomography (CT) of patient 6 at 4 weeks of life, showing calcification of the distal abdominal aorta and proximal bilateral iliac arteries (yellow arrows). (d) Axial CT scan of patient 6 at 4 weeks of life showing calcification (yellow arrows) of the left main (LM), left anterior descending (LAD) and left circumflex (LCX) coronary arteries. (e) Three-dimensional CT reconstruction of patient 10 at 5 years old revealing bilateral external iliac artery occlusion (yellow arrows) with prominent collaterals.