ELN and Pseudoxanthoma elasticum: PXE (also known as Grönblad-Strandberg syndrome, elastosis dystrophica or elastodysplasia calcificans) is a rare inherited disease (OMIM 264800, prevalence 1/25,000 to 1/50,000) characterized by a generalized accumulation of calcified and fragmented elastic fibers selectively affecting the elastin-rich tissues such as the skin, the retina and the vascular wall.