GGCX and pseudoxanthoma elasticum (inherited or acquired): These interesting findings may suggest an even greater role for dysfunctional vitamin K metabolism in the pathogenesis of PXE-like syndrome compared to PXE, which can be easily assumed as the decreased VKDP activity in PXE-like syndrome being caused by the direct effect of an abnormally functioning GGCX enzyme due to loss-of-function mutations.