Pseudoxantoma elasticum (PXE) is an autosomal recessive disease caused by mutations in the ABCC6 gene. It is characterized by elastic fiber mineralization and fragmentation of connective tissue mostly within the dermis of the skin, Bruch's membrane of the retina, and the mid layers of the arterial blood vessels. Rarely, multiple calcifications have also been reported in PXE patients’ kidneys.
We here report the case of a 40-year-old man who came to our observation for microhematuria, proteinuria, and multiple calcifications in the kidneys detected by ultrasound examination, in the absence of PXE skin lesions. Fundoscopic examination was positive for angioid streaks, and the genetic test confirmed ABCC6 mutation. Fundoscopy can thus be useful for excluding the diagnosis of PXE in patients with isolated multiple calcifications of the kidneys.
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