Gazing Into the Crystal Ball: Calciphylaxis Causing Striking Retinal Vascular Calcification, Ocular Ischemic Syndrome, Crystalline Retinopathy, and Ischemic Optic Neuropathy.

ABSTRACT A 72-year-old woman with membranous glomerulonephritis and failed renal transplant on peritoneal dialysis presented with bilateral vision loss. She reported several months of diminishing right eye vision that worsened after cataract extraction. On presentation, visual acuity was hand motion in the right and 20/100 in the left eye with a right afferent pupillary defect. Confrontation visual fields were constricted bilaterally. Intraocular pressure was 23 in the right eye, and there was diffuse right eye central corneal opacity with iris neovascularization. Fundus examination revealed bilateral pale optic nerves with cotton wool spot inferior to the left optic disc and diffuse arteriolar whitening with crystalline deposits in the left macula. Given fundus appearance, concurrent ischemic optic neuropathy, and ocular ischemic syndrome, ocular calciphylaxis was suspected. The patient reported development of painful gluteal nodules a month prior, and biopsy revealed calcinosis cutis, a dermatopathologic finding on the spectrum of calcific vasculitides. Her vision continued to decline in both eyes with left eye vision of 20/400. Intravenous sodium thiosulfate through hemodialysis was started with initial improvement in left eye vision to 20/125, but subsequently declined despite treatment. Pathogenesis of systemic calciphylaxis is poorly understood but believed to result from upregulation of osteogenesis and decreased inhibition of vascular calcification in parathyroid axis dyscrasias due to end-stage renal disease. Excess serum calcium-phosphate deposits in blood vessels causing tissue infarction, most commonly in the skin. Prior case reports have described ischemic optic neuropathy mimicking giant cell arteritis and crystalline retinopathy with ocular ischemic syndrome separately. Treatment with empiric intravenous sodium thiosulfate and calcium chelation may preserve vision in some patients.