RESUMEN
PURPOSE: To report variations in the inheritance pattern and clinical presentation of crystalline retinopathies. METHODS: Two different families with crystalline retinopathy were studied with a complete family history and ophthalmologic examination including Goldmann kinetic perimetry and electroretinography. Genetic studies were performed in one of the families. RESULTS: One of the families had a clearly autosomal dominant mode of inheritance while the other family most likely follows an autosomal recessive pattern. Several members in each family had significant retinal pigment epithelial atrophy, intraretinal crystals, relatively pink optic nerves, and paracentral visual field defects, all of which are clinical features resembling those of Bietti crystalline retinopathy. Examination of peripheral leukocytes using transmission electron microscopy in selected affected members showed no evidence of classical lysosomal crystals that are characteristics for Bietti crystalline retinopathy. No pathogenic mutations were identified in the CYP4V2 gene. CONCLUSIONS: Not all crystalline retinopathies are Bietti's. Further genetic, biochemical, and pathologic studies are required to better differentiate between these retinopathies.