Choroidal neovascularization secondary to angioid streaks in pseudoxanthoma elasticum: case report

Abstract

Objective: pseudoxanthoma elasticum (PXE) is a rare genetic disease, causing fragmentation and calcification of the elastic fibers affecting the skin, cardiovascular system and eyes. Ocular manifestations include angioid streaks, optic nerve drusen, peau d’orange and comet-like peripherical lesions. Angiod streaks (AS) are described as radiating breaks due to dystrophic calcification in the Bruch’s membrane. Common AS related secondary omplication is macular choroidal neovascularization (CNV) which may cause irreversible loss of central vision and blindness. Our purpose is to present a case report of CNV secondary to AS in PXE and to emphasize the importance of differential diagnosis. Methods: the patient was previously treated at a non-tertiary clinic and was referred to a tertiary centre. Full history was obtained and detailed ophthalmic examination with dilated fundoscopy was completed. No anterior segment pathology was found. Best-corrected visual acuity (BCVA) values are represented in decimal. Macular CNV secondary to AS associated with PXE was diagnosed using spectral-domain optical coherence tomography with fundus autofluorescence. Results: A 48-year-old woman was complaining of metamorphopsias in the OD. OS received prior treatment in a non-tertiary clinic with diagnosis of myopic CNV with BCVA 0.02 at present. On clinical examination optic nerve drusen and AS associated with PXE bilaterally were found as well as CNV secondary to AS in the OD. Treatment of IVT bevacizumab injections was started. To this day, 24 IVT injections have been administered with BCVA ranging from 0.02 to 0.5. Conclusions: Since PXE is a rare disorder, the presence of AS should not be overlooked. CNV is a severe secondary complication in the presence of AS associated with PXE. Early detection of CNV and the beginning of a proper treatment may delay disease progression without further implications for visual acuity and help to avoid irreversible vision loss affecting the quality of life. It is necessary to emphasize the importance of differential diagnosis, consultations between ophthalmologists and case reporting, given the rarity of the disorder. The misdiagnosis may lead to the loss of vision and gradually blindness.