Acute bilateral visual loss revealing undiagnosed end-stage renal failure: a case report

Acute bilateral visual loss is a neurological and ophthalmic emergency with a broad differential diagnosis. Uremic optic neuropathy (UON) is a rare but potentially reversible cause that may be overlooked, particularly in patients without a prior diagnosis of kidney disease. We report a case in which acute bilateral visual loss, transient focal neurological symptoms, and seizure led to the diagnosis of previously unrecognized end-stage renal failure (ESRF). Visual recovery occurred following initiation of hemodialysis (HD) and correction of associated metabolic abnormalities. A 52-year-old woman with no known medical illness presented with a 3-day history of acute painless bilateral loss of vision. She also reported transient slurred speech that had resolved prior to presentation and persistent bilateral lower-limb weakness. Neuroimaging demonstrated a recent small left insular infarct. Ophthalmic examination revealed visual acuity of counting fingers in both eyes and sluggish pupillary light responses bilaterally, with no apparent relative afferent pupillary defect or optic disc edema. Laboratory investigations revealed markedly elevated serum urea and creatinine levels, severe metabolic acidosis and electrolyte abnormalities, leading to a new diagnosis of ESRF with severe uremia. Following initial HD, visual acuity markedly improved to 6/36 in both eyes. Given the severe uremia at presentation and subsequent visual recovery during correction of the associated metabolic abnormalities, the presentation was considered presumed uremia-associated reversible visual loss, with UON as a possible explanation. This case highlights uremia-associated reversible visual loss as an uncommon but potentially reversible cause of acute bilateral visual loss. Renal dysfunction should be considered in patients presenting with unexplained vision loss, particularly when neuroimaging does not adequately explain the visual presentation and systemic features suggest significant metabolic disturbance. Early recognition and correction of uremia and associated metabolic abnormalities may result in substantial visual recovery.