Autosomal Dominant Optic Atrophy Plus Syndrome

Abstract

Background: Dominant optic atrophy (DOA) is the most commonly encountered hereditary optic neuropathy in clinical practice and is the result of a mutation in the OPA1 or OPA3 genes encoding mitochondrial membrane proteins. The resultant mitochondrial dysfunction causes a distinct set of ophthalmic findings and may progress to extra-ocular systems known as OPA plus syndrome. We present a case of late-onset OPA plus syndrome encompassing both typical ophthalmic findings and the rarer extra-ocular findings. Case Report: A 41 year-old Caucasian male presents for a second opinion regarding a previously diagnosed traumatic optic neuropathy. Examination revealed decreased best-corrected acuities, optic nerve pallor, optical coherence tomography thinning of the retinal nerve fiber layers, progressive centrocecal visual field defects and tritanomalous color vision defects. All findings proved to be bilateral and symmetric. As the ophthalmic findings were inconsistent with a traumatic optic neuropathy, genetic testing was pursued resulting in a DOA diagnosis. Specialty consults demonstrated high-frequency hearing loss and mitochondrial myopathy consistent with OPA plus syndrome. Conclusion: While not a common diagnosis, hereditary optic neuropathies are most likely to present initially to primary eye care. The practitioner should be familiar with the ophthalmic findings and the need for specialty consult should a DOA diagnosis be confirmed.