Optic nerve atrophy in propionic acidemia

Objective Propionic acidemia is a rare metabolic disorder that is diagnosed in the early neonatal period. The disorder is characterized by life-threatening ketoacidosis, lethargy, failure to thrive, and developmental delay. Herein we report the ocular findings in a prospective series of six patients with propionic acidemia. Design Prospective case series. Participants Six children (three male and three female) between the ages of 2 and 10 years with propionic acidemia who were examined at Children's Hospital Los Angeles. Methods A complete ophthalmic examination was performed on each of the six children. The examination included visual acuity testing, ocular motility, anterior segment examination, and funduscopic evaluation. Emphasis was placed on the function of the optic nerve and on the appearance of the optic disc, looking for possible atrophic changes. Main outcome measures The clinical appearance of the optic disc and evidence of optic neuropathy. Results Optic nerve atrophy was present exclusively in all of the male patients in the series; none of the female patients demonstrated any detectable impairment of optic nerve function. The optic nerve atrophy was symmetric and age dependent and varied from moderate to severe. There were no other anterior or posterior segment abnormalities, other than one case of unilateral morning glory syndrome, diagnosed at birth. There was no correlation between metabolic control and the development and progression of optic nerve atrophy. Conclusions Males with propionic acidemia have moderate to severe bilateral optic atrophy.