Severe visual impairment as a complication of autism spectrum disorder.

PURPOSE: To report the irreversible vision loss caused by optic neuropathy in a course of a vitamin A deficiency. METHODS: Electroretinography (ERG) and pattern visual evoked potentials (PVEP) were used to establish a diagnosis, and to monitor the treatment in a child suffering from poor vision likely as a result of vitamin A deficiency. RESULTS: A 13-year-old boy presented with eye pain, dryness, itching, photophobia, and decreased vision for the past 4 weeks. His medical history was significant for autism spectrum disorder, anxiety-depressive disorder, and eating disorder-neophobia. His visual acuity was severely impaired, measuring 1.2 LogMAR in the right eye and 1.0 LogMAR in the left eye. Slit lamp examination revealed keratinization of the conjunctiva and multiple punctate epithelial defects of the cornea. Optical coherence tomography (OCT) confirmed keratomalacia. The patient was referred to the Pediatric Gastroenterology Unit for further investigation and found to have severe malnutrition including hypovitaminosis A (< 0.05 μmol/L). Treatment included vitamin A supplementation, 200 000 IU, bandage contact lenses, moxifloxacin, and lubricant eye drops. Although it was impossible to perform ERG on the initial visit because of patients' poor general and ocular condition, full field ERGs showed generalized retinal dysfunction after 12 days of treatment. After 11 months, full field ERGs revealed retinal function within normal limits, but the patient's vision remained poor. Pattern visual evoked potentials (PVEPs) suggested persistent optic nerve dysfunction. CONCLUSION: Electrophysiological assessments, including ERG and (PVEP) were central to establishing an accurate diagnosis in cases where resolution of anterior segment lesions due to keratomalacia did not result in visual improvement. These tests are critical for the identification and monitoring of nutritional optic neuropathy.