Purpose: We present the first detailed ophthalmic description of a child with Helsmoortel-Van der Aa Syndrome (HVDAS), including longitudinal follow-up and analysis.
Observations: After extensive workup, a young child with poor visual behavior, hypotonic cerebral palsy, intellectual disability, and global developmental delay was found to have a heterozygous de novo mutation in the ADNP gene and diagnosed with HVDAS. Ophthalmic findings were remarkable for progressive nystagmus, macular pigment mottling, mild foveal hypoplasia with abnormal macular laminations, persistent rod dysfunction with electronegative waveform, and progressive cone degeneration.
Conclusions and importance: Patients with HVDAS are known to have abnormal visual behavior due to refractive or cortical impairment. However, we present the first description, to our knowledge, of an association with retinal mal-development and degeneration. Thus, patients with HVDAS should be referred for ophthalmic genetics evaluation, and HVDAS should be on the differential diagnosis for young children with global developmental delay who present with nystagmus, rod and cone dysfunction with electronegative waveform, and relative lack of severe structural degeneration on optical coherence tomography.
Keywords: ADNP; Activity-dependent neuroprotective protein; Electronegative waveform; HVDAS; Helsmoortel-Van der Aa Syndrome; Nystagmus; Optical coherence tomography; Retinal degeneration.