Diagnosis in a patient with fundus albipunctatus and atypical fundus changes.

We report a case of an 11-year old Caucasian female with nyctalopia since early childhood with an atypical clinical presentation of fundus albipunctatus (FA), and a novel mutation in the RDH5 gene. In addition to white spots in the fundus, patchy areas of hypopigmentation were noted, which were reminiscent for an early stage of retinitis punctata albescens (RPA). Electroretinographic testing (ERG) showed a non-detectable, dark adapted, isolated rod response and a markedly decreased combined rod and cone response to an achromatic stimulus. After patching one eye overnight, both the isolated rod response and combined rod and cone scotopic white flash response were normal. A Goldmann-Weekers dark adapted final threshold response was also within the normal range. The patient showed a previously reported heterozygous mutation for Gly238Trp, and a novel Arg157Gln mutation. Genetic testing and extended ERG and psychophysical testing may be necessary to diagnose FA from early stages of progressive RPA.