Background: Progressive retinal outer necrosis is a devastating viral necrotizing retinitis, which affects predominantly immunocompromised patients. We report a case in which the ocular findings led to a search for an underlying immune deficiency, established as congenital purine nucleoside phosphorylase deficiency.
Methods: Retrospective, interventional case report.
Results: We describe the clinical features and management of the disease.
Conclusion: This is the first report of bilateral varicella zoster virus retinitis with underlying purine nucleoside phosphorylase deficiency. It highlights the importance of thorough investigation in apparent immunocompetent patients presenting with viral retinitis, as this may indicate an undiagnosed primary immunodeficiency.