A Case of Retinal Pigmentary Degeneration in PKAN

ABSTRACT

PURPOSE: Pantothenate kinase-associated neurodegeneration (PKAN), also known as neurodegeneration with brain iron accumulation is an extremely rare degenerative disease. The present study reports a case of retinal pigmentary changes in PKAN. CASE SUMMARY: A 6-year-old girl presented with night blindness and developmental delay. Neurologic examination revealed toe gait and dystonia. Ocular examination showed retinal pigmentary change in the entire retina without optic atrophy. Brain magnetic resonance imaging showed iron deposits in the basal ganglia, the so-called "eye of the tiger" sign. Genetic tests confirmed a mutation in the gene encoding pantothenate kinase 2. Electroretinography demonstrated severe loss of rod and cone responses, prominently reduced in the rod response. The patient was diagnosed with PKAN and pharmacologic treatment started. CONCLUSIONS: In the case of systemic neurological abnormalities with pigmentary retinal change, PKAN should be considered as a differential diagnosis.