Bothnia Retinal Dystrophy is a rare atypical type of retinitis pigmentosa. Patients usually present in early childhood with night blindness, which progresses to retinitis punctata albescens and macular degeneration by the early teenage years. Affected individuals suffer from progressive loss of visual acuity and are legally blind by early adulthood.
Electrophysiological studies have helped identify the progressive course of this disorder. Patients early in the disease course have a normal fundus appearance, but begin to show a loss of rod function within the first decade. Over time, affected individuals lose cone responses as well. Dark adaptometry tests have found that rod responses recover after prolonged dark adaptation of 20-24 hours but cone responses do not recover.
The condition has a particularly high prevalence in the Vasterbotten County of northern Sweden and is hence also known as Vasterbotten Dystrophy. It can be diagnosed based on ophthalmological studies and molecular diagnosis of the RLBP1 gene. There is currently no cure for the condition. However, patients may benefit from tinted lenses and low-vision aids as well as therapy to help adapt to the progressive vision loss. Prenatal testing and genetic counselling may be useful for family members of affected individuals.