Background: Autosomal recessive bestrophinopathy is caused by a mutation in BEST1, which is also associated with autosomal dominant Best disease.
It is a type of retinal dystrophy that presents with characteristic clinical findings. Although studies investigating autosomal recessive bestrophinopathy and conducted outside Japan have indicated that in addition to ocular fundus abnormalities, this disease is often complicated by angle closure, no such studies have been reported in Japan. Here we present a case of autosomal recessive bestrophinopathy in a young patient who also developed bilateral angle closure.
Case: The patient was a 16-year-old girl who had been found to have decreased visual acuity upon admission to primary school, and she had been diagnosed with congenital retinoschisis and a narrow angle in both eyes. Given that an increased intraocular pressure was observed in both the eyes from the age of 16 years, the patient was referred to Tohoku University Hospital for detailed evaluation and treatment. Ophthalmological testing revealed decreased corrected visual acuity (right: 0.8, left: 0.4) accompanied by mild hyperopic astigmatism in both the eyes. The examination also revealed bilateral shallow anterior chambers and extensive peripheral anterior synechiae. Localized serous retinal detachment with macular edema was also detected in the ocular fundus of both the eyes. Although no abnormal findings were noted on intraocular pressure testing or static visual field measurement, electrooculography revealed a unilateral decrease in Arden ratio and genetic analysis identified a homozygous c.C763T (p.R255W) mutation in BEST1, thereby confirming the diagnosis of autosomal recessive bestrophinopathy.
Conclusion: Angle closure may also be observed in Japanese patients with autosomal recessive bestrophinopathy.
Nippon Ganka Gakkai Zasshi (J Jpn Ophthalmol Soc) 124: 720-725, 2020.