Ultrawide field imaging to document the progression of gyrate atrophy of the choroid and retina over 5 years.

A family of three siblings affected with gyrate atrophy of the choroid and retina is presented. Ultrawide field fundus imaging was used to monitor the progression of the disease objectively over 5 years.

Metabolic follow-up of a Croatian patient with gyrate atrophy and a new mutation in the OAT gene: a case report.

Gyrate atrophy (GA) of the choroid and retina is a rare autosomal recessive disorder that occurs due to deficiency of the mitochondrial enzyme ornithine aminotransferase (OAT). Hyperornithinemia causes degeneration of the retina with symptoms like myopia, reduced night vision and progressive vision loss. Our patient is a 10-year-old girl with impaired vision and strabismus. As part of the metabolic work-up, plasma amino acid analysis revealed significantly increased concentration of ornithine (1039 µmol/L; reference interval 20 - 155 µmol/L). Molecular genetic analysis revealed homozygous mutation in exon 7 of the OAT gene that has not been reported previously (c.868_870delCTT p.(Leu290del)). This in frame deletion was predicted to be deleterious by in silico software analysis. Our patient was treated with pyridoxine (vitamin B6 in a dose of 2 x 100 mg/day), low-protein diet (0.6 g/kg/day) and L-lysine supplementation which resulted in a significant reduction in plasma ornithine concentrations to 53% of the initial concentration and the ophthalmologic findings showed significant improvement. We conclude that low protein diet and lysine supplementation can lead to long-term reduction in plasma ornithine concentrations and, if started at an early age, notably slow the progression of retinal function loss in patients with GA. The effect of therapy can be reliably monitored by periodical measurement of plasma ornithine concentration. To our knowledge, this is the first report of OAT deficiency in Croatia.

Multimodal imaging of foveoschisis and macular pseudohole associated with gyrate atrophy: a family report.

BACKGROUND: To report the results of multimodal imaging of a biochemically confirmed case of a family with gyrate atrophy (GA) associated with foveoschisis and macular pseudohole. CASE PRESENTATION: Two sisters presented to us with progressive bilateral decreased vision. The 26-year old sister had a best corrected visual acuity (BCVA) of 20/32 in the right eye (RE) and 20/100 in the left eye (LE). Dilated fundus examination revealed multiple bilateral chorioretinal atrophy areas in the midperipheral and peripheral retina. Fluorescein angiography did not show any leak in the macular area. Swept-source optical coherence tomography (SS-OCT) showed increased central macular thickness in both eyes with foveoschisis. Optical coherence tomography angiography (OCTA) showed petaloid non-reflective areas and some perifoveal microvascular alterations similar to telangiectasias in the deep capillary complex. The 30-year-old sister had a BCVA of 20/20 in the RE and 20/32 in the LE. SS-OCT was normal in the RE and demonstrated a macular pseudohole with a fine epiretinal membrane in the LE. The persistent retinal tissue at the base of the pseudohole was disorganised. Blood tests showed hyperornithinemia in the 2 cases. Based on these observations, the patients were diagnosed with gyrate atrophy of the choroid and retina and were treated with a pyridoxine supplement and an arginine-restricted diet. CONCLUSIONS: Foveoschisis and macular pseudohole may be associated in GA, increasing the risk of rapid vision loss. OCTA is an interesting imaging tool that can help to better understand the pathophysiological mechanism of these macular involvements in GA.

Unique case of gyrate atrophy with a well-preserved electroretinogram (ERG).

Gyrate atrophy is a rare autosomal recessive disorder caused by a mutation in the ornithine-δ-amino transferase gene. We present an interesting case of a 33-year-old woman who presented with increasing myopia, nyctalopia and failing vision. Examination revealed posterior subscapsular cataracts, narrowed peripheral visual fields and scalloped atrophic peripheral chorioretinal lesions. Blood investigations showed a raised plasma ornithine level at 917 µmol/L (normal range: 32-88 µmol/L) confirming the diagnosis of gyrate atrophy. The patient, despite not tolerating dietary treatment, had retained central vision over a follow-up period of 18 years. The electroretinogram, which normally diminishes with disease progression, was still nearly normal when last tested at 16 years follow-up. Genetic testing did not reveal any novel mutation that could account for this variation.

[Gyrate atrophy of the choroid and retina in children]. / Zanik girlandowaty naczyniówki i siatkwki u dzieci.

THE AIM: the history and clinical findings of 3.5 and 5.5-years old siblings with gyrate atrophy (GA) of the choroid and retina are presented. PATIENTS AND METHOD: Siblings: a girl at the age 3.5 years and her brother 5.5 years were examined. Clinical and biochemical findings were performed. RESULTS: The best corrected visual acuity of both girl and boy was below normal values. Myopia of middle degree and myopic astigmatism was presented in both eyes of siblings. On fundus examination sharply defined bizarre shaped atrophic areas of peripheral choroid and retina were seen in both eyes of children. Fluorescein angiography of gyrate atrophy. The boy's plasma ornithine level was increased to 974.950 umol/L and the girl's to 1007.188 umol/L. The concentration of ornithine, lysine and arginine in the urea of these patients was high. CONCLUSION: Early clinical and biochemical diagnosis of gyrate atrophy of the choroid and retina in children is very important, because low protein diet with elimination of arginine can reduce the progression of this severe disease.