Differential Clinical Signs of Bietti Corneoretinal Dystrophy (Clinical Case)

Chuprov A. D.
Professor, Doctor of Medicine, Director¹

Pidodniy E. A.
Ophthalmologist¹

1 - Orenburg branch of the S. Fyodorov Eye Microsurgery Federal State Institution of the Ministry of Health of the Russian Federation, Orenburg, Russian Federation

Pidodniy E. A., e-mail: nauka@ofmntk.ru.

The study had no sponsorship.

None declared.

Hereditary retinal dystrophies are clinically and genetically heterogeneous group of conditions, many of which have similar symptoms and functional findings, making correct diagnosis difficult. Bietti corneoretinal dystrophy is a rare form of hereditary retinal dystrophy with an autosomal recessive mode of inheritance. With this dystrophy, yellow-white crystals are visualized on the retina and progressive atrophy of the retinal pigment epithelium, pigment accumulation, and sclerosis of the choriocapillaries are observed. A mutation in the CYP4V2 gene leads to the development of the disease. Currently, 50 different CYP4V2 mutations have been described, most of which are missense mutations. The article presents a clinical case of genetically confirmed Bietti corneoretinal dystrophy with a description of the clinical and functional signs that should be considered when making a diagnosis and taken into account in the differential diagnosis of other hereditary retinal dystrophies. Molecular genetic analysis is necessary in doubtful clinical cases, as well as for genetic counseling of relatives at risk and prenatal testing of high-risk pregnancies.

Bietti corneoretinal dystrophy, genetic analysis, whole exome sequencing, CYP4V2 gene, hereditary retinal dystrophies, missense mutations

10.29234/2308-9113-2022-10-1-60-69

1. Astuti G.D., Sun V., Bauwens M. et al. Novel insights into the molecular pathogenesis of CYP4V2-associated Bietti's retinal dystrophy. Mol Genet Genomic Med. 2015; 3(1): 14-29. doi: 10.1002/mgg3.109.

2. Bagolini B., Ioli-Spada G. Bietti's tapetoretinal degeneration with marginal corneal dystrophy. Am J Ophthalmol. 1968; 65(1): 53-60. doi: 10.1016/0002-9394(68)91028-3.

3. Bietti G. Ueber familiaeres Vorkommen von ‘Retinitis punctata albescens’ (verbunden mit ‘Dystrophia marginalis cristallinea corneae’), Glitzern des Glaskoerpers und anderen degenerativen Augenveraenderungen. Klin Monatsbl Au enheikd 1937; 99: 737-757.

4. Halford S., Liew G., Mackay D.S., Sergouniotis P.I., Holt R. et al. Detailed phenotypic and genotypic characterization of Bietti crystalline dystrophy. Ophthalmology 2014; 121: 1174-84. doi: 10.1016/j.ophtha.2013.11.042.

5. Hu D.N. Genetic aspects of retinitis pigmentosa in China. Am J Med Genet. 1982; 12(1): 51–56. doi: 10.1002/ajmg.1320120107.

6. Hu D.N. Ophthalmic genetics in China. Ophthal Paediat Genet. 1983; 2: 39-45. doi: 10.3109/13816818309007148.

7. Jiao X., Munier F.L., Iwata F., Hayakawa M., Kanai A. et al. Genetic linkage of Bietti crystallin corneoretinal dystrophy to chromosome 4q35. Am J Hum Genet. 2000; 67(5): 1309-1313. doi: 10.1016/S0002-9297(07)62960-7.

8. Kaiser-Kupfer M.I., Chan C.C., Markello T.C., Crawford M.A., Caruso R.C., Csaky K.G., Guo J., Gahl W.A. Clinical biochemical and pathologic correlations in Bietti's crystalline dystrophy. Am J Ophthalmol. 1994; 118(5): 569-582. doi: 10.1016/s0002-9394(14)76572-9.

9. Li A., Jiao X., Munier F.L., Schorderet D.F., Yao W. Bietti crystalline corneoretinal dystrophy is caused by mutations in the novel gene CYP4V2. Am J Hum Genet. 2004; 74(5): 817–826. doi: 10.1086/383228.

10. Park Y.J., Hwang D.J., Seong M.W., Park S.S., Woo S.J. Bietti Crystalline Retinopathy Confirmed by Mutation of CYP4V2 Gene in a Korean Patient. Korean J Ophthalmol. 2016; 30(1): 81-3. doi: 10.3341/kjo.2016.30.1.81.

11. Vargas M., Mitchell A., Yang P. et al. Bietti Crystalline Dystrophy. GeneReviews [Internet] 2012. Available at: https://www.ncbi.nlm.nih.gov/books/NBK91457/.

12. Wada Y., Itabashi T., Sato H., Kawamura M., Tada A., Tamai M. Screening for mutations in CYP4V2 gene in Japanese patients with Bietti's crystalline corneoretinal dystrophy. Am J Ophthalmol. 2005; 139(5): 894-9. doi: 10.1016/j.ajo.2004.11.065.