P 7Biettis crystalline dystrophy A case-report with pathophysiological description
W. Göbel, H. Siebenbürger, J. Müller
In 1937 Bietti described a chorioretinal and corneal dystrophy with crystalline spots at the posterior pole of the fundus. Crystalline inclusions in the retina and cornea are the most characteristic features of the disease. A progressive degeneration of pigment epithelium and choriocapillaris is present. In 1989 crystalline bodies in lymphocytes of patients with Biettis crystalline dystrophy were reported.
Case-report: A 33-year-old patient presented with decreased night vision. Visual acuity was 20/20 in his right eye and 20/25 in his left eye. Small crystalline bodies were visible throughout the macula and the posterior retina. Small crystals could also be found at the upper corneal limbus. The macula showed irregular areas of chorioretinal atrophy. Fluorescein angiography confirmed window defects of the retinal pigment epithelium and choriocapillaris. In the EOG the Arden-ratio was reduced, whereas the scotopic ERG was normal. Electron-microscopic examination of blood lymphocytes revealed crystalline inclusions in the cytoplasm next to lipofuscin-containing structures.
Conclusion: Compared with literature our patient exhibits all characteristics of Biettis crystalline dystrophy. The histopathologic features of blood lymphocytes seem to be characteristic for the disease and facilitate the diagnosis.
Universitäts-Augenklinik Würzburg, Josef-Schneider-Str. 11, D-97080 Würzburg