CLINICAL-FEATURES AND PATHOGENESIS OF ALPORT RETINOPATHY

Background: Alport syndrome refers to the clinical triad of hereditary nephritis, sensorineural deafness, and ocular abnormalities. Ultrastr uctural findings in the lens capsule and in the renal glomeruli have p rovided evidence that abnormal basement membranes are elaborated in af fected tissues of patients with this disorder. Recently, the results o f several linkage studies have allowed the genetic defect in Alport sy ndrome to be mapped to a locus that codes for a subtype of type IV col lagen (alpha 5) known to be present in glomerular basement membranes. In spite of these advances, the nature of the retinal flecks in Alport syndrome and the visual consequences of the flecks remain controversi al. Methods: Detailed psychophysical and electrophysiologic testing wa s performed in a young man with Alport syndrome. The concurrence of an unusually extensive fleck retinopathy and unilateral pseudophakia aff orded a unique opportunity to assess the effect of the flecks on retin al function. Results: No sensory deficits were present in the eye with clear media. Conclusion: Macular flecks in Alport syndrome are not as sociated with demonstrable retinal dysfunction. The authors address qu estions about the nature and pathogenesis of the flecks in light of ne w clinical and genetic information.