Figure 3.

Glomerular basement membrane (GBM) appearance and patterns of hearing loss in women with Alport syndrome. (A) Electron micrograph of kidney biopsy from a 40-year-old woman demonstrating a variably thinned glomerular capillary basement membrane, <200 nm in places, but without multilamellation, splitting, or GBM microparticles. The appearance was indistinguishable from thin membrane nephropathy and was misdiagnosed until recent genetic testing confirmed X-linked Alport syndrome; (B) audiometry 30 years later (age 70) from the same woman with X-linked Alport syndrome due to a R373× mutation in COL4A5 demonstrating a high tone sensorineural hearing loss in the left ear (above 6000 Hz); and (C) audiometry from a 50-year-old with X-linked Alport syndrome demonstrating a midtone sensorineural loss in the right ear.