AD Alport syndrome is characterised by haematuria. Men and women are affected equally often and equally severely. Not everyone with a mutation has haematuria (penetrance is about 67%). Some of those affected develop proteinuria or kidney failure. Their glomerular basement membrane is usually thinned. Hearing loss and ocular abnormalities do not occur.
AR Alport syndrome is characterised by haematuria, proteinuria, progressive kidney failure, hearing loss, land ocular abnormalities (lenticonus, central and peripheral fleck retinopathy). Their glomerular basement membrane is usually lamellated. Often kidney failure onset is at a younger age than in XL disease, and both males and females are also affected equally often and equally severely. AR Alport syndrome may cause kidney failure in a young girl. The hearing loss is first noted in boys in early childhood and progressively worsens until middle age when it plateaus. This mainly affects high-pitched sounds and is helped with the early use of hearing aids. Lenticonus is the conical protrusion of the anterior part of the lens which appears on ophthalmoscopy as an ‘oil droplet’ that moves with movement of the eye. Patients complain of difficulty with focusing. Lenticonus can be corrected with lens replacement, and does not recur. The fleck retinopathy is much more common than lenticonus and may be central or peripheral. It does not affect vision and patients are unaware of it. The flecks surround but do not encroach upon the central retina and may be seen with ophthalmoscopy or non-mydriatic retinal photography. The peripheral retinopathy is more common but may only be evident on non-routine peripheral retinal views. The retinopathy does not require treatment.
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