Males with XL Alport syndrome tend to have more severe disease than females. An affected boy may have blood in his urine from the age of 6 and then develop protein in his urine and a hearing loss before the age of 10. He may require a kidney transplant in his twenties. The eye abnormalities are less common, and do not affect vision (fleck retinopathy) or are easily treatable (lenticonus). Affected females tend to have milder disease with haematuria in nearly everyone but sometimes later onset kidney failure (requiring dialysis or a kidney transplant). However hearing loss is common in affected women but the association with Alport syndrome may not be recognised. Overall females are affected twice as often as males with XL Alport syndrome, and although the risk of kidney failure is less, half a women’s sons and half her daughters will inherit the mutation and the disease.
COL4A5