Alport syndrome

Rare familial nephropathy due to abnormalities in type IV collagen.

May be inherited in 1 of 4 patterns: X-linked, autosomal recessive, autosomal dominant or autosomal digenic.

Associated with considerable clinical variability of age of onset of chronic renal failure. Frequently associated with sensorineural hearing loss.

Female carriers of X-linked mutations have a significant lifetime risk of developing hypertension and renal disease.

Strong genotype-phenotype correlations in X-linked Alport syndrome have been described in male patients.

Monitoring and treatment of renal disease is the main treatment.

Alport syndrome is an inherited disease of the glomerular basement membrane caused by abnormalities in type IV collagen.[1]Gubler MC. Inherited diseases of the glomerular basement membrane. Nat Clin Pract Nephrol. 2008 Jan;4(1):24-37. http://www.ncbi.nlm.nih.gov/pubmed/18094725?tool=bestpractice.com It is associated with sensorineural hearing loss, lenticonus (bulging of the lens capsule and the underlying cortex[2]Jacobs K, Meire FM. Lenticonus. Bull Soc Belge Ophtalmol. 2000;(277):65-70. http://www.ncbi.nlm.nih.gov/pubmed/11126676?tool=bestpractice.com ) and retinal abnormalities, as these tissues are additional sites of expression of type IV collagen. The classic thickening and lamellation of the glomerular basement produces a progressive hematuric nephritis that progresses to chronic renal failure in all males with the X-linked form of the disease.[3]Jais JP, Knebelmann B, Giatras I, et al. X-linked Alport syndrome: natural history in 195 families and genotype-phenotype correlations in males. J Am Soc Nephrol. 2000 Apr;11(4):649-57. http://jasn.asnjournals.org/content/11/4/649.full http://www.ncbi.nlm.nih.gov/pubmed/10752524?tool=bestpractice.com