Genetic Hearing Loss Associated with Renal Disorders

Question 1

What is Alport syndrome?

Answer 1

Nephritis and SNHL
Heterogenous
Most cases X-linked dominant or recessive

Question 2

What systems does the gene that causes Alport syndrome affect?

Answer 2

Cells of spiral ligament, BM, and stria vascularis of the cochlea
Lens of the eyes
Glomeruli of the kidneys

Question 3

What are some of the kidney problems associated with Alport syndrome?

Answer 3

Blood in urine
Eventual kidney failure and transplant

Question 4

Are there also eye problems associated with Alport syndrome?

Answer 4

Yes
Congenital cataracts and corneal erosion
Retinopathy

Question 5

What are the audiologic findings of Alport syndrome?

Answer 5

Bilateral variable progressive, initially high-frequency SNHL beginning at about the first or second decade of life
Normal vestibular function (except in some cases of the AD form)

Question 6

Do people with Alport syndrome live a long life?

Answer 6

No
Death at ~ 20 to 40 years from hypertension or renal failure

Question 7

What are the 4 criteria for Alport syndrome? (3 of the 4 have to be fulfilled for diagnosis)

Answer 7

Positive family history of hematuria with or without renal failure
Electron microscope evidence of renal disease on renal biopsy
Characteristic opthalmologic signs (in X-linked form, characteristic lens abnormalities and central retinopathy)
High frequency SNHL progressive during childhood

Question 8

What is the prognosis for Alport syndrome?

Answer 8

Variable

Question 9

What is the differential diagnosis for Alport syndrome?

Answer 9

BOR

Question 10

What inheritance pattern does Alport have?

Answer 10

X-linked recessive or dominant