Cystinuria

Question 1

Inheritance

Answer 1

autosomal recessive disorder

Question 2

Main features of cysteinuria

Answer 2

recurrent renal stones

yellow and crystalline, appearing semi-opaque on x-ray

Question 3

Defect in membrane transport of which compounds?

Answer 3

cystine
ornithine
lysine
arginine

(mnemonic = COLA)

Question 4

Which chromosomes are affected in cysteinuria?

Answer 4

chromosome 2: SLC3A1 gene, chromosome 19: SLC7A9

Question 5

What investigation is used for diagnosis of this condition?

Answer 5

cyanide-nitroprusside test

Question 6

Management of cysteinuria?

Answer 6

hydration
D-penicillamine
urinary alkalinization (potassium citrate)