Chapter 8: 1.4 - Cystine Disorder

Question 1

• has noticeable odor of sulfur

Answer 1

Cystinuria

Question 2

-elevated cystein

2 modes of inheritance of this disease

Answer 2

Cystinuria

1. reabsorption problem of all - four amino acids (cystine, lysine, arginine, ornithine)
2. only cystine and lysine are not reabsorbed

Question 3

Cystinuria:

- more probable stone formers of the 2 modes of inheritance

Answer 3

4 amino acid reabsorption problem

Question 4

Cystinuria tests:

- recommended specimen

Answer 4

first morning specimen

Question 5

Cystinuria tests:

1

Answer 5

cyanide- nitroprusside

Question 6

Cystinuria tests:
cyanide-nitroprusside
color
-false positive

Answer 6

red-purple

- presence of ketones and homocystine

Question 7

Cystine Disorders: (3)

Answer 7

1. Cystinuria
2. Cystinosis
3. Homocystinuria

Question 8

-defect in the lysosomal membranes which prevents the release of cystine into the cellular cytoplasm for metabolism

Answer 8

Cystinosis

Question 9

• incomplete metabolism of cystine
  -results: deposite of cystine in:
  corena, bone marrow, lymph nodes, internal organs

Answer 9

Cystinosis

Question 10

• routine lab findings in infantile nephropathic cystinosis

Answer 10

1. polyuria
2. aminoaciduria
3. positive test for reducing substance
4. isothenuria
   severe disorder:
5. photophobia
6. renal failure
7. rickets
8. growth failure

Question 11

Cystinosis general categories:

2

Answer 11

1. Nephropathic

2. Nonnephropathic - benign, can cause ocular diorder

Question 12

Cystinosis Test: (2)

Answer 12

1. cyanide-nitroprusside

2. Clinitest

Question 13

Cystinuria tests:
cyanide-nitroprusside
color

Answer 13

red-purple

Question 14

Cystinuria tests:

clinitest

Answer 14

orange-red

Question 15

• intermediate amino acid in the syntesis of cystein from methionine

Answer 15

Homocystinuria

Question 16

Homocystinuria enzyme deficiency

Answer 16

liver enzyme

cystathionine B-synthase

Question 17

• newborns = no abnormalities

- gradual physical defects with aging

Answer 17

Homocystinuria

Question 18

• osteoporosis
• dislocated lenses in the eyes
• thrombosis

Answer 18

Homocystinuria

Question 19

Homocystinuria test:

3

Answer 19

1. newborn screening - mod. Guthrie
2. Cyanide-nitropruside
3. silver nitroprusside

Question 20

Homocystinuria test:
Cyanide-nitroprusside
color
specificity

Answer 20

red-purple

nonspecific

Question 21

Homocystinuria test:
sliver nitroprusside
color
specificity

Answer 21

red purple
-follow-up test after positive cyanide-nitropruside
=fresh urine should be used