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Flashcards in Purine salvage deficiencies Deck (15):
1

What are the two purine salvage deficiencies?

ADA deficiency

Lesch-Nyhan syndrome

2

Mode of inheritance: ADA deficiency

AR

3

What does HGPRT catalyze?

Guanine  --->   GMP

Hypoxanthine  --->  IMP

4

What causes ADA deficiency?

Too much ATP and dATP, which causes feedback inhibition of ribonucleotide reductase, thereby inhibiting pyridimidine synthesis, which decreases pool of rapidly-dividing T cells and B cells

5

What would be elevated in the blood of a kid with Lesch-Nyhan syndrome?

Uric acid

6

Mode of inheritance: Lesch-Nyhan syndrome

X-linked recessive

7

Which drug is activated by HGPRT?

6-MP

 

(inhibits PRPP  --->  IMP in purine synthesis)

8

What does xanthine oxidase catalyze?

Hypoxanthine  -->  xanthine

Xanthine  -->  uric acid

9

What are the symptoms of Lesch-Nyhan syndrome?

Hyperuricemia

Gout

Pissed (agitation, self-mutilation)

Retardation

dysTonia

10

Which drug produces the same deficiency as ADA deficiency?

Hydroxyurea

 

(Both cause inhibition of ribonucleotide reductase)

11

What does ADA catalyze?

Adenosine  --->  inosine

12

What causes Lesch-Nyhan syndrome?

HGPRT deficiency, so can't generate IMP or GMP

13

How is Lesch-Nyhan syndrome treated?

Allopurinol or febuxostat

14

ADA deficiency is the primary cause of:

SCID

15

Which drug in inactivated by XO (and TMPT)?

6-MP

 

(inhibits PRPP  --->  IMP in purine synthesis)