Plasma Cholinesterase Abnormalities

Question 1

What is plasma cholinesterase (PC)

Answer 1

An enzyme found in PLASMA and most TISSUES, but NOT in rbcs.

Question 2

What does PC degrade

Answer 2

acetylcholine
succinylcholine
Ester-linked LA
Cocaine
Mivacurium
Pilocarpine
Donepezil

Question 3

How is PC transmitted

Answer 3

Autosomal recessive

Question 4

What chromosome is PC associated with

Answer 4

chromosome 3q26

Question 5

What type of variant is assoc. with PC

Answer 5

Atypical

Question 6

What aa change is noted for PC

Answer 6

70 Aspartine replaced by Glycine

Question 7

What is the name of the test used to determine if a patient has PC

Answer 7

Dibucaine Number

Question 8

How does the Dibucaine test work

Answer 8

The aa Dibucaine will inhibit the NORMAL PC activity by 80% in disease-free patients

The aa Dibucaine will inhibit ABNORMAL PC by only 20%

Question 9

True/False

The Dibucaine test measures activity parameters such as PC plasma concentration and enzyme efficiency

Answer 9

FALSE

Question 10

What is the genotype for someone with PC deficiency

Answer 10

EaEa

Question 11

Some genetic variations are inhibited by

Answer 11

Fluoride

Question 12

What are the genotypes for fluoride deficiencies

Answer 12

Ef

Es

Question 13

What isoenzyme variant of PC results in abnormally rapid hydrolysis of succs

Answer 13

C5 variant

Question 14

What is the Porphyrias

Answer 14

The porphyrias are a group of rare inherited or acquired disorders of certain enzymes that normally participate in the production of porphyrins and heme

porphyrins are the main precursors of heme, an essential constituent of hemoglobin, myoglobin, catalase, peroxidase, respiratory and P450 liver cytochromes.

Question 15

What are the two categories of porphyrias

Answer 15

hepatic

erthropoietic

Question 16

Hepatic porphyrias are further classifed into which four conditions

Answer 16

**Acute intermittent prophyria
Porphyria cutanea tarda
Variegate porphria
Hereditary coproporphyria

Question 17

Which hepatic porphyria is the most important and serious form

Answer 17

Acute intermittent porphyria

Question 18

In AIP deficiency of uroporphyrinogen I synthetase results in

Answer 18

excess formation of porphobilinogen and simga-aminolevulinate which accumulates in the urine

Question 19

The clinical manifestations of AIP include

Answer 19

SEVERE abdominal pain in young-middle aged females
*mistaken for acute cholecystitis, pancreatitis, appendicitis, or renal colic

Demyelination»motor weakness, ANS dysfunction, emotional disturbances, psychosis, paralysis of resp. muscles

Question 20

What events trigger attacks

Answer 20

starvation
dehydration
sepsis
female hormones
drugs

Question 21

What drug classifications are known to precipitate porphyria

Answer 21

sedative/hypnotics-barb,ket,eto,benz
analgesics-lidocaine
anticonvulsants-phenytoin
antibiotics-sulfa drugs
steroids-Estrogen, Progesterones, corticost.
toxins-ethanol, lead, amphetamines

Question 22

GIve —– and —— only for patients with porphyria

Answer 22

opioids and propofol

Question 23

Treatment of acute attacks of AIP

Answer 23

Hydration
Glucose infusion
Hematin infusion
Analgesia