Biochemical Assessment

Question 1

Difference of static and functional test

Answer 1

Static:
• Measure the actual level of nutrient in the specimen
Examples: serum iron, white blood cells, or ascorbic acid level

Functional:
• Determine the sufficiency of host nutriture to permit cells, tissues, organs, anatomical systems, or the host to perform optimally the intended nutrient-dependent biological function
• Aim to measure the extent of the functional consequences of a nutrient deficiency

Question 2

Major limitation of static tests?

Answer 2

Major limitation: recent dietary intake may affect the level

Question 3

What does static tests measure?

Answer 3

1. A nutrient in biological fluids or tissues, or
2. The urinary excretion rate of nutrient or its metabolite

Question 4

Urinary excretion of xanthurenic acid as a test of vitamin B6

Answer 4

Abnormal metabolic products in blood or urine arising from reduced activity of a nutrient-dependent enzyme

Question 5

Hemoglobin for iron status, erythrocyte glutathione reductase for riboflavin

Answer 5

Changes in blood components or change in enzyme activities that depend on a given nutrient

Question 6

Lymphocyte proliferation for protein-energy, zinc and iron

Answer 6

In vitro tests of in vivo functions

Question 7

Tryptophan load test for vitamin B6

Answer 7

Load and tolerance tests and induced responses in vivo

Question 8

Dark adaptation and taste acuity for vitamin A

Answer 8

Spontaneous in vivo responses

Question 9

Sexual maturation for zinc, cognitive performance for iron, iodine, zinc and vitamin B12

Answer 9

Growth or developmental responses

Question 10

What are factors that may confound the results of biochemical tests?

Answer 10

1. Method-related limitations
2. Sampling difficulties
3. Subject-related factors
   4 Health-related factors
4. Biological factors

Question 11

Serrum Ferritin Level is a biochemical test for what stage of Iron Depletion?

Answer 11

Stage 1: depleted iron stores

Question 12

Transferrin saturation and erythrocyte protoporphyrin is a biochemical test for what stage of Iron Depletion?

Answer 12

Stage 2: Iron deficiency with no Anemia

Question 13

Hemoglobin and Mean corpuscular volume is a biochemical test for what stage of Iron Depletion?

Answer 13

Stage 3: Iron-deficiency anemia

Question 14

What is the cutoff value of depleted iron stores for males and females less than 5y of age?

Answer 14

<12 ug/L

Question 15

What is the cutoff value of depleted iron stores for males and females more than 5y of age?

Answer 15

<15 ug/L Serum ferritin level

Question 16

What is the cutoff value of depleted iron stores in presence of infection for males and females less than 5y of age?

Answer 16

<30 ug/L Serum ferritin level

Question 17

What is the cutoff value of severe risk of iron overload for males and females more than 5y of age?

Answer 17

> 200 ug/L Serum ferritin level

Question 18

What percentage of serum transferrin is associated with iron deficiency

Answer 18

<16%

Question 19

What is the cut-off value in defining elevated transferrin receptor level?

Answer 19

> 8.0 ug/L

Question 20

What is the precursor of hemoglobin and becomes elevated when the iron supply is insufficient

It can be used as a screening test in children and adults

Answer 20

Erythrocyte protoporphyrin

Question 21

Reference value of Mean Corpuscular Hemoglobin

Answer 21

24-36 pg

Question 22

Normal range for MCHC

Answer 22

320-360 g/L (32-36 g/dL)

Question 23

Normal range of MCV

Answer 23

80-100 fL

Question 24

Serum retinol concentration of VAD

Answer 24

< 20 ug/dL (0.70 umol/L)

Question 25

VAD is a public health problem if

Answer 25

• >5% or pregnant women with XN or
• >15% of preschool children have VAD

Question 26

Cut-off values for serum concentration of Vit A

Answer 26

20-100 ug/L

Question 27

What Vit A level in breast milk suggests that a child is at risk of VAD?

adeuqate Vit A for growth and development?

nursing child’s body reserve will increase?

Answer 27

< 10 ug/dL

> 20 ug/dL

> 40 ug/dL