Lab Values

Question 1

Transthyretin

Prealbumin

Answer 1

TTHY
PAB
16-40 mg/dl
Short half-life; picks up changes in protein status quickly

Question 2

Retinol-binding protein

Answer 2

RBP
3-6 mg/dl
Circulates with prealbumin
Shortest half-life (12 hrs)
Binds and transports retinol

Question 3

Serum albumin

Answer 3

3.5-5.0 g/dl
maintains colloidal osmotic pressure
hypoalbuminemia associated with edema
levels above normal range likely due to dehydration
long half-life, does not reflect current protein intake

Question 4

Serum transferrin

Answer 4

> 200 mg/dl visceral protein
serum level controlled by iron storage pool
rises with iron deficiency
can be determined from TIBC- total iron binding capacity

Question 5

Hematocrit

Answer 5

Hct
Men 44%
Women 38%
Pregnant women 33%
volume of packed cells in whole blood

Question 6

Hemoglobin

Answer 6

Hb
Men 14-17 gm/ dl
Women 12-15 gm/dl
Pregnant < or = 11
iron-containing pigment of red blood cells
erythrocytes are produced in bone marrow

Question 7

Serum ferritin

Answer 7

Women 10-150 ng/ml
Men 12-300 ng/ml
indicates size of iron storage pool

Question 8

Serum creatinine

Answer 8

0.6-1.4 mg/dl
related to muscle mass; measures somatic protein
may indicate renal disease, muscle wastage

Question 9

Creatinine height index

Answer 9

CHI
80% normal
ratio of creatinine excreted per 24 hrs to height
estimates lean body mass- somatic protein
60-80% mild muscle depletion

Question 10

Blood urea nitrogen

Answer 10

BUN
10-20 mg/dl
related to protein intake
indicator of renal disease
BUN: creatinine ratio - normal 10-15: 1

Question 11

Urinary creatinine clearance

Answer 11

115 + or - 20 ml / minute

measures GFR - glomerular filtration rate, renal function

Question 12

Total lymphocyte count

Answer 12

TLC
>2700 cells/cu m
measures immunocompetency
moderate depletion 900-1800, severe depletion <900
decreased in protein-energy malnutrition

Question 13

C-reactive protein

Answer 13

CRP
Marker of acute inflammatory distress
as it declines, indicates when nutritional therapy would be beneficial

Question 14

Free erythrocyte protoporphyrin

Answer 14

FEP
direct measure of toxic effects of lead on heme synthesis
Increased in lead poisoning
lead depletes iron leading to anemia, and displaces calcium in the bone leading to a zinc deficiency

Question 15

Prothrombin time

Answer 15

PT
11.0-12.5 seconds; 85-100% of normal
anticoagulants prolong PT
evaluates clotting adequacy; change in vitamin K intake will alter rate