Pediatric Nutrition in Practice

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Use of Laboratory Measurements in Nutritional Assessment 25

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Table 1 (continued)


Test (specimen) Normal range^1 Function/description Deficiency Pitfalls to avoid


Hemoglobin
(whole blood)


0 – 8 days: 2.06 – 3.79 mmol/l
9 days: 1.66 – 3.33 mmol/l
3 months: 1.53 – 2.25 mmol/l
1 year: 1.38 – 2.14 mmol/l
3 years: 1.58 – 2.31 mmol/l
11 years: 1.72 – 2.43 mmol/l
Adult male: 1.86 – 2.48 mmol/l
Adult female: 2.17 – 2.79 mmol/l

Oxygen-carrying moiety
in RBC

Microcytic
Iron deficiency, chronic
disease
Normocytic
Chronic disease, acute
bleeding
Macrocytic
B 12 , folate deficiency

Influenced by hydration status,
nutrition and pregnancy

Iron (serum) Neonate: 17.9 – 44.8 μmol/l
Infant: 7.2 – 17.9 μmol/l
Child: 9 – 21.5 μmol/l
Adult male: 11.6 – 31.3 μmol/l
Adult female: 9 – 30.4 μmol/l


Component in heme and
cytochrome proteins

Microcytic anemia, pallor,
weakness and dyspnea

Transferrin is a sensitive
measure of body iron stores;
however, it is a negative
acute-phase protein

Lymphocytes
(whole blood)


>1,500/mm^3 Total lymphocyte count is
inversely correlated to degree
of malnutrition [6]

Magnesium
(serum)


0.63 – 1.00 mmol/l Important for neuromuscular
conduction; enzyme cofactor

Arrhythmia, tetany,
hypocalcemia and
hypokalemia

↓ by low serum albumin
↑ by hemolyzed specimens

pH (stool) >5.5 [7] Low fecal pH usually implies
carbohydrate malabsorption


Improper specimen processing
may lead to falsely low values

Phosphorus
(serum)


Neonate: 1.45 – 2.91 mmol/l
10 days to 2 years: 1.29-2.1 mmol/l
3 – 9 years: 1.03 – 1.87 mmol/l
10 – 15 years: 1.07 – 1.74 mmol/l
>15 years: 0.78 – 1.42 mmol/l

Vital for energy transfer at
cellular level

Confusion, respiratory distress,
tissue hypoxia, bone
abnormalities and ↑ alkaline
phosphatase

‘Refeeding syndrome’ is
hypophosphatemia and
hypokalemia complicating
nutritional rehabilitation of the
severely malnourished patient

Prealbumin
(serum)


Neonate: 70 – 390 mg/l
1 – 6 months: 80 – 340 mg/l
6 months to 4 years: 120 – 360 mg/l
4 – 6 years: 120 – 300 mg/l
6 – 19 years: 120 – 420 mg/l

Gauge of visceral protein
stores; half-life of 2 days

Negative acute-phase reactant

Prothrombin
time (plasma)


11 – 15 s [2] Used to assess vitamin K
sufficiency, although
better assessed with
undercarboxylated
prothrombin (PIVKA-II)

Also prolonged in liver
dysfunction, malabsorption
syndromes, prolonged
antibiotic use and warfarin
therapy

Reducing
substances
(stool)


Negative Presence suggests carbo-
hydrate malabsorption

Improper specimen processing
may lead to falsely normal
values

Retinol-binding
protein (serum)


<9 years: 10 – 78 mg/l
>9 years: 13 – 99 mg/l [2]

Gauge of visceral protein
stores; half-life of 12 h

Negative acute-phase reactant
↓ in vitamin A deficiency,
hepatic dysfunction
↑ in renal failure

Selenium
(serum)


Preterm: 0.6 – 1 μmol/l
Term: 0.8 – 1.1 μmol/l
1 – 5 years: 1.4 – 1.7 μmol/l
6 – 9 years: 1.4 – 1.8 μmol/l
>10 years: 1.6 – 2.1 μmol/l [5]

Trace mineral essential for
glutathione peroxidase

Cardiomyopathy (Keshan
disease), myositis and nail
dystrophy

Urea nitrogen
(serum)


Preterm (1st week): 1.1 – 8.9 mmol/l
Neonate: 0.7 – 6.7 mmol/l
Infant/child: 1.8 – 6.4 mmol/l
Adult: 2.1 – 7.1 mmol/l

Produced in liver from
protein degradation and
excreted renally

↓ in low-protein-intake states
↑ in high-protein diets, but also
kidney disease

Koletzko B, et al. (eds): Pediatric Nutrition in Practice. World Rev Nutr Diet. Basel, Karger, 2015, vol 113, pp 23–28
DOI: 10.1159/000360314
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