Protein, Blood, Total and Fractions and Protein, Urine

General

Synonym/Acronym:
TP, SPEP (fractions include albumin, alpha1-globulin, alpha2-globulin, beta-globulin, and gamma-globulin).

Rationale
Blood: To assess nutritional status related to various disease and conditions such as burns, edema, dehydration, and malabsorption. Urine: To assess for the presence of protein in the urine toward diagnosing disorders affecting the kidneys and urinary tract, such as cancer, infection, and pre-eclampsia.

Patient Preparation
There are no food, fluid, activity, or medication restrictions unless by medical direction. For urine studies, usually a 24-hr urine collection is ordered. As appropriate, provide the required urine collection container and specimen collection instructions.

Normal Findings
Method: Blood and Urine: Spectrophotometry for total protein, electrophoresis for protein fractions.


Blood: Total Protein
AgeConventional UnitsSI Units (Conventional Units × 10)
Newborn–5 days3.8–6.2 g/dL38–62 g/L
1–3 yr5.9–7 g/dL59–70 g/L
4–6 yr5.9–7.8 g/dL59–78 g/L
7–9 yr6.2–8.1 g/dL62–81 g/L
10–19 yr6.3–8.6 g/dL63–86 g/L
Adult6–8 g/dL60–80 g/L
Values may be slightly decreased in older adults due to insufficient intake or the effects of medications and the presence of multiple chronic or acute diseases with or without muted symptoms.

Blood: Protein Fractions
Conventional UnitsSI Units (Conventional Units × 10)
Albumin3.4–4.8 g/dL34–48 g/L
alpha1-Globulin0.2–0.4 g/dL2–4 g/L
alpha2-Globulin0.4–0.8 g/dL4–8 g/L
beta-Globulin0.5–1 g/dL5–10 g/L
gamma-Globulin0.6–1.2 g/dL6–12 g/L
Values may be slightly decreased in older adults due to insufficient intake or the effects of medications and the presence of multiple chronic or acute diseases with or without muted symptoms.

Normal 24-Hour Urine Volume
The ranges are very general averages and were not calculated on the basis of normal average body weights. Literature shows that the expected urinary output can be estimated by formula where the expected output is as follows:
  • Infants: 1–2 mL/kg/hr
  • Children and adolescents: 0.5–1 mL/kg/hr
  • Adults: 1 mL/kg/hr
Newborns15–60 mL
Infants
  3–10 days100–300 mL
  11–59 days250–450 mL
  2–12 mo400–500 mL
Children and adolescents
  13 mo–4 yr500–700 mL
  5–7 yr650–1,000 mL
  8–14 yr800–1,400 mL
Adults and older adults800–2,500 mL (average 1,200 mL)
Normally, more urine is produced during the day than at night. With advancing age, the reverse will often occur. The total expected outcome for adults appears to remain the same regardless of age.
24-Hr Total Urine ProteinConventional UnitsSI Units (Conventional Units × 0.001)
Normal excretion30–150 mg/24 hr0.03–0.15 g/24 hr
ProteinuriaGreater than 300 mg/24 hrGreater than 0.3 g/24 hr
The 24-hr urine volume is recorded and provided with the results of the protein measurement. Electrophoresis for fractionation is qualitative: No monoclonal gammopathy detected. (Urine protein electrophoresis should be ordered along with serum protein electrophoresis.)
Spot or Random Urine Protein/Creatinine Ratio—useful in situations where 24-hr urine collection is not feasible (e.g., urgent such as with pre-eclampsia, patients unable to reliably cooperate such as pediatric patients, etc.)
AgeMaleFemale
7–9 yr61–220 mg/g70–548 mg/g
10–12 yr59–220 mg/g57–334 mg/g
13–15 yr41–371 mg/g33–307 mg/g
16–17 yr31–242 mg/g36–329 mg/g
Greater than 17 yr15–68 mg/g10–107 mg/g

Critical Findings and Potential Interventions
N/A

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