Protein

Keywords: Total protein, TP

Specimen:

5 mL blood in plain or lithium heparin tube, avoiding excessive venous stasis.

Method:

Spectrophotometry.

Reference Interval:

Neonate: 40-75 g/L

Child < 2 years: 50-75 g/L

Adult:  See Table 6.

Posture influences levels, recumbent levels are approximately 10-15% lower.

Application:

Used in conjunction with albumin to calculate globulin.

Diagnosis and monitoring of hyper- and hypo-gammaglobulinaemia, protein losing states and malnutrition.

In most situations specific protein assay is required.

See Albumin and Globulins.

Interpretation:

Depends on the levels of albumin and immunoglobulins, which are the only proteins present in serum in sufficient concentration to significantly alter total protein levels. Increased levels also occur after excessive venous stasis during blood collection and in dehydration.

Reference:

Silverman LM and Christenson RH. In: Curtis CA and Ashwood ER eds. Tietz Textbook of Clinical Chemistry. 2nd ed. 1994. WB Saunders.