Total protein measures the combined concentration of albumin and globulins in the blood. These proteins perform essential functions including maintaining blood osmotic pressure, transporting hormones and nutrients, fighting infection, and supporting blood clotting. The liver is the primary site of protein synthesis.
Interpreting total protein alongside the albumin-to-globulin ratio provides useful clinical information. Low total protein may indicate malnutrition, liver disease, kidney disease (protein loss in urine), or malabsorption. High total protein is most commonly caused by elevated globulins, which can occur in chronic inflammation, autoimmune disease, or plasma cell disorders such as multiple myeloma.
FAQs
What is the albumin-to-globulin ratio?
The A:G ratio is albumin divided by globulins (total protein minus albumin). A normal A:G ratio is above 1.2. Low A:G ratio (below 1.0) suggests elevated globulins from inflammation, autoimmune disease, or paraprotein. High A:G may suggest low globulin production.
What causes very high total protein?
Very high total protein (above 90-100 g/L) is strongly suggestive of a paraprotein disorder such as multiple myeloma or Waldenstrom's macroglobulinaemia. Protein electrophoresis and immunofixation are required to characterise the abnormal protein.
Can dehydration affect total protein?
Yes. Dehydration concentrates the blood, raising both albumin and globulin levels and increasing measured total protein. Ensuring good hydration before blood tests improves accuracy.
Is total protein the same as albumin?
No. Total protein includes albumin (typically 35-50 g/L) plus globulins (immunoglobulins and other proteins). Albumin is the dominant component and the most clinically useful individual protein marker.
