Globulin
What it measures, and what changes the number.
Globulin is the portion of total serum protein that is not albumin. It includes antibodies (immunoglobulins), transport proteins and many proteins involved in inflammation and clotting. On most chemistry panels it is not measured directly but calculated by subtracting albumin from total protein.
It is read with total protein, albumin and the albumin/globulin ratio on a comprehensive metabolic panel. When a more detailed picture is wanted, serum protein electrophoresis splits globulin into alpha, beta and gamma fractions, and individual immunoglobulins such as IgG can be measured.
Since it is derived from two assays, the albumin method used (bromocresol green or bromocresol purple) can shift the calculated globulin. A long tourniquet time or posture during the draw can concentrate proteins in the sample. Labs may print it as GLOBULIN, Total globulin or Globulins.
Often read alongside: Total protein, Albumin, Albumin/globulin ratio, Gamma globulin, IgG