Serum protein is a measurement of the total amount of protein in a blood sample. In healthy individuals, proteins make up around seven percent of the blood volume. They perform a number of important functions from regulating clotting activity to providing immunity. Changes in serum protein can be indicative of health problems and may provide important diagnostic clues to a physician attempting to learn why a patient is having a medical problem.
For a serum protein test, a blood sample is drawn from the patient. Several tubes of blood may be taken to enable the performance of other laboratory tests. Patients who are nervous about having blood drawn may want to ask the technician ahead of time about how many vials will be drawn, and can find it helpful to eat a light snack beforehand and to look away while the blood is drawn. The samples will be sent to a lab for analysis.
Several lab techniques can be used to determine serum protein. Two proteins in the blood, globulin and albumin, are of particular interest. They typically make up the bulk of the protein in the blood and the ratio between the two should remain relatively consistent. Changes in the ratio can be caused by many health conditions. Some conditions linked with changes in serum protein include: dehydration, diabetes, heart failure, kidney disease, tuberculosis, liver disease, autoimmune disease, and blood diseases like leukemia.
Normal serum protein is around six to eight grams per decaliter, sometimes expressed as 60 to 80 grams per liter. If the values are abnormal, additional testing may be needed to find out why. While diagnosing a patient with skewed serum protein values, a doctor will consider information reported by the patient along with data from other medical tests and observations made during exams. Other blood chemistry analysis can also provide important information such as abnormal levels of liver enzymes in people with liver disease.
Doctors can order a serum protein screening as part of a routine physical, in response to a specific concern, or as part of a follow up plan for monitoring a patient who is being treated for disease. Long term monitoring of patients can be useful for seeing how well they respond to treatment. It may be necessary to adjust a treatment protocol to address changes in patient response or to help a patient comply with medications and other medical orders more easily.