You may get this test as part of a comprehensive metabolic panel, which is often included in a routine checkup. You may also need this test if you have symptoms that indicate abnormal protein levels. These include:
Swelling in the feet, ankles, legs, and/or abdomen, which is caused by extra fluid in your tissues
Fatigue
Unexplained weight loss
Loss of appetite
Jaundice  (yellowing of the skin or eyes). This is a common symptom of liver disease.
Blood in the urine, a common symptom of kidney disease