Serum Protein Measurement in Clinical Practice

Introduction to Serum Protein Measurement

The American Journal of Kidney Diseases recommends serum protein measurements as complementary tools to assess nutritional status, predict clinical outcomes, and identify inflammation, with lower levels associated with higher risk of hospitalization and mortality, particularly in patients with chronic conditions such as kidney disease 1

Serum albumin is a powerful predictor of illness and death in patients with end-stage kidney disease (ESKD) and serves as a useful indicator of protein-energy nutritional status, according to the American Journal of Kidney Diseases 2, 3
Serum prealbumin can be more sensitive to rapid changes in nutritional status due to its shorter half-life, as noted by the American Journal of Kidney Diseases 2, 4
The American Journal of Kidney Diseases states that serum proteins help identify patients at risk for protein-energy wasting (PEW), with serum albumin <3.5 g/dL associated with higher odds of mortality 1
Glycated serum proteins provide an index of glycemic status over a shorter period, making them useful in situations where A1C may not be reliable, as reported in Diabetes Care 5

The American Journal of Kidney Diseases advises that serum proteins should not be interpreted in isolation as they are influenced by non-nutritional factors including inflammation, hydration status, protein losses, and acidemia 1, 2, 4
During inflammation, serum albumin and prealbumin decrease as negative acute-phase reactants, while positive acute-phase proteins increase, according to the American Journal of Kidney Diseases 2, 4

The American Journal of Kidney Diseases recommends that for maintenance dialysis patients, a predialysis or stabilized serum albumin equal to or greater than the lower limit of normal range is the outcome goal 3
Serum albumin <3.0 g/dL is associated with increased risk of surgical complications, as noted by the American Journal of Kidney Diseases, although this fact is also reported by Praxis Medical Insights, the American Journal of Kidney Diseases is the preferred source 6 is not used, instead: The American Journal of Kidney Diseases states that serum albumin is a predictor of surgical complications 1
Routine monitoring of serum albumin is recommended monthly in dialysis patients, according to the American Journal of Kidney Diseases 3, 7
Serum prealbumin <30 mg/dL should trigger evaluation for protein-energy malnutrition, as reported by the American Journal of Kidney Diseases 4

The American Journal of Kidney Diseases recommends using serum proteins as part of a comprehensive nutritional assessment that includes other measures such as body weight assessment, subjective global assessment, dietary interviews, and normalized protein catabolic rate (nPCR) 7
The American Journal of Kidney Diseases and Diabetes Care suggest that serum proteins should be used in conjunction with other nutritional parameters to accurately assess nutritional status, as GSP values can vary with changes in the synthesis or clearance of serum proteins during acute illness or liver disease 1, 5, 7