Acute-phase proteins are often used as a marker of the stress response

Question

What is an acute-phase protein? What is the role of C-reactive protein in the nutritional assessment of critically ill trauma patients? What other acute-phase proteins may be followed to assess the inflammatory stress response?

Answer 1

An acute-phase protein is a protein whose plasma concentration increases or decreases at least 25% during an inflammatory condition. They are classified as positive acute phase proteins (ones that increase) or negative acute phase proteins (ones that decrease). Positive acute phase proteins include CRP, hepcidin, ferritin, and complement. Negative acute phase proteins include albumin, transthyretin, retinol binding protein Cytokines and other molecules within the immune system regulate the release of acute-phase proteins. CRP levels are the most commonly measured positive acute phase protein and any elevation indicates an inflammatory process is occurring. However, CRP is nonspecific and could be indicative of almost any inflammatory condition including obesity, type 2 diabetes, cardiovascular disease etc. It is not specific to trauma or metabolic stress.. When IL-6 increases,the production of albumin and prealbumin decreases, so when assessing a patient's lab values, it is important to look at all three values for an indication of inflammatory response. Other positive acute-phase proteins include fibronectin, ceruloplasmin, and serum amyloid A.