Interpretive Handbook

Test 82047 :
C-Reactive Protein, High Sensitivity, Serum

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

C-reactive protein (CRP) is a sensitive acute-phase reactant. Plasma CRP levels can increase dramatically (100-fold or more) after severe trauma, bacterial infection, inflammation, surgery, or neoplastic proliferation. Measurement of CRP has been used historically to assess activity of inflammatory disease, to detect infections after surgery, to detect transplant rejection, and to monitor these inflammatory processes. While assays for CRP have been available for many years, the traditional assays lack the sensitivity to measure basal levels of CRP.


High-sensitivity CRP (hs-CRP) can accurately measure basal levels of CRP throughout the currently accepted cardiovascular risk assessment range (0.20-10.0 mg/L). A large prospective clinical trial demonstrated significantly less cardiovascular risk for patients with hs-CRP <2.0 mg/L.(1) Several guidelines now recommend hs-CRP be measured in moderate-risk patients or cases where additional risk assessment is desired.(2-4) More aggressive treatment strategies may be warranted in patients with hs-CRP > or =2.0mg/L.

Useful For Suggests clinical disorders or settings where the test may be helpful

Assessment of risk of developing myocardial infarction in patients presenting with acute coronary syndromes


Assessment of risk of developing cardiovascular disease or ischemic events in individuals who do not manifest disease at present

Interpretation Provides information to assist in interpretation of the test results

Increased high-sensitivity C-reactive protein values are associated with increased risks of cardiovascular disease and cardiovascular events.

Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

This test is recommended for cardiovascular risk assessment only.


C-reactive protein (CRP) is an acute-phase reactant and has high intraindividual variability. Therefore, a single test for high-sensitivity CRP (hs-CRP) may not reflect an individual patient's basal hs-CRP level. Repeat measurement may be required to firmly establish an individual's basal hs-CRP concentration. The lowest of the measurements should be used as the predictive value.


Because CRP is an acute-phase reactant, measurements in apparently healthy individuals may not truly reflect the basal level if inflammation is present.


This hs-CRP assay should be used as a means to assess risk of cardiovascular disease or events. A different CRP test (CRP / C-Reactive Protein [CRP], Serum) should be used to monitor or assess other inflammatory disorders.

Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

Lower risk: <2.0 mg/L

Higher risk: > or =2.0 mg/L

Acute inflammation: >10.0 mg/L

Clinical References Provides recommendations for further in-depth reading of a clinical nature

1. Ridker PM, Danielson E, Fonseca FA, et al: Reduction in C-reactive protein and LDL-cholesterol and cardiovascular event rates after initiation of rosuvastatin: a prospective study of the JUPITER trial. Lancet 2009;373:1175-1182

2. European Association for Cardiovascular Prevention and Rehabilitation, Reiner Z, Catapano AL, et al: ESC/EAS Guidelines for the management of dyslipidaemias: the Task Force for the management of dyslipidaemias of the European Society of Cardiology (ESC) and the European Atherosclerosis Society (EAS). Eur Heart J 2011;32:1769-1818

3. Goff DC, Lloyd-Jones DM, Bennett G, et al: 2013 ACC/AHA Guideline on the Assessment of Cardiovascular Risk. Circulation 2014;129:S49-S73

4. Jacobson TA, Ito MK, Maki KC, et al: National Lipid Association recommendations for patient-centered management of dyslipidemia: part 1 - executive summary. J Clin Lipidol 2014;8:473-488