C-Reactive Protein (CRP) Cat.#HK358 is an acute-phase protein, produced exclusively in the liver.
ELISA for Quantitative Determination of CRP in Human Serum and Plasma
CRP is present in the serum of normal persons at concentrations ranging up to 5mg/l.
CRP and diseases
• A marker for acute inflammation and tissue necrosis. Within 6 hours of an acute inflammatory challenge the CRP level starts to rise.
• Serum concentration of CRP increases significantly in cases of both infectious and non-infectious inflammation, of tissue damage and necrosis and in the presence of malignant tumors.
• CRP is present in the active stages of inflammatory disorders like rheumatoid arthritis, ankylosing spondylitis, Reiter's syndrome, psoriatric arthropathy, systemic lupus erythematosus, polyarteritis, ulcerative colitis and Crohn's disease.
• Injuries causing tissue breakdown and necrosis are associated with increases in serum CRP which are seen in thermal burns, major surgery and myocardial infarction.
• Widespread malignant disease with carcinoma of the lung, stomach, colon, breast, prostate and pancreas, Hodgkin's disease, non-Hodgkin's lymphoma and lymphosarcoma will give rise to high levels of CRP resulting from tissue damage by invading tumour cells.
• The CRP-level increases dramatically following microbial infections, and this may be particularly helpful for the diagnosis and monitoring of bacterial septicemia in neonates and other immunocompromised patients at risk.
• In children, CRP is useful for differential diagnosis of bacterial and viral meningitis
• Because the biological half-life of this protein is only 24 hours, CRP accurately parallels the activity of the inflammation process and the CRP concentration decreases much faster than ESR or any other acute phase parameter, which is particularly useful in monitoring appropriate treatment of bacterial diseases with antibiotics.
• C-Reactive Protein measurements during the early and late post transplant period of bone marrow and organ transplantations is particularly useful in the management of interfering infections in these immunosuppressed patients.
Examples of typical OD values:
CALIBRATOR
µg/ml O.D. value
0 0.019
5 0.240
25 0.821
50 1.301
100 2.018
All individuals have small amounts of CRP in their blood. The upper limit of the normal range is situated between 5 and 8 µg/ml.
Precision
Intra Assay (n=10) Level 1 Level 2
Mean (µg/ml) 5.20 48.3
SD (µg/ml) 0.27 3.30
%CV 5.12 6.84
Inter Assay (n=7) Level 1 Level 2 Level 3
Mean (µg/ml) 4.30 31.0 67.2
SD (µg/ml) 0.60 3.60 8.50
%CV 14.3 11.6 12.7
Minimal detectable concentration is <1 µg/ml.
References
1. Powell L. J. C-Reactive Protein - a Review Am. J. Med. Technol., 1979, 87: 138
2. Gewurz H., Mold C., Siegel J. and Fiedel B. C-Reactive Protein and the Acute Phase Response Advances in Internal Medicine, 1982, 27:345
3. Helgeson N. G. P., Adamson D. M., Pike R. B., James D. S., Nicodemus D. S., Lee B. A. and Miller G. W. C-Reactive Protein : Laboratory Medicine, Vol. 2 (Race G. J., Ed.), Harper & Row, Hagerstown, chapter 29 (1973).
4. Johnson HL., Chiou CC., Cho CT. Applications of acute phase reactants in infectious diseases J. Microbiol. Immunol. Infect. 1999, 32:73