C-Reactive Protein (CRP), Serum

CRP is a cytokine-induced, acute-phase protein and is useful in the detection and evaluation of infection, tissue injury, and inflammatory disorders. Plasma levels begin increasing within 4 " “6 hours after initial tissue injury and continue to increase several hundred-folds within 24 " “48 hours. CRP remains elevated during the acute-phase response and returns to normal with restoration of tissue structure and function. The rise in CRP is exponential, doubling every 8 " “9 hours. The half-life is <24 hours.

Normal range: Less than 10 mg/L.

Use

For evaluation of infection, tissue injury, and inflammatory disorders

Provides information for the diagnosis, therapy, and monitoring of inflammatory disorders

Independent risk factor for atherosclerosis, cardiac vascular events, hypertension, and MI

Interpretation

Increased In

Acute inflammation

Rheumatoid arthritis, lupus

Cardiovascular disease, atherosclerosis

Oral contraceptives

Inflammatory bowel disease

Giant cell arteritis

Osteomyelitis

Cancer of the lymph nodes

Pregnancy

Decreased In

Patients treated with carboxypenicillins

Liver failure

Limitations

Elevated C-reactive protein (CRP) values are nonspecific and should not be interpreted without a complete clinical history.

Heterophile antibodies may falsely increase levels.

Elevated levels of CRP are influenced by genetics, age, a sedentary lifestyle, stress, exposure to environmental toxins, and diet that specifically contains refined, processed, and manufactured foods.