C reactive Protein Test

C reactive protein is an acute phase reactant produced by the liver as an inflammatory response because of an infection. C reactive protein determination detects the presence of inflammation in the body. C-reactive protein values are very significant in determining the possibilities of long term diseases such as myocardial infarction, neoplastic proliferation and also some inflammatory diseases caused due to infection. C-reactive protein is also considered as the scavenger protein. It binds to many microorganisms in facilitating the process of cell mediated cytotoxicity and also phagocytosis.

C reactive protein test is advised to patients who undergo surgeries pertaining to both general and transplantation categories. It enables in determining the underlying causes of graft rejection. The general CRP determination is of less significance as the values obtained may not describe the underlying health conditions in a specific way. This diagnostic obligation pertaining to the exact values of CRP is eliminated with the introduction of highly sensitive C-reactive protein test (HsCRP).

Principle of the Hs-CRP test

Highly sensitive CRP test is ordered especially in the diagnosis of cardiovascular disease. Hs-CRP test is done using the enzyme linked immunosorbent assay (ELISA). The procedure involves the use of a unique monoclonal antibody which is targeted against a distinct antigenic determinant on the CRP. The CRP molecules in the test sample are sandwiched between the monoclonal antibody which forms the solid phase for immobilization in the test and the enzyme linked antibodies.

Physiology and clinical manifestations

The CRP levels in the body significantly increase after 24 to 48 hours as a response to indicate the onset of tissue damage. These values may remain constant for a longer duration before they reach the normal values. The American Heart Association and the Center for Disease Control have determined the risk groups based on the CRP values. Patients with CRP value less than 1mg/L fall under the low risk groups and values ranging from 1 to 3 mg/L indicate the patients fall under average and high risk groups for cardio vascular disease.

The values of high sensitivity C reactive protein test are part of cardiovascular disease diagnosis. These values are further correlated with other important parameters such as cholesterol levels and glucose levels. Careful analysis is required to understand the history of the patient before the test. This analysis includes a previous history of smoking, infectious disease, alcoholism etc. The hsCRP level values vary if the patient has previously taken non steroidal anti inflammatory drugs. High sensitivity CRP ratios have exceptions in clinical conditions such as arthritis because of the high inflammatory response seen in these conditions. The values are not taken into consideration under these conditions. Coronary artery disease related conditions are predicted in healthy individuals through the hsCRP test.

This Hs CRP test serves as an effective marker in identifying the risk for coronary artery related stroke or heart attack in a healthy individual. The hs-CRP test is also used in the detection of colon cancer and complications related to diabetes and obesity. The hs-CRP test is increasingly becoming an effective test in the pharmacological management of patients by the clinicians as it gives details for the precise use of statins and anti thrombotic medications. Research pertaining to the comparative ratio drawn between patients having high CRP values and low LDL (low density lipoproteins) values prove that these patients are at greater risk of developing cardiovascular disease. These studies conclude that the hs-CRP test is a significant marker in prediction of asymptomatic cardiovascular disease among healthy individuals. The hs-CRP test is also effective in the determination of HNF1A mutations which act as the precursor for the maturity onset diabetes of the young (MODY). This helps in the screening of unidentified diabetes.