CRP test measures the amount of C-reactive proteins in your blood. It is a type of protein produced in your liver in response to any inflammation or tissue damage in your body. A healthy body produces low levels of CRP (<4 mg/L). Higher levels of CRP indicate an underlying infection or disease such as bacterial, fungal & viral infections, inflammatory bowel disease, autoimmune disorders such as rheumatoid arthritis or lupus, cancer etc. However, keep in mind that the CRP test only indicates general inflammation in the body. It doesn't pinpoint any specific disease. In case your C-reactive protein levels are high, the doctor will prescribe additional tests to diagnose your particular condition.