C-reactive protein (CRP)a. Is secreted in a circadian rhythm with higher levels in the morning
The acute phase proteins are nonspecific biochemical markers produced by hepatocytes in response to tissue injury, infection, or inflammation. Interleukin (IL)-6 is a potent inducer of acute phase proteins that can include proteinase inhibitors, coagulation and complement proteins, and transport proteins. Clinically, only C-reactive protein (CRP) has been consistently used as a marker of injury response due to its dynamic reflection of inflammation. Importantly, CRP levels do not show diurnal variations and are not affected by feeding. Only pre-existing liver failure will impair CRP production. Therefore, it has become a useful biomarker of inflammation as well as response to treatment. Its accuracy surpasses that of the erythrocyte sedimentation rate.