Serum C-reactive protein and complement proteins in patients with acute myocardial infarction.

C-reactive protein (CRP) and complement proteins levels were determined in 20 patients with acute myocardial infarction (AMI) and 20 controls. Blood was obtained from all subjects at admission, 6 hr and 12 hr later. Serum CRP levels were determined by ELISA and complement proteins by radial immunodiffusion. A statistically significant elevation of the mean CRP level was obtained at 12 hr postadmission. The mean complement proteins levels were 16-49% higher in AMI patients than the controls. It appeared that the alternate pathway was activated initially, followed by activation of the classical pathway. The increased levels of CRP and complement proteins are suggestive of their involvement in AMI.