[Value of the assay of C-reactive protein in osteoarticular infection]

The C-reactive protein is specifically increased in the acute phase of inflammation. Its level in the serum is measured by the use of immunonephelometry and is obtainable after 2.5 hours. It normally ranges between 3 and 22 mg/litre. The authors have measured the C-reactive protein after 50 surgical procedures in septic cases. They have compared its levels with other biological tests such as the sedimentation rate and the leucocyte count. The variations in C-reactive protein occurred very early and were very extensive, the increase ranging between 200 and 1500 per cent after the surgical procedure. In cases without septic complications the level returned to normal within seven days, while the sedimentation rate only became normal after three months. In cases with septic complications, the rise of C-reactive protein appeared before clinical signs. Therefore, such an increase should lead to a search for a persistent infective focus or the presence of an osteitis. However, this biological test cannot differentiate between an acute infective and a severe inflammatory process.