C-REACTIVE PROTEIN - A CLINICAL MARKER IN COMMUNITY-ACQUIRED PNEUMONIA

Study objective: To assess the range of plasma C-reactive protein (CRP ) in patients presenting with community-acquired pneumonia and to comp are the serial changes of this acute-phase protein with clinical outco me. Design: Prospective hospital-based study, including separate retro spective case series. Patients: Twenty-eight consecutive patients (mea n age, 60 years) admitted to our hospital with community-acquired pneu monia were studied. Serial daily plasma samples were taken and assayed for CRP, tumor necrosis factor-alpha (TNF-alpha), and interleukin 6 ( IL-6), Clinical parameters, laboratory data, and response to treatment were recorded. Four other patients considered to be antibiotic failur es (three empyemas, one death) were studied separately. Results: Two p atients died. Of those who survived, mean (+/-SD) CRP values for days 1, 2, 3, 4, and 5 were as follows: 136+/-43, 96+/-44, 53+/-36, 54+/-43 , and 44+/-31 mg/L. CRP levels on day 1 in patients who had received a ntibiotics prior to hospital admission were significantly lower than t hose who had not, 107+/-42 and 152+/-44 mg/L (p<0.05). CRP levels did not correlate with other laboratory parameters or with recognized pred ictors of mortality, A CRP value that continued to rise despite antibi otic treatment was associated with infective complications or death, O nly 52% of patients had detectable TNF-alpha and 24% detectable IL-6 a t some point during their hospital stay. Conclusions: CRP is a sensiti ve marker of pneumonia, A persistently high or rising CRP level sugges ts antibiotic treatment failure or the development of an infective com plication, These results suggest that CRP, rather than TNF-alpha or IL -6, may have a role as a clinical marker in pneumonia.