C-reactive protein velocity following antibiotics in patients with chronic obstructive pulmonary disease exacerbation and community acquired pneumonia.

INTRODUCTION: Distinguishing community acquired pneumonia (CAP) from chronic obstructive pulmonary disease (COPD) exacerbation is a challenging task, since fever, productive cough, dyspnea, and leukocytosis are all common features of both conditions. Moreover, chest X-ray might not be sensitive enough. It is therefore quite common for physicians to prescribe unnecessary antibiotics for COPD exacerbation, leading to resistant bacteria and other related adverse affects.

AIM: To study whether CRP levels upon admission and the delta in CRP levels following initiation of antibacterial treatment, could provide an efficient tool for distinguishing CAP from COPD exacerbation.

METHODS: The study group included 36 COPD exacerbation and 49 CAP patients, admitted to a single Internal Medicine department during the years 2004-2006. All patients were treated with cephalosporins and macrolides upon admission.

RESULTS: CRP levels upon admission were significantly higher among CAP patients than among COPD exacerbation patients (111.5+/-104.4 vs. 34.9+/-28.6 mg/l, p<0.0001). CRP levels on the second day of hospitalization, following antibiotic administration to all patients, made a sharp incline in 36.7% of CAP patients compared to only 5.9% of COPD exacerbation patients (p=0.005), and remained unchanged in 61.8% of COPD patients compared to 16.3% of CAP patients (p=0.0006).

CONCLUSIONS: CRP levels upon admission and the delta in CRP levels following initiation of antibacterial treatment could provide an efficient tool for distinguishing CAP from COPD exacerbation.