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

Abstract

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.