Abstract
Background. Current guidelines recommend empiric antibiotic therapy for all patients who require hospitalization for community-acquired pneumonia (CAP). In such patients, we sought to determine whether clinical, imaging or laboratory features sufficiently enabled exclusion of bacterial coinfection so that antibiotics could be withheld from patients who test positive for a respiratory virus.
Methods. In patients hospitalized for CAP, we selected for study those who provided a high-quality sputum sample at or shortly after admission and who were tested for a respiratory virus. We performed quantitative bacteriologic studies on sputum to determine the presence of bacterial coinfection and reviewed all clinical, radiologic and laboratory studies.
Results. 122 patients were studied. 77 (63.1%) had bacterial infection, 16 (13.1%) viral infection, and 29 (23.8%) bacterial/viral coinfection. No clinical, laboratory or imaging findings allowed exclusion of bacterial coinfection in patients who tested positive for a respiratory virus. A significantly greater proportion of patients with bacterial/viral coinfection (30%) were admitted or transferred to the ICU during their hospital course, compared to 17% and 19% of patients with bacterial or viral infection, respectively
Conclusions. Even if a test for a respiratory virus test is positive in a patient hospitalized for CAP, no sufficiently differentiating features exclude bacterial coinfection, thereby supporting the recommendation that antibiotics be administered empirically at admission.