Beyond Smoking Cessation, Bronchodilator, and Oxygen Therapy in COPD

Abstract

We appreciate the opportunity to respond to the comments by Aguilar and Navarro on our article. 1 By addressing their observations, we hope to clarify several points. First, we concur with their assertion regarding the potential for enteroviral shedding (rather than rhinoviral) and the limitations of the assay used. However, and more important, the patients studied all suffered from clinical syndromes consistent with pneumonia for which no other pathogen was identified. This fact and the temporal association between symptomatology and the positive test result strongly indicate that, in these subjects, most infections were, in reality, from rhinovirus. Second, a different polymerase chain reaction assay was used to identify cytomegalovirus (CMV; Qiagen, Rotogene). Furthermore, cases of CMV pneumonia were determined based only on specimens derived from bronchoalveolar lavage and after carful adjudication by one investigator. Moreover, if one removed the five cases of CMV pneumonia from our cohort, it would not substantially alter the conclusion about the prevalence of viral pathogens in pneumonia leading to acute respiratory failure. Third, no diagnostic methodology is perfect. All have limitations and must be interpreted based on the clinical scenario. For example, confounding from prior antibiotics might lead to the misclassification of some patients with concomitant bacterial and viral coinfection as "viral only." The central point is not perfect diagnostic accuracy, as Aguilar and Navarro seem to imply. If therapeutic decisions were only to be based on tests with perfect precision and accuracy, clinical medicine would grind to a halt. Rather, the key issue is antibiotic stewardship. By identifying a viral etiology in the appropriate clinical scenario in which no bacterial pathogen exists identifies a patient unlikely to benefit from antibiotic treatment. So the issue about the role of viruses in pneumonia and respiratory failure is not whether the "jury is still out." The debate has now clearly shifted to where the burden of proof lies.