Risk factors for post-bronchoscopy pneumonia: a case–control study

The bronchoscopy, though usually safe, is occasionally associated with complications, such as pneumonia. However, the use of prophylactic antibiotics is not recommended by the guidelines of the British Thoracic Society. Thus far there are few reports of the risk factors for post-bronchoscopy pneumonia; the purpose of this study was to evaluate these risk factors. We retrospectively collected data on patients in whom post-bronchoscopy pneumonia developed from the medical records of 2,265 patients who received 2666 diagnostic bronchoscopies at our institution between April 2006 and November 2011. Twice as many patients were enrolled in the control group as in the pneumonia group. The patients were matched for age and sex. In total, 37 patients (1.4%) had post-bronchoscopy pneumonia. Univariate analysis showed that a significantly larger proportion of patients in the pneumonia group had tracheobronchial stenosis (75.7% vs 18.9%, p < 0.01) and a final diagnosis of primary lung cancer (75.7% vs 43.2%, p < 0.01) than in the control group. The pneumonia group tended to have more patients with a history of smoking (83.8% vs 67.1%, p = 0.06) or bronchoalveolar lavage (BAL) (4.3% vs 14.9%, p = 0.14) than the control group. In multivariate analysis, we found that tracheobronchial stenosis remained an independent risk factor for post-bronchoscopy pneumonia (odds ratio: 7.8, 95%CI: 2.5–24.2). In conclusion, tracheobronchial stenosis was identified as an independent risk factor for post-bronchoscopy pneumonia by multivariate analysis in this age- and sex- matched case control study.