Of the 131 patients evaluated, 49 chest radiographs were reported abnormal, with the final diagnosis of primary lung pathology other than asthma made in 29 patients, including 8 patients with bronchiectasis, 8 patients with interstitial lung disease, and 2 patients with neoplasm. The authors did not report the sensitivity or specificity of chest radiography in the setting of chronic cough; however, abnormal radiography was positively associated with underlying primary pulmonary pathology other than asthma (odds ratio 7.7) [7]. Ojoo et al [17] prospectively evaluated 112 patients with chronic cough in a similar standardized clinical investigative protocol. In this study, 7 radiographs (6.3%) were reported contributory to the final diagnosis. Of the 92 patients with diagnosis found at discharge, 12 (13%) patients had pathologies including bronchiectasis, interstitial lung disease, self-limiting cough, and 2 cases of lung cancer. Both of these studies reported clinical efficacy with standardized protocols utilizing initial chest radiography, with diagnosis achieved in 93% in the Kastelik et al study [7] and 82% in the Ojoo et al study [17]. The most commonly reported etiologies were reflux, asthma, postinfective or viral cough, and rhinitis, representing between 61% to 67% of final diagnosis, which were more common than bronchiectasis, interstitial lung disease, and neoplasm, which represents <13% to 18% of final diagnosis [7,17]. Both case series are limited by sample size, and both studies were performed out of referral centers, likely contributing to selection bias. Retrospective analyses have been performed specific to chronic cough and normal chest radiography. Turner et al [16] retrospectively reviewed the medical records of 404 patients with chronic cough referred to specialty care who either had or subsequently were found to have a normal chest radiograph.
Chronic Cough. Of the 131 patients evaluated, 49 chest radiographs were reported abnormal, with the final diagnosis of primary lung pathology other than asthma made in 29 patients, including 8 patients with bronchiectasis, 8 patients with interstitial lung disease, and 2 patients with neoplasm. The authors did not report the sensitivity or specificity of chest radiography in the setting of chronic cough; however, abnormal radiography was positively associated with underlying primary pulmonary pathology other than asthma (odds ratio 7.7) [7]. Ojoo et al [17] prospectively evaluated 112 patients with chronic cough in a similar standardized clinical investigative protocol. In this study, 7 radiographs (6.3%) were reported contributory to the final diagnosis. Of the 92 patients with diagnosis found at discharge, 12 (13%) patients had pathologies including bronchiectasis, interstitial lung disease, self-limiting cough, and 2 cases of lung cancer. Both of these studies reported clinical efficacy with standardized protocols utilizing initial chest radiography, with diagnosis achieved in 93% in the Kastelik et al study [7] and 82% in the Ojoo et al study [17]. The most commonly reported etiologies were reflux, asthma, postinfective or viral cough, and rhinitis, representing between 61% to 67% of final diagnosis, which were more common than bronchiectasis, interstitial lung disease, and neoplasm, which represents <13% to 18% of final diagnosis [7,17]. Both case series are limited by sample size, and both studies were performed out of referral centers, likely contributing to selection bias. Retrospective analyses have been performed specific to chronic cough and normal chest radiography. Turner et al [16] retrospectively reviewed the medical records of 404 patients with chronic cough referred to specialty care who either had or subsequently were found to have a normal chest radiograph.