Pulmonary characteristics of inflammatory bowel disease

Background: Pulmonary manifestations of inflammatory bowel disease (IBD) have been considered a rare extraintestinal manifestation, however recent evidence suggests otherwise. Previous work has focused on individual aspects of pulmonary manifestations between Crohn's disease (CD) and ulcerative colitis (UC). As such, we compared patients with CD and UC with respect to symptoms, imaging findings, lung function, treatments, and outcomes. Methods: A single-center, retrospective, observational study was conducted that included patients aged 18 years and older with a confirmed diagnosis of either UC or CD, who had either a Chest Computed Tomography (CT) and/or Pulmonary Function Tests (PFTs) performed between 2014 and 2019. Data was collected from chart review. Comparisons were made between UC and CD groups. Results: 319 patients, with 221 diagnosed with CD and 98 with UC were included. Patients with UC exhibited a higher prevalence of coronary artery disease (p < 0.05) and a concomitant autoimmune disease (p < 0.05). 21/319 (6.6 %) patients exhibited IBD-related pulmonary disease. No differences in symptoms between patients with UC and CD were found. Common CT findings included ground glass opacities/consolidations (43.2 %), nodules (39.2 %), and emphysema (14.7 %), however these were not different between groups. The most common lung function abnormality was a presumed mixed ventilatory defect. In our cohort, patients with ulcerative colitis had a higher all cause mortality. Conclusion: Pulmonary abnormalities in patients with IBD are common and carry significant morbidity and mortality. We found no notable differences in clinical, physiologic, or radiographic manifestations between UC and CD patients despite differences in pathophysiology.