RT Journal Article SR Electronic T1 Pneumomediastinum: a rare manifestation of hypersensitivity pneumonitis in a patient presenting with unexplained breathlessness at the Borders General Hospital JF BMJ Case Reports FD BMJ Publishing Group Ltd SP bcr2015211593 DO 10.1136/bcr-2015-211593 VO 2015 A1 Robert Grecian A1 Jakki Faccenda A1 Luis Ferrando YR 2015 UL http://casereports.bmj.com/content/2015/bcr-2015-211593.abstract AB A 48-year-old woman from the Scottish Borders presented to her general practitioner with exertional dyspnoea. There was a delay in diagnosis of the underlying respiratory condition, due to initial investigations being suggestive of cardiac disease. Subsequently, the patient developed clinical symptoms and signs of pneumomediastinum, which was discovered on radiological imaging. Detailed history-taking and further clinical testing confirmed the cause of this to be hypersensitivity pneumonitis due to sensitisation to pet birds. The patient was treated with high dose steroids and went on to make a good recovery. The birds were rehomed.