Vocal cord dysfunction is a curious condition where the vocal cords go into paradoxical spasm whilst breathing (especially breathing in). This can mimic asthma with sudden onset intermittent breathlessness, wheeze and exercise related symptoms mainly in the throat with noisy breathing. Patients who fail to respond to conventional asthma treatment should have this diagnosis considered. The confirmatory tests include a “flattened” inspiratory lung function flow loop test and directly visualising the vocal cords during an episode. Symptoms are often intermittent and so difficult to diagnose and may respond to speech therapy and Botox injected into one vocal cord to reduce spasm.
Ref: Vocal cord dysfunction: asking the right questions. Bardin PG et al Clinical and Experimental Allergy 2015 45;1374-1375