Cough and bronchiectasis.

Bronchiectasis is a chronic lung disease with permanent airway dilatation, mucus retention and recurrent lower respiratory tract infections. Bronchiectasis is increasing in prevalence and has a significant morbidity and an excess mortality rate over age matched controls. It is increasingly identified during investigations into chronic cough and is evident high resolution CT scanning. There remain significant knowledge gaps in our understanding of the epidemiology, pathophysiology, prognosis and optimal treatments in bronchiectasis. This article reviews current concepts in bronchiectasis and focusses on the complex aspects of chronic cough in this setting. Cough is important in bronchiectasis as it is one of the most common presenting symptoms, it affects a patients' quality of life and in conjunction with cough hypersensitivity and airway hyper responsiveness may limit the successful uptake of treatment modalities such as inhaled antibiotics and/or inhaled mucoactive therapies. Effective coughing often assisted by physiotherapy is a cornerstone of bronchial toileting in bronchiectasis. Some patients however have ongoing non-productive cough symptoms suggesting a cough sensitisation syndrome. Post nasal drip and gastro-oesophageal reflux may complicate bronchiectasis and further lead to intractable cough syndromes. There may be multiple cough syndromes within an individual at interplay and careful assessment and multidisciplinary working is needed to optimize symptom control. This article also highlights the many unknowns in chronic cough in bronchiectasis.