Diffuse Bronchiectasis of Genetic or Idiopathic Origin

Bronchiectasis is a significant cause of morbidity and mortality. It is the end point of a pathological process. We should be aiming to identify at risk patients before they develop bronchiectasis and treat them aggressively to prevent disease progression. With improved social conditions and health care, infective causes of bronchiectasis have diminished in higher-income countries, and genetic causes are therefore relatively more common. The underlying cause of bronchiectasis should always be sought and readdressed, for example as discoveries of innate immune defects are made. ‘Idiopathic bronchiectasis’ should be a diagnosis of last resort. This chapter reviews potential genetic causes of bronchiectasis and suggests a plan for investigating the underlying aetiology. Management is discussed but it is important to note that suggested treatment strategies are often extrapolated from evidence in bronchiectasis associated with cystic fibrosis; this is likely to be inappropriate in diseases of differing pathophysiology. Rare lung diseases need to be moved out of the ‘orphan’ category by instigating multi-centre, multi-national clinical trials and producing disease-specific evidence-based guidelines.