There is no universally-accepted definition of an acute COPD exacerbation. They involve a sudden deterioration of symptoms, including increased breathlessness as well as increased quantity and (often) changes to the colour of phlegm. Exacerbations are a major cause of morbidity and mortality in COPD patients.

Exacerbations are commonly (probably 75%) associated with infections which may be viral, bacterial or both. Pseudomonas aeruginosa is commonly found in COPD exacerbations, but is by no means the only bacterium associated with these declines in lung function. Furthermore, it is becoming clear that stable patients have multiple bacterial colonisations as well. Our understanding of the processes leading to exacerbations is still not concrete and prophylaxis/management of this problem is still evolving.

Exacerbations may also be related to poor compliance with prescribed medications, or poor use of inhalers. COPD patients are encouraged to self-manage exacerbations by having antibiotics at home, and/or by increasing the use of their bronchodilator therapies. Self-management with corticosteroids is also helpful in some cases.

There’s an in-depth review of infections in COPD and their contributions to exacerbations here.

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