Role of antibiotics in the management of chronic obstructive pulmonary disease.

Exacerbations of chronic obstructive pulmonary disease (COPD) are an important cause of morbidity and healthcare expenditure. In hospitalized patients, antibiotics decrease treatment failure and reduce mortality. There is also evidence for the effectiveness of antibiotics in treating COPD exacerbations in the community, but this is most convincing in patients with severe airflow obstruction and there is uncertainty regarding the value of antibiotics in patients with mild airflow obstruction. Treatment with antibiotics is usually recommended for patients who have an increase in sputum volume, sputum purulence and breathlessness, but the most important determinant of bacterial infection appears to be purulence. There is some evidence to suggest that the decision to use antibiotics can be guided by the use of procalcitonin, although this needs to be confirmed in further studies. Newer broad-spectrum antibiotics may be more effective than older antibiotics but, because of concerns regarding antibiotic resistance, it may be appropriate to reserve them for patients at highest risk of treatment failure. A number of studies suggest that antibiotic courses of 5 days in duration may be as effective as those for 7 days or more in patients with mild-to-moderate exacerbations of COPD. Guidelines do not recommend the use of prophylactic antibiotics in COPD but there is preliminary evidence to suggest that they may reduce the number of exacerbations. Until the full results of these studies are published, it will not be clear if they should be used.