Respiratory tract infections: when is antibiotic therapy indicated?

Antibiotic therapy of purulent bronchitis is a matter of continuing controversy. However, recent studies on the pathogenicity of airway hyperreactivity, granulocyte-mediated bronchial obstruction, and histamine production of Haemophilus influenzae indicate an important role for viral and bacterial infections in exacerbations of chronic obstructive lung disease (COLD). Considering the different stages of COLD in relation to lung function, bacterial pathogens, and relevant findings and symptoms of the individual patient, antibiotic treatment should be based on three different degrees of severity.