[Acute infection of the lower respiratory tract: how long to observe?]

Acute infections of the lower respiratory tract first require a weighing up of risks, which is of importance in particular for the decision for or against antibiotic therapy. Severe or longlasting exacerbations of a chronic obstructive bronchitis, severe and rapidly progressive bronchial asthma or infection associated with bronchiectasis in an underlying antibody deficiency syndrome, primary ciliary dyskinesia and mucoviscidosis. In the case of systemic immunodeficiencies such as the antibody deficiency syndrome, HIV infection or immunosuppressive therapy, the indication for antibiotic treatment is more liberally established. In combination with respiratory tract infections, serious underlying disease such as left heart insufficiency or diseases of the lungs, may become life-threatening. Of decisive importance for the outcome in such cases are, besides the use of antibiotics, such as treatment of the cardiac insufficiency or long-term oxygen therapy. Timely vaccination can prevent severe illness.