Lower Respiratory Tract Infections

Abstract

The main acute infections of the lower respiratory tract — pneumonia and acute bronchitis — are usually both acquired and treated outside hospital. Admission to hospital occurs when the infection is severe or the patient is otherwise unwell. The same general principles of diagnosis and treatment apply whether the patient is managed in hospital or outside. Attempts to identify the causative organism are rarely made outside hospital and even in hospital positive identification is usually not possible in the first 48 h. Antibiotics are the only specific treatment, and if these are to be effective they should be started promptly as soon as the infection is diagnosed. The choice of antibiotic is determined by clinical diagnosis of the underlying infection and a judgement of the most likely organism responsible. The patient should therefore be assessed: (a) to determine clinically whether a lower respiratory tract infection is present; (b) to determine the type of infection, whether pneumonia or acute bronchitis; and (c) to decide, on the basis of the information available, which organism is likely to be causing the infection and which antibiotic or antibiotics are likely to be effective.