Management of pneumonia in the outpatient setting.

Most patients with pneumonia never reach the hospital but are managed in the community. Unlike patients admitted to the hospital, in most, no investigations are performed and the diagnosis is based on clinical features. Less than half of those with clinical pneumonia have radiographic infiltrates and some of those with lower respiratory tract infection that is not considered to be pneumonia do. Few studies have investigated this condition, partly because of these diagnostic difficulties. The importance of distinction of these conditions is uncertain at present. The role of microbiological investigations in patients with pneumonia in the community requires clarification. For most patients it is unlikely that such tests will alter management, but it is not possible to predict those in whom such tests may help. What little is known about the microbial cause of pneumonia managed outside of the hospital is that the causative pathogens are similar to those found in studies of hospitalized patients, with the exception of pathogens usually associated with severe illness such as legionella and staphylococci, which are uncommon. Empirical antibiotic therapy can be predicted from the above findings, but much further research is required to fill in current gaps in our knowledge.