Description

Community acquired pneumonia (CAP) is a common cause of morbidity and mortality. Around 5% of all adults with acute lower respiratory tract infection treated in the community have clinical evidence of pneumonia and approximately 1 in 4 are admitted to hospital. In the UK Streptococcus pneumoniae is the most common cause of CAP occurring in 40% admitted to hospital. Whilst S. pneumoniae remains the most common cause of CAP, in patients admitted to ICU Legionella and Staphylococcus aureus also become more frequent. Chlamydia pneumoniae has been found to cause around 10% of cases of CAP, although it is often found in addition to another pathogen. This paper emphasises the importance of severity assessment as a cornerstone in determining which patients can be managed in the community and which require hospital or ICU admission; and in determining appropriate investigations. Antibiotic management is largely empirical and particularly directed against S. pneumoniae. We discuss the role of new quinolone antibiotics with enhanced activity against S. pneumoniae. Whilst the use of fluoroquinolones has been encouraging in clinical studies in CAP, clinical experience is at present relatively limited. Penicillin resistance occurs in around 5% of S.pneumoniae isolates in the UK and is frequently linked with macrolide resistance. In patients admitted to hospital a combination of a beta lactam and a macrolide is recommended for non-severe pneumonia. However the choice of antibiotic should be closely linked to local antibiotic resistance patterns.