Community-acquired pneumonia

Community-acquired pneumonia (CAP) is a common inflammatory process contained within the lungs in response to infection with non-hospital pathogens. Full resolution usually occurs with appropriate antimicrobial therapy. A significant proportion of patients develop severe CAP where there is failure to contain the local immune response. These patients can develop septic shock requiring admission to the intensive care unit. The CURB65 severity score is a rapid, objective way of predicting mortality and can be used to guide site of care decisions in conjunction with clinical assessment. Microbiological investigation of severe CAP permits pathogen-specific antibiotic therapy and provides epidemiological data. Complications include parapneumonic effusions and empyema. Outcome from severe CAP can be improved by prompt antibiotic therapy.