Pneumonia is a term which describes inflammation of the lung parenchyma characterised by exudation and consolidation into the alveoli.
There are various ways of categorising the pneumonias:
- by who gets them and when
- by the causative organism
- by the geography of acquisition
Overall (in the UK), Streptococcus pneumoniae is by far the most common agent.
Every year between 0.5% and 1% of adults in the UK will have community-acquired pneumonia
- diagnosed in 5-12% of adults who present to GPs with symptoms of lower respiratory tract infection, and 22-42% of these are admitted to hospital, where the mortality rate is between 5% and 14%
- between 1.2% and 10% of adults admitted to hospital with community-acquired pneumonia are managed in an intensive care unit, and for these patients the risk of dying is more than 30%
- more than half of pneumonia-related deaths occur in people older than 84 years