Pneumonia

Pneumonia is a common lung infection that causes significant mortality and morbidity worldwide, particularly in children and elderly people. The microbiological aetiology varies by location, with a variety of viruses and bacteria causing disease. Bacterial causes are usually acquired by microaspiration of organisms colonizing the nasopharynx. Microbes reaching the distal airways and alveoli induce a local and sometimes systemic inflammatory response, as well as occasionally disseminating distal to the lung.