• Pneumonia

Peripneumony, peripleumoniacon and pleurisy were all terms used by the ancient Greeks and Romans to refer to illnesses which include the condition we now know as pneumonia. In the early 19th century, Laennec separated ‘pleurisy’ from pneumonia, and later that century, Rokitansky was probably the first to recognise bronchopneumonia and lobar pneumonia as separate pathological entitities. In 1938, Reimann1 introduced the term ‘atypical pneumonia’ for a group of pneumonias with a slower evolution and later link with mycoplasma aetiology (although subsequent studies suggest that such a clinical distinction is difficult and not useful in routine practice). The late 19th and 20th centuries were those of microbial discovery and the multiplicity of microbial pathogens that commonly cause pneumonia were recognised. It was only later in the 20th century, with alterations in the structure of society and healthcare facilities, that different patterns of microbial aetiology linked to social and population factors started to be detected, particularly in the USA. A high frequency of pneumonia associated with Gram-negative bacilli was found in a population with a high frequency of alcoholism.2 In a US study published in 1973, Gram-negative bacteria were found, perhaps for the first time, to be associated with pneumonia arising in those in institutional residence,3 and similar findings were found in patients with pneumonia developing in nursing homes—nursing home-acquired pneumonia (NHAP).4 This was the precursor to the current internationally recognised classification of pneumonia by site of origin into either hospital acquired pneumonia (HAP) or community acquired pneumonia (CAP)—a classification that is easy to apply at patient presentation, and which links to a different spectrum …