Absence of Atypical Pathogens in Pleural Infection.

METHODS Patients Pleural fluids from 374 patients meeting standard criteria for pleural infection were analysed. Patients were recruited in 52 UK centres between 1999 and 2008 (including mycoplasma peak periods), as part of previous randomized trials of intrapleural therapy in pleural infection. Inclusion criteria were clinical evidence of infection and pleural fluid that was macroscopically purulent, positive on culture for bacterial infection, or positive for bacteria on Gram’s staining, or pleural fluid that had a pH of less than 7.2 (measured using a blood-gas analyser). Evidence of infection, which was assessed by the recruiting physician, included the presence of fever and elevated serum levels of inflammatory markers such as Creactive protein or an elevated white-cell count. Pleural fluid was stored at -80°C prior to analysis.