Thorax 66:450-451 doi:10.1136/thx.2009.129940
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Pneumocystis jirovecii in pleural infection: a nucleic acid amplification study

  1. Robert J O Davies1
  1. 1Oxford Pleural Unit, Oxford Centre for Respiratory Medicine, Churchill Hospital, Oxford, UK
  2. 2Centre for Infectious Diseases and International Health, Windeyer Institute for Medical Sciences, University College London, London, UK
  3. 3North Bristol Lung Centre, Southmead Hospital, Bristol, UK
  4. 4Centre for Sexual Health and HIV Research, Department of Primary Care and Population Sciences, University College London, London, UK
  1. Correspondence to Dr John M Wrightson, Oxford Pleural Unit, Oxford Centre for Respiratory Medicine, Churchill Hospital, Oxford Radcliffe Hospitals NHS Trust, Headington, Oxford OX3 7LJ, UK; johnwrightson{at}
  • Accepted 14 January 2010
  • Published Online First 30 August 2010

Pleural infection is associated with 20% mortality in the 80 000 new cases per year in the UK and USA. Streptococcus species cause ∼50% of community-acquired bacterial pleural infection.1 Staphylococcus aureus and anaerobes are isolated in 8% and 20% of cases, respectively, and 12% of pleural infections yield polymicrobial cultures. However, even using culture and nucleic acid amplification techniques (NAATs), 26% of cases remain microbiologically obscure.

The negative microbiology may be due to previous antibiotic treatment, varying pathogen prevalence in different pleural fluid locules (already known to vary biochemically2) or the presence of organisms that are difficult to detect using conventional techniques. One such possible organism is Pneumocystis jirovecii, which requires specialist diagnostic techniques (eg, Grocott–Gomori methenamine silver staining or NAATs).

P jirovecii has been identified in sputum and bronchoalveolar lavage (BAL) fluid from both immunocompromised and immunocompetent individuals—it has been isolated from BAL fluid using NAATs …