Field Epidemiology Manual Wiki


Last modified at 4/25/2016 3:53 PM by Vladimir Prikazsky

The “Point prevalence survey of healthcare associated infections and antimicrobial use in European acute care hospitals” protocol adopts the following definition of Pneumonia (PN).

definition of pneumonia (PN) is based on three types of criteria: radiological, clinical and microbiological.


two or more serial chest x-rays or CT-scans with a suggestive image of pneumonia for patients with underlying cardiac or pulmonary disease, and at least one of the following (in patients without underlying cardiac or pulmonary disease one definitive chest x-ray or CT-scan is sufficient).


  • fever> 38 °C with no other cause;
  • leukopenia (<4000 WBC/mm3) or leucocytosis (≥ 12 000 WBC/mm3);

 and at least one of the following (or at least two if clinical pneumonia only = PN 4 and PN 5):

  • new onset of purulent sputum, or change in character of sputum (colour, odour, quantity, consistency);
  • cough or dyspnoea or tachypnoea;
  • suggestive auscultation (rales or bronchial breath sounds), rhonchi, wheezing;
  • worsening gas exchange (e.g. O2 desaturation or increased oxygen requirements or increased ventilation demand);

and (microbiological):

according to the used diagnostic method:

a)      bacteriologic diagnostic test performed by:

  • positive quantitative culture from minimally contaminated LRT (lower respiratory tract) specimen (PN 1):
    • bronco-alveolar lavage (BAL) with a threshold of > 104 CFU*/ml or ≥ 5 % of BAL obtained cells contain intracellular bacteria on direct microscopic exam (classified on the diagnostic category BAL);
    • protected brush (PB Wimberley) with a threshold of > 103 CFU/ml;
    • distal protected aspirate (DPA) with a threshold of > 103 CFU/ml;
  • positive quantitative culture from possibly contaminated LRT specimen (PN 2):
    • quantitative culture of LRT specimen (e.g. endotracheal aspirate) with a threshold of 106 CFU/ml

b)      Alternative microbiology methods (PN 3):

  • positive blood culture not related to another source of infection;
  • positive growth in culture of pleural fluid;
  • pleural or pulmonary abscess with positive needle aspiration;
  • histologic pulmonary exam shows evidence of pneumonia;
  • positive exams for pneumonia with virus or particular germs (Legionella spp., Aspergillusspp., mycobacteria, mycoplasma, Pneumocystis carinii):
    • positive detection of viral antigen or antibody from respiratory secretions (e.g. EIA, FAMA, shell vial assay, PCR);
    • positive direct exam or positive culture from bronchial secretions or tissue;
    • seroconversion (e.g. influenza viruses, Legionella spp., Chlamydiaspp.);
    • detection of antigens in urine (Legionella spp.).

c)       Others:

  • positive sputum culture or non-quantitative LRT specimen culture (PN 4);
  • no positive microbiology (PN 5).


PN 1 and PN 2 criteria were validated without previous antimicrobial therapy.



Link to European IC/HH Core Competencies

Area 3. Surveillance and investigation of healthcare associated infection (HAI)